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Weather History

July 18 to July 24: This week in Denver weather history

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This Week in Denver Weather History

This week in weather history we really begin to see the arrival of monsoon season and the heavy rains and flooding it can bring to the Thornton and Denver area.  Be sure to check out the events on the 23rd and what the heavy rain brought to the Thornton area in 2004.

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In 2012…it was the hottest July on record in Denver since weather records began in 1872. The average temperature for the month was 78.9 degrees which was 4.7 degrees above normal. There were 27 days in which the high temperature equaled or exceeded 90 degrees…which established a new record. There were also 7 days in which the temperature equaled or exceeded 100 degrees which tied the record set in 2005.

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In 1934…a streak of 15 consecutive days of 90 degrees ranked 5th on the list of hot streaks.  The record of 24 consecutive days was established in the summer of 2008.

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In 2008…a streak of 26 consecutive days of 90 degrees shattered the previous record of 18 consecutive days established in 1901 and 1874.   Ironically…no new single day record high temperatures were set in the month of July. In august however…a record of 104 degrees was set on the 1st…and another record of 103 degrees was set on the 2nd. In addition…a record low min of 70 degrees was set on august 2nd.

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In 1997…an extended hot spell resulted in 3 temperature records being set. The maximum temperature reached 98 degrees on each of the days…setting records on the 16th and 18th. The low temperature of 71 degrees on the 17th was a record high minimum for the date. The high temperature reached 100 degrees on the 17th at the site of the former Stapleton International Airport.

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In 1874…the temperature climbed to 90 degrees or more for the 18th consecutive day…setting a record. The record was equaled from July 6th through the 23rd in 1901.

In 1902…a thunderstorm produced northwest winds sustained to 45 mph with gusts to 48 mph along with rain and hail. Total precipitation was 0.53 inch.

In 1911…a shower produced north winds sustained to 44 mph.

In 1958…1 1/2 inch diameter hail fell 9 miles west-southwest of Stapleton Airport.

In 1981…a thunderstorm bombed Evergreen with about 2 inches of rain in 45 minutes. A heavy hailstorm left 5 to 7 inches of hail on the ground in some places and stopped the Colorado Open Golf Tournament at Hiwan.

In 1985…over 2 inches of rain doused the southwest suburbs of Denver. Street flooding occurred in the Montbello area of northeast Denver.

In 1992…nickel size hail fell across central Douglas County near Castle Rock and Sedalia. One inch diameter hail fell in Castle Rock.

In 1993…thunderstorm winds gusted to 60 mph at Strasburg east of Denver.

In 2004…heavy thunderstorm rainfall caused flooding over parts of the Virginia Canyon Road near Idaho Springs. Several sections of the roadway were washed out. The road was closed temporarily for repairs.

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In 2003…heavy rain producing thunderstorms caused flash flooding across southern metro Denver.  Automated rain gages measured 2 to 3 inches of rain in less than an hour.  The heavy rainfall caused many intersections and underpasses to flood…stranding motorists.  Sections of I-25 and I-225 were closed due to the high water.

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In 1987…a streak of 16 consecutive days of 90 degrees ranked 4th on the list of hot streaks.  The record of 24 consecutive days was established in the summer of 2008.

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In 1875…recent heavy rains produced high waters on many creeks and rivers in the area…which threatened the destruction of property at some locations.  Cherry Creek in the city was running the highest in 10 years.  Heavy rain in the mining regions over the last 2 days resulted in water running “everywhere” and the suspension of some work.

In 1881…a thunderstorm passing across the city produced lightning with no rain.  A woman was seriously injured when struck by lightning several blocks from the weather office in downtown Denver.

In 1934…the temperature reached a high of 100 degrees in downtown Denver.

In 1965…hail…rain…and lightning hit west metro Denver. Hail stones as large as 1 1/2 inches in diameter accumulated to a depth of 2 inches in Evergreen where 2.95 inches of rain in 2 hours caused some flooding in the business section of the town.  Lightning caused some power outages.

In 1973…two funnel clouds were observed 5 miles southeast of Littleton.  The same funnel clouds were observed for 20 minutes…5 miles west and 5 miles west-southwest of Arapahoe County airport…now Centennial Airport.

In 1975…lightning injured a man in Denver and caused power outages in Aurora…Lakewood…Westminster…and west Denver.

In 1984…strong thunderstorm winds gusting to 45 mph shattered 7 large plate glass windows at Stapleton International Airport.

In 1985…a tornado touched down in the surrey ridge area of northern Douglas County…just west of I-25.  Ten homes were damaged; one under construction was nearly destroyed.  Two vehicles were thrown off I-25 injuring three people.  A pick-up truck was thrown 50 feet by the twister.  In addition…a cluster of severe thunderstorms pounded all of metro Denver with torrential rain…hail…and wind.  The heaviest rain fell in Aurora where one location reported 2.37 inches in just 40 minutes.  One location in northeast Aurora received a total of 4.30 inches from the storm. There was extensive street and basement flooding…and a number of roads were damaged or washed out.  An Aurora boy suffered minor injuries when he was washed into a drainage ditch.  Golf ball size hail in Aurora piled up to 5 inches deep.  An inch of rain fell in 20 minutes at Stapleton International Airport…closing it to air traffic for an hour.  Up to 1 1/2 inches of rain fell in just 15 minutes over central Denver with the high water closing I-25.  The water was so deep on the freeway…that one vehicle was completely submerged and people were diving into the water from the freeway overpass.  Three homes in Littleton were damaged by lightning.  Wind blew out several windows from a high rise apartment building in southeast Denver. Rainfall totaled 1.51 inches at Stapleton International Airport.

In 1997…torrential rain and damaging hail pummeled eastern sections of metro Denver.  Hail up to 1.25 inches in diameter fell at the national weather service office on the site of the former Stapleton International Airport.  The hail continued for about 15 minutes and accumulated to a depth of 2 to 3 inches…causing extensive damage to cars in the area.  Heavy rainfall totaled 3.83 inches in about an hour from the nearly stationary thunderstorm.  Numerous cars stalled along I-70…and several homes were flooded in east Denver.  The roof of a building collapsed under the weight of the water.  The next day several “fatalities” were discovered near the national weather service office; two prairie dogs were found dead along with three rabbits that either drowned or were killed by the large hail.

In 1999…lightning struck two residences in Littleton…but caused only minor damage.  Lightning triggered a fire at a residence in cherry hills village.  A small portion of the roof and ceiling were damaged before the fire could be extinguished.

In 2000…hail as large as 1.25 inches in diameter fell near Roggen northeast of Denver.

In 2004…heavy rainfall caused flooding on the Virginia Canyon Road near Idaho Springs…which had to be closed for repairs.

In 2006…the temperature climbed to a high of 100 degrees.  The high temperature was not a record maximum for the date.

In 2007…a severe thunderstorm produced large hail…up to 1 inch in diameter…about 6 miles north of Northglenn.

In 2016…two men at the Indian Tree Golf Course in Arvada were struck by lightning when they sought shelter from a rapidly developing thunderstorm under a tree. One man died from his injuries while the other suffered minor injuries. Very heavy rainfall was observed across central and southern parts of Denver. The storm dropped around 1.5 inches of rainfall in 30 minutes and caused minor street flooding. Nickel size hail was reported west of Pine in central Jefferson County.

19-23

In 2005…the high temperature climbed above 100 degrees on each of the 5 days with readings of 101 on the 19th…105 on the 20th…104 on the 21st…and 102 on both the 22nd and 23rd. A new record maximum temperature for the month of July of 105 degrees was set on the 20th…which also equaled the all time record maximum for Denver of 105 degrees first set on august 8th in 1878.  Daily maximum temperature records were set on each day…and the 5 day period equaled the record for the most consecutive days of 100 degrees or more first set from July 4th through 8th in 1989.  The intense heat resulted in a high use of electricity for cooling purposes.  The demand for electric power exceeded the supply and rolling black-outs… Each lasting about an hour…were scheduled across metro Denver during the afternoons and early evenings.

Continue reading July 18 to July 24: This week in Denver weather history →

Weather History

July 11 to July 17: This week in Denver weather history

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This Week in Denver Weather History

As we move further into summer, we see a decrease in traditional things associated with severe weather like tornadoes.  However, there is a corresponding increase in heavy rain as Colorado gets closer to its monsoon season.  We see many occurences of dangerous flooding as well as damaging hail, deadly lightning and more as we look back at this week in Denver weather history.

1-18

In 1874…a streak of 18 consecutive days of 90 degrees tied for second with another streak that was later set in the summer of 1901. The record of 24 consecutive days was established in the summer of 2008.

1-31

In 2012…it was the hottest July on record in Denver since weather records began in 1872. The average temperature for the month was 78.9 degrees which was 4.7 degrees above normal. There were 27 days in which the high temperature equaled or exceeded 90 degrees…which established a new record. There were also 7 days in which the temperature equaled or exceeded 100 degrees which tied the record set in 2005.

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In 1901…a streak of 18 consecutive days of 90 degrees tied for second with another streak set in the summer of 1874. The record of 24 consecutive days was established in the summer of 2008.

7-25

In 1934…a streak of 15 consecutive days of 90 degrees ranked 5th on the list of hot streaks.  The record of 24 consecutive days was established in the summer of 2008.

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In 1872…heavy rainfall started at 4:00 pm and continued into the night.  The heavy rainfall damaged homes and buildings in all parts of the city.  Rainfall totaled 1.64 inches.

In 1888…the temperature reached 100 degrees in downtown Denver.

In 1954…the high temperature climbed to 102 degrees at Stapleton Airport.

In 1970…a girl walking in a park in southeast Denver received eye and facial injuries when lightning struck nearby.  Lightning also caused numerous power outages and heavy rainfall produced local flooding at several locations across metro Denver.

In 1974…large hail up to 1 1/2 inches in diameter fell in Thornton.

In 1990…the worst hailstorm in American history in terms of dollar damage at the time battered metro Denver.  Storm damage totaled 605 million dollars…as it cut a 5-to 10-mile wide swath from just southeast of Estes Park to northeast of Colorado springs.  Hail as large as baseballs (2.75 inches) pounded metro Denver.  Hardest hit areas were southeast Boulder County…the Jefferson County Airport in Broomfield… Arvada…east Wheat Ridge…southwest and south-central Westminster…west Thornton…northwest…west-central and downtown Denver…northeast and east-central Lakewood…just east of Littleton…portions of Arapahoe County west of I-25… And northern and central Douglas County near Castle Rock and franktown.  Golf ball to baseball size hail severely damaged roofs on thousands of homes and buildings…battered tens of thousands of automobiles…windows…signs…street lights…and traffic signals…stripped paint…awnings…and trim from buildings…punched holes in the roofs of two homes in Arvada…knocked out power and telephone service to thousands of homes and businesses…defoliated thousands of trees…ripped up greens and fairways on a number of golf courses…and severely damaged several aircraft tied down at Jefferson County Airport.  Hail the size of baseballs fell for several minutes in old town Arvada.  Later…golf ball size hail and heavy rain pummeled two northwest Denver amusement parks.  Hardest hit was Elitch Gardens amusement park where 47 people were injured and received treatment for bumps…cuts…and bruises at local hospitals.  Many of the injured were stranded on rides during the storm when power failed.  Hail clogged storm sewers…causing rain water to back up 3 to 6 feet deep on some roads and intersections in Arvada.  Several basements were flooded.  In some places hail was washed into drifts several feet deep.  In addition… The storm spawned 2 small tornadoes.  One touched down briefly in Lakewood near 6th avenue and Kipling Blvd….but did no damage.  In Castle Rock…a tornado (f1) did heavy damage to some homes and vehicles in the Founders Village development near Ridge Road.

In 2001…lightning struck two homes in Thornton.  Most of the damage was confined to the attics of both homes.  Hail as large as 3/4 inch in diameter fell in Keenesburg…Longmont… And near Boulder.

In 2015…a peak wind gust to 55 mph was measured from the northwest at Denver International Airport. A trace of rainfall was also observed.

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In 1872…heavy rain from 4:00 pm until 2:00 am caused much damage.  Rainfall totaled 1.76 inches.

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In 1881…during the early evening…a brisk rain fell for 30 minutes from a nearly clear sky containing not one tenth of clouds with the sun shining brightly.  Rainfall was 0.16 inch.

In 1885…thunderstorms produced widespread lightning across the city during the evening.  Several people were injured when their homes were struck by lightning.

In 1954…the high temperature reached 101 degrees at Stapleton Airport.

In 1962…lightning struck and killed a Denver man…while he was assisting a co-worker with his car.

In 1971…the temperature climbed to a high of 101 degrees at Stapleton International Airport.

In 1974…hail to 3/4 inch in diameter fell in Castle Rock.

In 1991…hail to 2 inches in diameter fell in Thornton with golf ball size hail in Brighton.  Dime size hail was recorded in the city of Denver.  Very heavy rain caused flooding across metro Denver.  Water was up to 2 feet deep in parts of Golden where one foot of water was reported in the lot of a mobile home park.  Flood water washed away part of a parking lot at the Colorado school of mines in Golden. Heavy rain caused a rock slide and flooding along I-70 in the foothills just west of Denver.  Flood waters were a foot deep at the intersection of I-70 and I-25 just north of downtown Denver.  A funnel cloud was sighted just east of the Rocky Mountain Arsenal.

In 1996…very heavy rainfall from a fast moving thunderstorm dumped 2 to 3 inches of rain within an hour over southern Jefferson County.  Two people were killed near the town of Buffalo Creek when a 20-foot wall of water flooded the area.  Utility poles and trees were uprooted; cars… Propane tanks…and bridges were destroyed in the flood’s path.  Entire buildings were moved from their foundations and heavily damaged by the floodwaters.  The first fatality occurred along State Highway 126 when the driver of a pick-up truck was washed off the road by the deadly wall of water.  The second death occurred farther upstream when a man in a 5th-wheel trailer was washed away.  This was the second disaster to strike the area in the last couple of months.  The community was already recovering from a wildfire which burned about 12 thousand acres of forest land in late May.  With the forest burned by fire…very little vegetation was available to slow the storm’s runoff…which resulted in the flash flood.  Power…water…and sewer service were heavily damaged in the flood and…in some cases…beyond repair.  The cost of repairing the roads and water system in the area was estimated at around a half million dollars.  Elsewhere across metro Denver…severe thunderstorms produced hail…damaging winds…and small tornadoes.  Weak tornadoes (f0) were reported in Broomfield… 3 miles east of Englewood…and in Dacono.  No damage was reported…except a trampoline was blown into a window and several trees were downed in Broomfield.  Thunderstorm wind gusts estimated as high as 60 mph blew a fence down in Louisville where winds also toppled a tree near a house. The house received only minor damage.  Large hail…strong winds and heavy rain caused substantial property damage in portions of southeastern Boulder and northern Jefferson counties.  Damage estimates in the Broomfield area alone were about 1 million dollars.  Winds gusted to 81 mph in Broomfield.  Large hail…3/4 to 1 1/2 inches in diameter fell in Evergreen…Lakewood…Englewood…Broomfield…near Morrison…northeast of Boulder…and just east of Denver International Airport.

In 2000…heavy rain fell across a portion of the Hi Meadow Fire burn area near Buffalo Creek…causing localized flooding.  About 3/4 inch of rain fell in 30 minutes over Miller Gulch.  Some culverts become plugged by debris from the fire.  As a result…small sections of a U.S. Forest Service road along Miller Creek were washed out.  Lightning struck a home in Castle Rock…causing extensive damage to the roof…attic…and second floor.

In 2011…severe thunderstorms developed over parts of Adams and Denver Counties. At Denver International Airport…a severe thunderstorm produced a peak wind gust to 66 mph… with another gust to 59 mph measured in Denver. In Commerce City…the intense winds blew down a large tree.

Continue reading July 11 to July 17: This week in Denver weather history →

Weather History

July 4 to July 10: This week in Denver weather history

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This Week in Denver Weather History

As we pointed out in our July weather preview, the month is not only our hottest but it is also the stormiest.  Scorching summer heat is certainly evident when we look back at this week in Denver weather history.  Perhaps more notable is the severe weather we have seen with everything from hail, damaging wind, dangerous lightning and deadly flooding having occurred.

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In 2000…the 29th marked the beginning of a near record hot streak for metro Denver.  The high temperatures…as recorded at Denver International Airport…exceeded the 90 degree mark for 17 consecutive days from June 29th through July 15th. The record of 24 consecutive 90 degree or above days was set from July 13th through August 5th…2008.

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In 1874…a streak of 18 consecutive days of 90 degrees tied for second with another streak that was later set in the summer of 1901. The record of 24 consecutive days was established in the summer of 2008.

1-31

In 2012…it was the hottest July on record in Denver since weather records began in 1872. The average temperature for the month was 78.9 degrees which was 4.7 degrees above normal. There were 27 days in which the high temperature equaled or exceeded 90 degrees…which established a new record. There were also 7 days in which the temperature equaled or exceeded 100 degrees which tied the record set in 2005.

4

In 1874…the temperature reached a high of 102 degrees in downtown Denver.  Large forest fires in the mountains from the west-northwest to the south filled the atmosphere over the city with dense smoke.

In 1885…a thunderstorm produced sustained winds to 44 mph with gusts to 60 mph.  A circus tent was tattered by the strong winds.

In 1900…a thunderstorm produced northwest winds sustained to 42 mph with gusts to 51 mph…but only 0.05 inch of rain.

In 1903…the all time lowest temperature ever recorded in July…42 degrees…occurred. The temperature also occurred on July 31…1873.

In 1910…thunderstorm winds were sustained to 42 mph from the southwest.

In 1922…thunderstorm winds were sustained to 37 mph with gusts to 48 mph.

In 1956…a thunderstorm wind gust to 54 mph was recorded at Stapleton Airport.

In 1964…several men were knocked down by a bolt of lightning while playing golf in south metro Denver.  They got up and ran for cover when one of them was struck by a second bolt. He suffered burns and shock.

In 1987…a weak tornado was observed for 6 minutes…7 miles northeast of Watkins.  Hail 3/4 to 1 1/4 inches in diameter fell in southeast Aurora.

In 1988…lightning struck a group of people at the Jefferson County fairgrounds.  A 42-year-old woman was seriously injured and was hospitalized for 3 days.  Four other people sustained minor injuries.

In 1993…strong northwest winds uprooted several trees across metro Denver.  Wind gusts to 64 mph were reported at Erie north of Denver.  A west wind gust to 43 mph was recorded at Stapleton International Airport.

In 1995…lightning struck and injured two people standing in a field in Arvada.

In 1998…heavy thunderstorm rain…up to 2.75 inches…and marble size hail combined to flood local roads and fields near Roggen.

In 2002…heavy thunderstorm rain in the Hayman Fire burn area caused flash flooding.  In Jefferson County…gulch road was washed out.  In Douglas County…high water washed out some forest access roads as well…generally to the east of a line extending from Signal Butte to Deckers.

In 2010…intense thunderstorms produced torrential rainfall…  in excess of 5 inches in one hour…and caused flash flooding  in the vicinity of Elizabeth.  Numerous county roads were  washed out.  The combination of heavy rain and hail made it  necessary to run snow plows through town.  Extensive  basement flooding was also reported.  Severe thunderstorms  produced large hail from Aurora south to Elizabeth and  Larkspur.  The hail size ranged from 1 to 2 inches in  diameter.  A wet microburst produced 1.84 inches of rainfall  at Denver International Airport.  A peak wind gust to 48 mph  was also observed from the northeast.

In 2017…a microburst produced a wind gust to 61 mph…about 13  miles east-northeast of Denver International Airport.

4-5

In 1875…nearly every railroad running into the city was damaged by heavy thunderstorm rains.  The heavy rains washed out wooden bridges over normally dry creeks. Some trains were entirely suspended.  In the city…heavy thunderstorm rain totaled 1.05 inches on the 4th…but only 0.28 inch on the 5th.

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In 1989…one of the most intense heat waves on record roasted metro Denver.  The temperature reached 100 degrees or more on 5 consecutive days.  The city had previously never recorded more than 2 straight 100-degree days since records began in 1872.  Water and electricity usage reached all time highs.  The heat wave created extremely dry weather conditions…which contributed to a major forest fire in Boulder canyon on July 9th.  The temperature reached 103 degrees on the 8th…and the mercury climbed to 101 degrees on both the 4th and 5th…and to 102 degrees on both the 6th and 7th.  The low temperature of 68 degrees on the 8th equaled the record high minimum for the date.

Continue reading July 4 to July 10: This week in Denver weather history →

Weather History

June 27 to July 3: This week in Denver weather history

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This Week in Denver Weather History

Closing out June and entering July our look back at this week in Denver weather history is marked by severe weather and scorching heat.  Damaging hail to dangerous lightning are two common occurrences as is record-setting heat waves.

From the National Weather Service:

21-3

In 2002…the maximum temperature in Denver equaled or exceeded 90 degrees for 13 consecutive days…equaling the 5th longest such streak on record.  The record of 18 consecutive days was set during the summer of 1901.

26-27

In 1965…wind gusts to 38 mph were recorded in downtown Boulder…causing widespread minor damage.  A microburst wind gust to 41 mph was recorded at Stapleton International Airport.

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In 1873…Pikes Peak was hidden from view by smoke from forest fires in the mountains to the southwest of the city.

In 1927…the temperature cooled to a low of only 72 degrees… The all-time record high minimum for the month.

In 1980…lightning injured 4 people on a baseball diamond in Broomfield.  The bolt seriously injured the pitcher while also striking (out) the batter…catcher and second baseman.

In 1987…a microburst wind gust to 53 mph was recorded at Stapleton International Airport.

In 1990…the temperature reached a high of 102 degrees… Setting a new record maximum for the date.

In 1993…thunderstorm winds gusted to 60 mph across parts of metro Denver.  A wind gust to 50 mph blew over a 30-foot canvas tent at an amusement park southeast of Denver. Fifteen people…mostly children…were injured.  Microburst wind gusts to 33 mph were recorded at Stapleton International Airport.

In 2002…heavy rain…up to 3/4 inch…fell across sections of the Hayman burn area near Cheeseman Reservoir.  Several forest service roads were washed out and many culverts were plugged by debris.

In 2004…heavy rain producing thunderstorms caused rock and mud slides across the overland fire burn area in Jamestown. An estimated 50 tons of sand…dirt…rock…and ash slid into town…filling a culvert under main street.  The slide covered 150 to 225 feet of Main Street.  The flood was produced by half an inch of rain in 30 minutes.  A deluge of very heavy rainfall from nearly stationary thunderstorms caused flooding and flash flooding problems over parts of Jefferson and Douglas counties.  An automated rain gage in Golden measured 3.60 inches of rainfall in one hour.  Numerous homes were flooded in Golden…including one that was 146 years old. The home was listed as a complete loss.  State Highway 93 had to be closed from the Pine Ridge subdivision to the Golden Gate Canyon Road.   At the height of the storm…about 4 feet of water covered State Highway 93 through Golden… Forcing its temporary closure.  Several intersections were also flooded and impassable.  Rock and mud slides were reported in Golden Gate Canyon State Park.  At the Deer Creek Golf Course at Colorado 470 and Kipling…the greens were completely inundated by floodwaters.  Some backyards near the golf course were partially washed out.  In Douglas County…water up to a foot deep covered the roadways in Roxborough State Park.  The Waterton Canyon Road also had to be closed due to high water.

In 2010…a severe thunderstorm produced hail up to 1 inch in diameter near Strasburg. Hail up to 3/4 inch in diameter was reported in Aurora and Buckley Air Field.

In 2014…a severe thunderstorm produced hail…up to 1 inch in diameter…near Ft. Lupton.

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In 1873…there was a great deal of smoke over the city from forest fires in the mountains.

In 1875…smoke from forest fires in the foothills south of Denver were visible from the city.

In 1913…an apparent dry microburst produced southwest winds sustained to 44 mph with gusts to 48 mph in the city.

In 1925…a thunderstorm produced north winds sustained to 38 mph with gusts to 44 mph.

In 1958…a microburst caused a brief wind gust to 58 mph at Stapleton Airport.

In 1964…lightning struck several homes in metro Denver… Sparking fires.  Some flooding occurred in the stockyards area…at west 45th Avenue and St. Paul Street…and along Harvard Gulch.

In 1997…strong microburst winds of unknown speed downed several trees…signs…and at least one light pole in the Fort Lupton area.  Two trees knocked over by the storm downed power lines causing scattered outages.

In 2002…a thunderstorm wind gust to 60 mph was recorded in Parker.

In 2005…severe thunderstorms produced wind gusts to 66 mph near Longmont and to 60 mph near Niwot.  No damage was reported.  A thunderstorm produced a wind gust to 55 mph at Denver International Airport during the afternoon.

In 2015…a lightning strike injured 15 hikers as they were descending 500 feet below the summit of Mt Bierstadt…in Clear Creek County…south of Georgetown. Eight adults were were transported from the trailhead…and three of those were taken to Denver-area hospitals. One was in serious condition…the other two had non-life threatening injuries. The strike also killed a dog. Severe thunderstorms produced hail up to 1 1/2 inches in diameter…7 miles southwest of Byers…and 1 1/4 inches in diameter…13 miles north of Elizabeth.

In 2016…severe thunderstorms produced hail…from quarter to ping ball size…over northwest…west and southwest parts of Denver. In addition hail up to quarter size was also reported just southeast of Denver International Airport. Officially only a trace of rainfall was measured at the airport…with a peak wind gust of 35 mph from the west.

29

In 1874…eight different fires in mountain forests were visible from the city.  All of the fires were extensive… And the volume of smoke from each was immense.  Three of these fires had been burning from the 18th with varied intensity.

In 1911…an apparent dry microburst produced sustained winds to 45 mph.

In 1960…a strong gust of wind blew a small foreign sedan off the highway near Brighton…injuring the driver.  East winds gusted to 40 mph at Stapleton Airport.

In 1961…thunderstorm winds estimated as high as 40 to 50 mph occurred over southeast Denver.  No significant damage was reported.

In 1962…heavy rain and small hail caused some flooding in southwest Denver.

In 1995…upslope cloudiness with rain and fog cooled temperatures to record levels.  Low temperature of 47 degrees equaled the record for the date.  High temperature of only 54 degrees set a new record low maximum for the date.  Rainfall totaled 0.90 inch at Denver International Airport and 0.41 inch at the site of the former Stapleton International Airport.

In 2003…a severe thunderstorm in Parker produced hail to 1 inch in diameter.

In 2011…two airmen from the Colorado National Guard suffered minor injuries when they were struck by lightning. They were hit while on duty at a flight line at Buckley Air Force Base. At Denver International Airport…a microburst produced a peak wind gust to 72 mph.

29-2

In 1990…almost a year to date after the record breaking heat in early July 1989…the third longest heat wave in Denver history started.  From June 29th through July 2nd the temperature reached 100 degrees or more on four consecutive days.  The highest reading of 102 degrees occurred on the 29th…30th…and 1st.  Combined with the 102 degree reading on June 27th this would have been the longest heat wave on record…but the temperature climbed to only 98 degrees on June 28th.

29-15

In 2000…the 29th marked the beginning of a near record hot streak for metro Denver.  The high temperatures…as recorded at Denver International Airport…exceeded the 90 degree mark for 17 consecutive days from June 29th through July 15th. This was one day short of equaling the all time record.  The record of 18 consecutive 90 degree or above days was first set from July 1st through July 18th…1874.  The record was equaled from July 6th through July 23rd…1901.

Continue reading June 27 to July 3: This week in Denver weather history →

Weather History

June 20 to June 26: This week in Denver weather history

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This Week in Denver Weather History

Late June weather is usually relatively calm but when it turns severe, it can do so in spades.  Hail, flooding rains, tornadoes and more are not unusual.  This week in Denver weather history we see plenty of each of those including a hail storm in 1993 that damaged dozens of planes at Denver International Airport.

19-21

In 1875…smoke from several large forest fires in the mountains was visible from the city on each of these days.

20

In 1888…northwest winds were sustained to 44 mph.

In 1956…a microburst caused a brief wind gust to 58 mph at Stapleton Airport.

In 1964…hail up to 1 inch in diameter was reported 1 mile north of Stapleton International Airport.  A 3 minute hail storm at both Stapleton International Airport and Lowry Field piled small hail to one half inch deep.

In 1967…a strong thunderstorm dumped 1.95 inches of rain in less than an hour at Stapleton International Airport and produced a wind gust to 54 mph.  The storm caused some flooding in east Denver and Aurora.  There was widespread flooding to streets…basements…and store buildings and automobiles.  Hail stones to 3/4 inch in diameter were measured at Buckley Field in Aurora.  A tornado touched down just south of Littleton…damaging a barn and killing several head of cattle.

In 1985…a wind gust to 61 mph was reported at Golden Gate Canyon in the foothills west of Denver.

In 1986…a man was killed by lightning at Highlands Ranch south of Denver.

In 1987…several tornadoes were sighted across metro Denver.  A tornado touched down briefly 5 miles west of Parker.  A tornado was sighted just north of Chatfield Reservoir.  A tornado just northwest of Watkins was on the ground for 15 minutes.  A tornado near Barr Lake was taped by a television news crew.  It had a double vortex and was on the ground for about 10 minutes.  In addition to the 4 tornadoes…severe thunderstorms dumped large hail across metro Denver.  One inch hail was reported in southeast Aurora; 3/4 inch hail fell at the Denver technology center…Buckley Field…and Franktown.

In 1992…several short-lived tornadoes occurred in the vicinity of Barr Lake.  No injuries or damages were reported.  A water spout was sighted over the southern end of Barr Lake.  Funnel clouds were also sighted on the grounds of the rocky mountain arsenal by national weather service observers at Stapleton International Airport.

In 1994…hail up to dime size covered I-25 south of Denver and near Sedalia.  Heavy rain caused local flooding on the interstate highway.

In 1996…strong thunderstorm winds downed several large tree limbs in Boulder on the University of Colorado campus.  A stop light in the city was also blown down.

In 1999…lightning sparked an oil tank fire near Brighton.

In 2001…large hail driven by strong thunderstorm winds raked Denver international and Front Range airports.  Wind gusting to 54 mph along with hail as large 2 inches in diameter punched at least 14 thousand holes and cracks in the flat roofs of several buildings at Denver International Airport. In addition…93 planes and hundreds of cars were damaged. About 100 flights had to be cancelled…stranding 1500 travelers.  The airport was completely shut down for about 20 minutes.  The storm also damaged a ground avoidance radar used to track planes on the ground to prevent collisions. Damage was estimated at 10 million dollars…not counting the damage to the 93 airliners.  The storm moved south and struck Watkins with hail as large as 2 1/2 inches in diameter and winds gusting to 60 mph.  A least 30 private planes at Front Range airport were destroyed.  The radome protecting the national weather service doppler radar…which was tracking the storm…also sustained damage.  The large hail…damaging winds…and heavy rain pummeled a mobile home park near Watkins.  In the park…52 mobile homes…14 recreational vehicles…3 homes…and a commercial building were damaged.  Siding was riddled with holes and windows were broken.  Vehicles sustained extensive damage and car windows were shattered.  A handful of people were treated for minor cuts and bruises.  The strong winds also flipped a tractor trailer along I-70 near Watkins.  The storm caused power outages…which affected about 1200 residents. Excluding the damage at Denver International Airport…damage estimates totaled 49 million dollars…making the storm the costliest in the last 3 years and the 10th costliest since 1984.  A small tornado touched down just east of Brighton… But did no damage.  Hail as large as 2 inches in diameter fell near Fort Lupton with 3/4 inch hail measured in Bennett.  Precipitation from the storm totaled only 0.23 inch at Denver International Airport.

In 2002…heavy rain fell near the Hayman Wildfire burn area. Flash flooding washed out a 40-foot section of the access road to Cheeseman Reservoir.  Some debris was washed against a gate…blocking the road.  Hail to 1 1/2 inches in diameter fell near central city with 3/4 inch hail near Blackhawk.

In 2003…hail as large as 1 inch in diameter fell near Bennett and Strasburg with 3/4 inch hail measured in Denver…Golden… At Centennial Airport…and near Parker.  Hail as large as 7/8 inch was reported in Arvada.

In 2004…a severe thunderstorm produced hail to 3/4 inch in diameter in and near Brighton.

In 2005…severe thunderstorms produced large hail near the palmer divide.  Hail to 1 inch in diameter was measured near Larkspur with 7/8 inch hail near Sedalia and 3/4 inch hail in Greenland.  An apparent thunderstorm outflow produced a wind gust to 59 mph at Denver International Airport during the evening hours.

In 2010…lightning struck a home in Centennial and sparked a fire which caused extensive damage.

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In 1897…high winds raked the city overnight.  Southeast winds were sustained to 60 mph with gusts as high as 72 mph on the 20th.  Southeast winds were sustained to 57 mph with gusts to 60 mph on the 21st.

In 2007…a brief hot spell produced two temperature records. The high temperature of 97 degrees was tied on the 20th. A new record high temperature of 99 degrees was established on the 21st.

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In 1927…north winds were sustained to 40 mph with gusts to 44 mph.

In 1984…lightning struck and killed two children standing near a tree in a backyard in Lakewood.  Strong thunderstorm downbursts caused a wind gust to 58 mph in Northglenn and knocked down two power poles near Brighton.

In 1988…lightning struck a home in Denver…causing about ten thousand dollars damage.  Lightning damaged 3 homes in Littleton…and also hit a house in greenwood village that had been struck by lightning 7 years previously.

In 1991…thunderstorms produced widespread hail across metro Denver.  Hail as large as 2 1/2 inches fell at several locations across southwest metro Denver.  One storm spotter reported hail 8 inches deep near the intersection of I-25 and c-470.  Heavy rain with the storms caused some street flooding.  In Commerce City…several cars were under water… And in Westminster a police officer reported water up to the doors of his car.  Damage to homes and automobiles totaled 55 million dollars.

In 1992…a tornado touched down briefly near Bennett. Another tornado was briefly on the ground near Strasburg.

In 1994…heavy thunderstorm rains caused flooding in metro Denver.  Several vehicles were stalled in the high water on I-25.  Lightning struck an underground natural gas line in Aurora…causing a fire.  Widespread power outages were also observed.

In 1996…three homes were struck by lightning in Parker. The lightning struck the garage of the first home…which started a small fire that burned some siding and spread into the attic.  A second home sustained damage to the attic when a small fire was started.  The third home received only minor damage.  Lightning also sparked two small grass fires in the area.  A man in Lakewood received minor injuries when he was struck by lightning while working on a ladder.  A funnel cloud was sighted in Castle Rock.  Strong thunderstorm winds downed a large tree near crossroads mall in Boulder.  A small tornado (f0) briefly touched down near Lafayette.  No damage was reported.

In 1997…one inch diameter hail was measured in Boulder.

In 2002…a thunderstorm wind gust to 62 mph was recorded at Denver International Airport.

In 2005…severe thunderstorms produced hail to 1 inch in diameter in Broomfield along with 3/4 inch hail near Arvada.

In 2006…a man riding a motorcycle was struck and killed by lightning on U.S. Highway 36 between church ranch blvd. And Sheridan Blvd. In Westminster.  After the biker was struck…he and his motorcycle crashed into the center concrete median of the highway.  The lightning bolt left a crater in the highway asphalt that measured 18 inches long…8 inches wide and 4 inches deep.

In 2010…a severe thunderstorm produced hail up to 1 1/2 inches in diameter near Morrison. In Lafayette and Louisville…hail up to one inch in diameter was observed.

In 2014…three small tornadoes touched down in eastern Adams County near Barr Lake…Bennett and Front Range Airport. The tornado near Barr Lake damaged some out buildings and a storage shed. Minor roof damage to houses in the immediate area was reported near 168th Ave and Haymont Rd near 168th Ave and Haymont Rd. It was rated an EF1. The others did no damage.

Continue reading June 20 to June 26: This week in Denver weather history →

Weather History

June 13 to June 19: This week in Denver weather history

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This Week in Denver Weather History

June typically is a very eventful weather month and looking back at this week in Denver weather history that is clearly seen.  Among the more noteworthy items are the 2002 Hayman Fire, a 1965 flood that damaged dozens of bridges in the Denver area and the infamous tornadoes in 1988 that struck near downtown Denver.

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In 2012…it was the hottest June in Denver since weather records began back in 1872. The average temperature for the month was 75.0 degrees which was 7.6 degrees above normal. There were a total of seventeen 90 degree days in the month of June. The highlight of record setting month was a stretch of five consecutive 100 degree days from the 22nd to the 26th. This was only the third time in Denver weather history in which this happened. Two of the high temperatures during the stretch peaked at 105 degrees… which set the all time record for the month of June and tied the all-time maximum temperature for Denver.

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In 1999…damage from several hailstorms in and near metro Denver totaled 35 million dollars.  About 17.5 million dollars was from automobile claims with another 17.5 million in homeowner claims.  The areas hardest hit by the storms included Castle Rock…Commerce City…Evergreen… And Golden.

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In 2000…two large wildfires developed in the Front Range foothills as careless campers and very dry conditions proved to be a dangerous combination.  Strong winds gusting in excess of 60 mph on the 13th fanned the flames… Spreading both wildfires out of control.  Winds gusted to 78 mph atop Niwot Ridge near the Continental Divide west of Boulder.  The hi meadows wildfire…about 35 miles southwest of Denver…consumed nearly 11 thousand acres and 80 structures…mostly high priced homes.  The bobcat wildfire…located about 12 miles southwest of Fort Collins… Consumed nearly 11 thousand acres and 22 structures.  Late on the 16th…a strong cold front moved south over the great plains into northeastern Colorado.  Low level upslope conditions developed in the wake of the front…producing 2 to 4 inches of snowfall overnight at elevations above 8 thousand feet.  Firefighters were able to contain both fires shortly thereafter.

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In 1956…a microburst caused a brief wind gust to 59 mph at Stapleton Airport.

In 1957…an unconfirmed tornado appeared to touch the ground in the vicinity of Franktown.  No damage was reported from the twister.

In 1968…a violent gust of wind…possibly associated with a thunderstorm…caused 75 hundred dollars damage in Boulder.

In 1973…hail…1/2 to 3/4 inch in diameter…fell over Lakewood.  Flash flooding occurred in west Denver from the same storm.

In 1974…a thunderstorm wind gust to 64 mph was recorded at Stapleton International Airport.

In 1977…hail the size of table tennis balls…1 1/2 inches in diameter…was reported in Boulder.

In 1981…large hail to golf ball size fell in Denver… Northglenn…and Brighton.  Hail as large as baseballs was reported in Federal Heights.

In 1984…one of the worst hailstorms ever experienced in metro Denver struck the northwestern suburbs of Arvada…Wheat Ridge…and Lakewood…but large hail also fell in Golden… Southeast Denver…and Aurora.  Homes and other buildings sustained around 200 million dollars in damage.  Thousands of cars were battered by giant hailstones…and total damage to vehicles was estimated at 150 million dollars.  In some areas…golf ball size hail fell continuously for 30 to 40 minutes.  Some places were pelted with a few stones as large as grapefruits!  Roofs on thousands of structures were severely damaged.  Uncounted car windshields were broken; two-thirds of Arvada’s police cars were rendered inoperable.  Torrential rains…with as much as 4.75 inches in Lakewood clogged drains and caused widespread damage from flooding.  In some places hail was washed into drifts several feet deep.  About 20 people were injured by the giant hailstones.  One couple was hospitalized.  A woman drowned when she was trapped under a trailer by high water. Only pea size hail fell at Stapleton International Airport.

In 1988…2 inch hail fell in Parker.  Soft hail 1 inch in diameter fell at the mouth of turkey creek canyon 5 miles southeast of Morrison.  Hail between 1 inch and 1 3/4 inches fell at both Bennett and Strasburg.  A tornado touched down briefly at Strasburg.  A brief funnel cloud was sighted by national weather service observers 15 miles southwest of Stapleton International Airport.

In 1991…a Boulder man was injured when struck by lightning while in a tent.  He received only minor burns.

In 1997…lightning struck a home in Denver.  The extent of the damage was unknown.  A home in Littleton was also struck.  The house caught fire…but the extent of the damage was not known.

In 1998…a strong mountain wave produced a brief period of high winds along the Front Range.  A small building atop squaw pass west of Denver was blown down.  Tree limbs were downed across metro Denver.  Peak wind gusts included:  80 mph on squaw pass…69 mph at Jefferson County Airport near Broomfield…and 60 mph in Westminster and at the National Center for Atmospheric Research in Boulder.  West-northwest winds gusted to 51 mph at Denver International Airport.

In 2001…high winds developed briefly in Boulder County. A peak wind gust to 76 mph was recorded at the National Center for Atmospheric Research atop the mesa in Boulder. A wind gust to 72 mph was recorded at southern hills middle school in Boulder.  Lightning started a small fire…which damaged the roof of a house in Greenwood Village.

In 2009…severe thunderstorms produced hail up to one inch in diameter near Arvada and byers…as well as 7 miles north-northwest of Front Range airport near watkins.

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In 2006…the high temperature of 99 degrees on the 13th equaled the record maximum temperature for the date first set in 1994.  The high temperature of 102 degrees on the 14th was a new record maximum temperature for the date.

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In 1877…an evening thunderstorm produced lightning which struck several houses and killed a cow in the bottom land of the South Platte River

In 1886…hail as large as 3/4 inch in diameter fell in the city.  Precipitation was only 0.10 inch.

In 1887…south winds were sustained to 41 mph.

In 1900…a thunderstorm produced northwest winds to 51 mph with gusts to 61 mph…but only a trace of rain.

In 1923…a severe thunderstorm pelted the city with hail. The stones ranged in diameter from 0.2 to 0.8 inch. Gardens and greenhouses suffered considerable damage. Rainfall was only 0.14 inch downtown.

In 1960…one workman was killed and 4 others injured in Lakewood when a partly built apartment building collapsed in strong winds.  Microburst wind gusts to 54 mph caused some blowing dust at Stapleton Airport.

In 1967…tornadoes touched down briefly 3 miles west of Franktown and 4 miles northeast of Parker.  No damage was reported.  Numerous funnel clouds were reported over south metro Denver…one 5 miles south of Denver…one 2 to 3 miles north of Castle Rock…and two near Littleton.

In 1968…a microburst wind gust to 52 mph was recorded at Stapleton International Airport.

In 1972…1 3/4 inch hail was reported in wheat ridge.

In 1976…high winds…unusually strong for this late in the season…raked metro Denver.  Wind gusts estimated to 100 mph tore 24 boats from their moorings and damaged a total of 47 boats at Boulder reservoir.  Wind gusts to 82 mph were recorded in Boulder.  The strong winds toppled the wind mast at a radio station in Boulder.  An automobile was smashed by a fallen tree in Boulder.  Other damage in Boulder was minor…but power outages occurred when tree limbs fell on  power lines.  At Jefferson County Airport near Broomfield…wind gusts to 78 mph were recorded with 87 mph gusts clocked at Rocky Flats nuclear plant south of Boulder.  Wind gusts to 66 mph were observed in Littleton… And northwest winds gusted to 46 mph at Stapleton International Airport.  The strong winds collapsed a barn near Arvada.  Several horses received minor injuries. Thirty trees were uprooted or broken in Denver.  Four major power outages occurred from west Denver and Lakewood to the foothills.

In 1982…the worst hailstorm in 17 years struck Commerce City.  The storm left 4 to 8 inches of hail on the ground. A few of the stones were as large as golf balls.  Many vehicles were dented…and some windshields were shattered. Roofs of homes were damaged.   Total damage was estimated at over one million dollars.  Hail to 1 inch in diameter also fell in Littleton.  Only 1/4 inch hail was measured at Stapleton International Airport.

In 1988…lightning ripped a small hole in the roof of a home in the southern part of Boulder.  There were some power outages in the area.

In 1992…an off duty national weather service employee reported hail to 1 inch diameter in Westminster.

In 1997…one inch diameter hail fell in Bennett…and 3/4 inch hail was measured in Littleton.

In 1999…hail as large as 1 1/2 inches in diameter hit Aurora. Lightning sparked two small fires at separate residences near the Hiwan Country Club in Evergreen.

In 2004…lightning sparked two small fires near Jamestown. One was in Geer Canyon and the other 7.5 miles up sunshine canyon.  Both were quickly contained and caused no damage to structures in the area.

In 2009…a complex of severe thunderstorm produced large hail damaging thunderstorm and funnel clouds across parts of the urban corridor.  The line formed along a boundary over the western suburbs of Denver then moved east. The boundary produced at least one well defined funnel cloud that could be observed by stadium full of baseball fans at Coors Field.  Large hail…up to 1 3/4 inches in diameter…was reported in Arvada…Broomfield…Denver…Federal Heights and Northglenn.  In addition…the storm produced peak wind gusts from 60 to 74 mph.  At Denver International Airport…a peak wind gust to 58 mph was observed from the west-northwest.

In 2014…severe thunderstorms broke out across the Urban Corridor. Large hail…ranging in size from 1 to 2 inches in diameter…was observed. The area extended from around Englewood to Aurora and included: Brookridge…Cherry Knolls… Greenwood Village and south Denver. As many as 212 thousand residences were potentially impacted by the storms. The hail shattered windshields and damaged vehicles.

Continue reading June 13 to June 19: This week in Denver weather history →

Weather History

June 6 to June 12: This week in Denver weather history

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This Week in Denver Weather History

An extremely eventful week in weather history showing just how varied conditions can be.  We of course see typical spring weather like tornadoes and hail but also a touch of snow and this week also marks the anniversary of the start of the Hayman Fire.

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In 2012…it was the hottest June in Denver since weather records began back in 1872. The average temperature for the month was 75.0 degrees which was 7.6 degrees above normal. There were a total of seventeen 90 degree days in the month of June. The highlight of record setting month was a stretch of five consecutive 100 degree days from the 22nd to the 26th. This was only the third time in Denver weather history in which this happened. Two of the high temperatures during the stretch peaked at 105 degrees… Which set the all-time record for the month of June and tied the all-time maximum temperature for Denver.

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In 1921…heavy rainfall for nearly a week…on top of streams already swollen by mountain snowmelt…produced widespread flooding over the South Platte River basin…including the tributaries through the canyons to the west and southwest of Denver.  Heavy rainfall over the 6-day period totaled 3.36 inches in Boulder…4.98 inches in Morrison…4.27 inches in Castle Rock…and 2.94 inches in the city of Denver. Rainfall amounts in the foothills were estimated between 3 and 6 inches.  The narrow-gage tracks of the Colorado and southern railroad were destroyed in the Platte Canyon.  From the mouth of the canyon through the city to near Brighton… The river spread from 1/2 to nearly 1 1/2 miles wide… Flooding farm and pasture land and destroying or damaging many bridges.  In the city…many businesses along with as many as 500 homes were inundated…forcing their evacuation. Bridges were swept away.  The high waters flooded the rail yards and stock yards in lower downtown…closing three adjacent packing houses.  The heavy rains also caused flooding on Boulder creek in Boulder on the 6th.

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In 1977…lightning caused several power outages and moderate damage to a railroad building.

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In 1954…thunderstorm winds at speeds of 50 mph with gusts as high as 59 mph briefly reduced the visibility to 1 mile in blowing dust at Stapleton Airport.

In 1967…the public reported golf ball to 1 3/4 inch diameter hail in the city…3 miles west-southwest of Stapleton International Airport. The amount of damage was unknown. Thunderstorm winds gusted to 46 mph at Stapleton International Airport.

In 1981…hail to 3/4 inch in diameter was reported in east Denver.

In 1990…golf ball size hail was reported near Strasburg on I-70 east of Denver.

In 1991…a tornado was spotted by national weather service personnel and weather spotters…14 to 17 miles northeast of Stapleton International Airport. A funnel cloud was sighted over south Aurora just east of Buckley Field…and a tornado was spotted just east of Watkins. No damage was reported. Thunderstorms moved through Aurora and dropped hail up to 1 inch in diameter. The storms also produced heavy rain… Up to 1 inch in 30 minutes…causing flooding of streets. Water was reported hood deep…stranding motorists. Water covered fire hydrants at some intersections.

In 1995…a waterspout sighted over Standley Lake in northern Jefferson County…quickly dissipated once it reached shore. A brief tornado…which was momentarily visible by a dust debris cloud on the ground…damaged the roof of a house in Westminster. A funnel cloud was sighted just south of Lafayette. Hail from 3/4 to 1 1/4 inches in diameter fell over north Boulder. Thunderstorm outflow produced north wind gusts to 44 mph at Denver International Airport.

In 1997…a tornado touched down near baseline reservoir just east of Boulder. The tornado struck a home…tearing off part of the roof. A storage building nearby was nearly leveled and 5 trees were uprooted. The twister then moved onto baseline reservoir…forming a huge waterspout. Several recreational vehicles and a boat dock were also damaged. A nearly stationary line of thunderstorms dumped 4.60 inches of rain on portions of Thornton. Extensive flooding of streets and underpasses and other low lying areas was reported. Several businesses were flooded and basements in the area were damaged. Rainfall totaled 1.02 inches at Denver International Airport and 1.24 inches at the site of the former Stapleton International Airport. Large hail…up to 1 3/4 inches in diameter…fell over the city of Denver with 3/4 inch hail measured in Littleton and near Henderson.

In 1999…high winds developed for a brief time in and near the foothills of Boulder. The Gamow Tower on the University of Colorado campus recorded a wind gust to 87 mph. Winds peaked to 71 mph atop Niwot Ridge near the continental divide west of Boulder.

In 2003…a small tornado touched down near Strasburg…but did no damage.

In 2012…severe thunderstorms broke late in the evening…striking areas hardest from Denver southward. Locations impacted by the storms included but were not limited to: Aurora…Castle Rock…Centennial…Highlands Ranch…Lone Tree…Parker and Surrey Ridge. The storms produced a barrage of
large hail…damaging straight line winds…flash flooding and several short lived tornadoes. The hail ranged in size from 1 to 2 inches in diameter…and caused extensive damage to homes and automobiles. The hail inundated the roadways with several inches of hail in Douglas County. Consequently…snow plows had to be called out to clear the roadways. The combination of torrential hail and heavy rain produced flash flooding in parts of Elbert…Douglas and Arapahoe Counties…as thunderstorms brought up to 3.35 inches of rain to some areas within 90 minutes. In Aurora…Picadilly Road was closed from flooding north of 6th Avenue. A water rescue took place on South Gun Club Road in Arapahoe County…where floodwaters were rushing to depth of 3 feet. Flash flooding forced the closure of several streets and roads from Parker south to The Pinery…where the floodwaters inundated the roadway with up to 2 feet in several locations.  At Centennial Airport…a historic B-17 Flying Fortress suffered extensive damage as hailstones as large as ping pong balls struck the aircraft. Although the airframe itself did not require repair…the fabric-covered ailerons and elevators were extensively damaged. The hail came straight down and punched holes in the fabric-covered control surfaces. The aircraft landed just hours before the storm hit to participate in a weekend tour stop.  Lightning also struck two homes…one in Lakewood and the other in Parker. Straight line winds downed trees and power lines in Aurora. As a result…scattered electrical outages affected around five thousand residents.  At Denver International Airport…0.61 inches rainfall was recorded along with a peak wind gust of 41 mph.

In 2016…powerful thunderstorms fired up along the urban corridor and produced damaging hail…strong outflow winds… heavy rain and lightning. Golf-ball size hail in Highlands Ranch caused extensive damage including broken windows on homes and windshields on vehicles. Heavy rainfall…also produced street flooding. In and around Highlands Ranch… anywhere from 2.3 to 2.8 inches of rainfall was observed… with 1 to 1.5 inches around metro Denver. At Denver International Airport…0.38 inches of rainfall was recorded.

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In 2004…a brief hot spell produced 3 temperature records. High temperatures of 95 degrees on the 6th and 98 degrees on the 7th were record maximum temperatures for the dates. Low temperature of 68 degrees on the 7th was a record high minimum for the date.

In 2007…an unusually strong storm system brought very strong winds to the Front Range foothills and urban corridor. Peak gusts included:  92 mph at Boulder…85 mph…2 miles southwest of Boulder…83 mph…10 miles south of Boulder and 55 mph at Denver International Airport.  High winds forced the closure of Mt. Evans Road and Trail Ridge Road.  Several trees were uprooted across the urban corridor.  In Aurora… The driver of a car was injured when some building material blew off the Fitzsimmons complex.  The debris landed on the car and knocked the driver unconcious.  The wind forced the cancellation of 60 flights at Denver International Airport. Xcel reported outages in Boulder…Denver…Lakewood and Longmont.

In 2012…severe thunderstorms broke late in the evening… Striking areas hardest from Denver southward. Locations impacted by the storms included but were not limited to: Aurora…Castle Rock…Centennial…Highlands Ranch…Lone Tree… Parker and Surrey Ridge. The storms produced a barrage of large hail…damaging straight line winds… Flash flooding and several short lived tornadoes. The hail ranged in size from 1 to 2 inches in diameter…and caused extensive damage to homes and automobiles. The hail inundated the roadways with several inches of hail in Douglas County. Consequently… Snow plows had to be called out to clear the roadways. The combination of torrential hail and heavy rain produced flash flooding in parts of Elbert…Douglas and Arapahoe counties…as thunderstorms brought up to 3.35 inches of rain to some areas within 90 minutes. In Aurora…Picadilly Road was closed from flooding north of 6th Avenue. A water rescue took place on south Gun Club Road in Arapahoe County…where floodwaters were rushing to depth of 3 feet. Flash flooding forced the closure of several streets and roads from parker south to the Pinery…where the floodwaters inundated the roadway with up to 2 feet in several locations. At Centennial Airport…a historic B-17 Flying Fortress suffered extensive damage as hailstones as large as ping pong balls struck the aircraft. Although the airframe itself did not require repair…the fabric-covered ailerons and elevators were extensively damaged. The hail came straight down and punched holes in the fabric-covered control surfaces. The aircraft landed just hours before the storm hit to participate in a weekend tour stop. Lightning also struck two homes…one in Lakewood and the other in Parker. Straight line winds downed trees and power lines in aurora. As a result…scattered electrical outages affected around five thousand residents. At Denver International Airport… 0.61 inches rainfall was recorded along with a peak wind gust of 41 mph.

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In 1904…a thunderstorm produced south winds to 40 mph with gusts to 50 mph…but only a trace of rain.

In 1942…heavy thunderstorm rainfall in south Denver caused flooding of shops…stalled motorists…and halted tramway service temporarily.  Lightning damaged houses…but there was no loss of life.  Precipitation totaled 0.53 inch in downtown Denver.

In 1951…a 24×65 foot roof of a cow barn was lifted off the building and blown to the ground by a “twister” near Fort Lupton.

In 1961…small hail and heavy rain damaged property and crops in southwest metro Denver…including the southwest section of the city…Lakewood…and Littleton.  Precipitation totaled 1.20 inch…11 miles southwest of Stapleton Airport. Complete primary and secondary rainbows were sighted by national weather service observers at Stapleton Airport.

In 1968…severe thunderstorms moving to the northeast through sections of Denver caused local flooding of streets and damage to trees and gardens from hail 1/2 to 1 3/4 inches in diameter.  One man was killed and 2 were injured at the Wellshire Golf Course when lightning struck a tree under which they had taken shelter.  At another golf course… A man was mortally injured by lightning.  Marble to golf ball size hail fell over downtown Denver.  Hail to 3/4 inch in diameter was measured in Westminster.

In 1975…hail up to 3/4 inch diameter fell in Boulder.

In 1978…a man standing under a tree on a golf course in Denver was struck in the arm by lightning.   Wind gusts to 60 mph and golf ball size hail pelted west and south Denver.

In 1986…7/8 inch hail was measured in Lafayette.

In 1990…a thin…rope-shaped tornado touched down east of the intersection of State Highway 2 and 96th avenue just north of the rocky mountain arsenal.  No damage was reported.

In 1992…a thunderstorm wind gust to 60 mph was recorded in Boulder.  A funnel cloud was sighted by a highway patrol officer just northwest of Stapleton International Airport where thunderstorm winds gusted to 51 mph.  Spotters and state patrol officers reported funnel clouds in the northwestern part of metro Denver…near Golden…and 7 miles northwest of Stapleton International Airport.

In 1993…non-convective high winds pummeled the Front Range foothills during the late morning and afternoon.  Speeds of 60 to 80 mph were common.  The winds caused several power outages as well as uprooting trees.  In Lafayette…a 4-year- old boy was slightly injured while standing on the roots of a large tree which was toppled by the winds.  The boy fell 10 feet to the ground and was bruised and scraped.  A tree fell onto a parked car in Boulder…causing about 35 hundred dollars in damage.  West wind gusts to 41 mph were recorded at Stapleton International Airport where a thunderstorm produced 1/8 inch hail at daybreak.

In 1995…severe thunderstorms produced large hail across west and north metro Denver from Golden to Westminster and Fort Lupton.  Hail ranged in size from 3/4 to 2 inches in diameter.  The largest hail fell in Fort Lupton.  A weak tornado produced a brief dust and debris cloud in a corn field 3 miles northeast of Hudson.

In 1997…two plumbers were injured…one critically…when lightning struck a pipe on which they were working in an apartment building under construction in Denver.  The bolt apparently hit one man in the hand…passed through his chest…and struck the other worker.  The critically injured man…died a few days later.  Lightning also injured a man…while he was talking on a telephone in ward.  The bolt passed through the phone line burning his ear.

In 2001…hail as large as 7/8 inch in diameter fell in Westminster.

In 2012…severe thunderstorms brought damaging wind and hail…heavy rain and flash flooding. The storms produced hail from 1.5 to 2.5 inches in diameter. In addition to the large hail…heavy rain from 1 to 2 inches also accompanied the storms. The combination of hail and heavy rain caused extensive street flooding across Aurora…Castle Rock…Centennial…Cherry Creek… Englewood…south Denver…Highlands Ranch… Lakewood and Littleton. The hail was reportedly “knee deep” in several areas making roads impassable. As a result… Snow plows had to be summoned to clear the streets. In Castle Rock…a King Soopers supermarket sustained extensive damage when roof partially collapsed under the weight of the hail. At Denver International Airport…0.61 inches of rainfall was again recorded along with a peak wind gust of 40 mph. Total property damage estimates along the Front Range for the 6th and 7th combined was 321.1 million dollars.

In 2016…large hail up to 1 inch in diameter was observed in Castle Rock.

Continue reading June 6 to June 12: This week in Denver weather history →

Weather History

May 30 to June 5: This week in Denver weather history

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This Week in Denver Weather History

There are many notable events on our look back at the weather history books for this week but one in particular stands out. It was 30 years ago this week, on June 3, that the infamous Thornton tornado struck. This twister still stands as the most damaging tornado to have ever struck the Denver metro area.

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In 1995…a cool period with light morning showers and moderate to heavy afternoon showers and thunderstorms pushed rivers already swollen from mountain snow melt over their banks causing minor flooding. Streams and rivers such as the South Platte and Boulder creek flooded meadowlands…bike paths…roads near streams…and other low lying areas. No significant property damage was reported and crop damage was unknown. Rainfall totaled 1.79 inches at the site of the former Stapleton International Airport and only 1.51 inches at Denver International Airport.

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In 1894…heavy rain combined with snowmelt runoff caused widespread flooding over the South Platte River basin. Rainfall was heaviest in the foothills where 5 to 8 inches were measured over the 4 days. Heavy rainfall west of Boulder flooded mining towns and damaged mining properties. In the canyons above Boulder…railroads and roads were washed out along with many bridges. The floodwaters spread into central Boulder and covered a wide area from University Hill north to near Mapleton Hill to a maximum depth of 8 feet. Many houses were swept away…and every bridge in Boulder was destroyed. A few people…trapped in their homes by the floodwaters… Had to be rescued. However…the gradual rise of the flood waters resulted in only one death. Boulder creek spread to a width of nearly one mile in the pasture land to the east of Boulder. Extensive flooding on left hand creek north of Boulder washed away railroad and wagon bridges. The heavy cloudbursts caused flooding on bear creek…which washed away bridges…railroad tracks…and structures and destroyed the canyon roadway. Morrison sustained the heaviest flood damage on bear creek. In Denver…rainfall totaled only 1.50 inches on the 30th and 31st…but the heavy rainfall on upstream tributaries of the South Platte River caused the river to rise as much as 10 feet above the low water mark in the city…which caused some flooding of pasture land downstream to a depth of 6 feet near Brighton.

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In 1875…a windstorm lasting almost all day produced sustained winds to 42 mph.

In 1935…southeast winds sustained to 29 mph with gusts to 34 mph produced a moderate duststorm during the afternoon.

In 1938…heavy thunderstorm rain and hail pummeled downtown Denver during the evening hours. Rainfall accumulated to 1.63 inches. Hail accumulated to a depth of 18 inches.

In 1948…a localized thunderstorm caused flooding on sand creek in Aurora and northeast Denver. Rainfall was only 0.49 inch in downtown Denver where light hail also fell.

In 1963…a golfer died of injuries received when struck by lightning on a golf course southwest of Denver. A warehouse in Denver was damaged and its contents destroyed by a lightning-caused fire.

In 1967…up to 4.00 inches of rain in Lakewood and wheat ridge caused flooding of roads and basements. Water was several feet deep in some yards. Many streets were temporarily closed. Hail as large as 1 inch in diameter fell in Wheat Ridge. Hail piled up to 2 feet deep in some low lying areas of east and southeast Denver. Snowplows were employed to remove the hail. Stapleton International Airport…where west winds gusted to 39 mph…received 1.51 inches of rain and hail…which forced the closure of the runways for an hour. Hail stones to 3/4 inch in diameter were measured at Buckley Field. A funnel cloud was sighted near south Wadsworth Blvd and Bear Creek. A tornado touched down briefly in the vicinity of 60th and 62nd avenues near north Washington Street. The storm uprooted trees and damaged one building. Doors were ripped from a business house…widely scattering irrigation pipe. In addition…a total of 3 funnel clouds were sighted in that area.

In 1970…hail up to 1 inch in diameter fell at Stapleton International Airport.

In 1976…a single thunderstorm crossed south metro Denver producing a funnel cloud 2 miles south of Arapahoe road and Broadway. The storm moved over Buckley Field producing a funnel cloud and 1/2 inch diameter hail. As the storm moved northeast of the city…a large tornado touched down near east 59th Ave and tower road and was on the ground for 20 minutes. It demolished a 60-foot-long cinderblock cow shed…tore a wall from a machinery shed…tore shingles off the roof of a farmhouse nearby…and felled 12 trees on one farm. A boy in a feed shed 20 feet from a destroyed building was not injured.

In 1977…3/4 to 1 inch diameter hail fell at or near Stapleton International Airport. One inch to baseball size hail fell in south Denver…damaging some homes and extensively damaging some airplanes at Arapahoe County airport…now centennial airport. Hail covered highways to a depth of 6 to 8 inches in south Denver.

In 1978…two funnel clouds were sighted 5 miles south of Stapleton International Airport. Hail up to 1 1/4 inches in diameter was reported in wheat ridge and northwest Denver. Only 1/2 inch diameter hail fell at Stapleton International Airport.

In 1989…golf ball size hail fell at the junction of I-25 and I-225. One inch diameter hail fell in Littleton.

In 1990…a line of severe thunderstorms crossed metro Denver… Producing wind gusts to 60 mph and scattered areas of pea to marble size hail. Small trees and branches were blown down by the strong thunderstorm winds…which also caused minor power outages across southern and eastern sections of metro Denver. The strong winds uprooted a 25- to 30-foot tree in the acres green subdivision of northern Douglas County. The tree blocked a busy street for several hours. A pilot reported hail as large as 1 1/2 inches in diameter covering the ground near the north end of a runway at Stapleton International Airport. Heavy rain caused a rock and mud slide that partially closed the Boulder canyon highway 10 miles west of Boulder. Thunderstorm winds gusted to 41 mph at Stapleton International Airport.

In 2001…lightning ignited a fire which destroyed a luxury home on bear mountain near Evergreen. Estimated damage was set at 1 million dollars.

In 2003…flash flooding occurred in the Hayman Fire burn area after as much as 1 inch of rain fell in 30 minutes. The heavy rainfall washed out many access roads and closed State Highway 67 between Deckers and west creek. A 3-foot wall of water ran down Fourmile Creek from the YMCA camp at Shady Brook…damaging one building in the camp and flooding roads. Hail as large as 3/4 inch in diameter fell near Roggen in weld County.

In 2005…lightning struck as least 20 homes in Westminster. Only minor damage was reported. Severe thunderstorms produced hail as large as 1.25 inches in and near Fort Lupton and hail to 3/4 inch near Indian Hills in Jefferson County.

In 2014…heavy rainfall…nearly 1.2 inches in 30 minutes… produced localized street flooding in Boulder. The heavy rain coupled with the already swollen creeks from the spring runoff along Boulder Creek resulted in the flooding. Street flooding was reported at 6th St and Canyon Blvd and at Baseline Road. Some cars were stranded in the high water in low lying areas and one person reported being trapped in his vehicle.

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In 1935…heavy thunderstorm rains overnight caused flash flooding east of the city on both Kiowa and Bijou Creeks… Resulting in a total of 9 deaths. Most of the damage was on Kiowa Creek where there were more structures. The water rose rapidly during the storm…ripping houses and stores from their foundations and sweeping them downstream. Precipitation in Denver totaled only 0.01 inch. Hail fell in the city for a short time. The hail was very small and caused no damage.

In 1983…a late storm of rain and snow hit the Front Range. Over an inch of rain fell at some spots…and above 7 thousand feet…1 to 5 inches of snow whitened the ground. Some snowflakes even fell in the western suburbs of metro Denver on the night of the 30th.

In 2002…unseasonably warm weather at the end of the month resulted in 3 temperature records. High temperature of 91 degrees on the 30th equaled the record maximum for the date. Low temperature of 61 degrees on the 31st was a record high minimum for the date. High temperature of 93 degrees on the 31st was a record maximum for the date.

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Weather History

May 23 to May 29: This week in Denver weather history

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This Week in Denver Weather History

We are getting closer to Colorado’s severe weather season and see how dangerous it can be when we look back in Denver weather history.  Many occurrences of dangerous lightning, large hail, flooding and tornadoes have been the hallmark of this week in Denver weather history.

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In 2002…lightning sparked a wildfire near Deckers.  Extremely dry conditions and very strong winds the following day allowed the fire…known as the schoonover…to consume 3850 acres before it could be contained.  Thirteen structures were destroyed…including 4 homes…resulting in 2.2 million dollars in damage.

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In 1876…snow changed to heavy rain over the city…resulting in widespread flooding along Cherry Creek and the South Platte River…nearly as great as the flash flood of May 19-20…1864.  However…damage was greater because the city had grown much larger and there were more bridges for the flood waters to destroy.  Precipitation in the city totaled 6.70 inches from 10:00 pm on the 21st through 3:00 am on the 23rd.  The greatest precipitation ever recorded in Denver in 24 hours…6.53 inches…occurred on the 21st and 22nd.  Small buildings and bridges along Cherry Creek were washed away by the flood waters.  Bridges over the South Platte River were damaged.  The city irrigation ditch was damaged and rendered unfit for service.  Strong winds at speeds of 30 to 40 mph drove the heavy rain through brick walls 12 to 16 inches thick.  Many sheep and cattle were either killed by lightning or drowned…including some 100 head of cattle in Jefferson County alone.  There was immense damage to railroad tracks…especially the Kansas Pacific line to the east of the city.  The Colorado Central suffered estimated damage of 10 to 15 thousand dollars.  In addition…the heavy rain caused extensive flooding on soda and bear creeks in the foothills.  Flooding along Boulder creek inundated farm and pasture land in the Boulder valley and damaged a few bridges.  Rail travel had to be suspended in the area for several days.

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In 1933…high winds and gales overnight caused considerable damage in and near the city.  Much greenhouse glass was broken…which caused damage to sheltered plants.  Great numbers of plants growing in the open were damaged or killed by wind-driven sand and soil.  Fields were eroded by the wind and a few trees were uprooted.  West winds were sustained to 38 mph with gusts as high as 65 mph in downtown Denver on the 22nd.

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In 1916…southeast winds were sustained to 43 mph with gusts as high as 52 mph.  The winds were strong for several hours during the afternoon.

In 1965…thunderstorm outflow wind gusts to 59 mph were recorded at Stapleton International Airport.

In 1987…slow moving thunderstorms bombarded metro Denver. One inch diameter hail was reported in south central Denver.  Torrential rain caused widespread street flooding… Stalling traffic throughout the area.  Rainfall totaled 2.10 inches in just 25 minutes in extreme southeast Aurora. Many other locations in Aurora and east Denver reported 1 to 1 1/2 inches of rain in about 30 minutes.  Thunderstorm rainfall totaled 1.33 inches at Stapleton International Airport where 1/4 inch diameter hail was measured and north winds gusted to 40 mph.  A man was slightly injured by lightning near Stapleton International Airport.  Lightning also started a fire that severely damaged a house in Aurora.

In 1990…a microburst wind gust to 52 mph at Stapleton International Airport produced some blowing dust.

In 1991…thunderstorms moving from southwestern sections of metro Denver to the east of Denver produced large hail up to golf ball size.  An estimated 5 thousand homes and 8 thousand cars received considerable damage.  Early estimates placed damage costs around 60 million dollars. Three funnel clouds were also reported…two by personnel at Buckley Field and the other by a storm spotter.  Heavy rain produced street flooding in Aurora where hail accumulated to a depth of 6 inches.  As the storms moved to the east…golf ball size hail was reported at Strasburg.

In 1997…hail to 3/4 inch diameter fell in Broomfield.

In 2002…a very strong microburst near Strasburg swept a woman into a swirl of dirt and carried her about 150 feet. The woman was in an open field…corralling a yearling horse… When the incident occurred.  Fortunately…she received only minor injuries.

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In 2002…a pacific storm system brought much needed snow to the mountains and foothills with a mix of rain and snow on the plains.  The most snow fell from central Jefferson County northward.  Snow totals included:  13 inches in Coal Creek Canyon…11 inches near Evergreen and atop gold hill… 10 inches near Blackhawk and conifer and atop Crow Hill… 9 inches near Rollinsville…and 8 inches near Genesee and Golden.  Rain was mixed with snow across the city. Precipitation totaled 0.61 inch at Denver International Airport.  Snowfall was less than an inch at the site of the former Stapleton International Airport.  The storm brought unseasonably cold air to metro Denver.  Three temperature records were set.  Low temperature of 31 degrees on the 23rd was a record minimum for the date…as was the low of 32 degrees on the 24th.  The high temperature of only 48 degrees equaled the record low maximum for the date.

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In 1953…a microburst caused a brief wind gust to 55 mph at Stapleton Airport.

In 1957…walnut size hail…1 1/2 inches in diameter…fell in east Denver.  Only 1/4 inch hail was measured at Stapleton Airport.

In 1958…rainfall totaled 1 to 2 inches across metro Denver. Rainfall was only 0.37 inches at Stapleton Airport.

In 1974…a tornado was observed briefly near Watkins.  No damage was reported.

In 1980…strong gusty winds of at least 60 mph damaged buildings in parts of Denver.  Several buildings were unroofed in Sheridan.  The flying debris damaged other structures.  Strong microburst winds gusted to 52 mph at Stapleton International Airport.

In 1991…a tornado touched down briefly in open country near Bennett.  No damage was reported.

In 1994…weather spotters reported 2 funnel clouds over Aurora and a short-lived waterspout on Cheery Creek Reservoir.

In 1997…hail to 1 inch in diameter fell in Broomfield with 3/4 inch hail measured in Boulder.

In 1998…a tornado struck a wooden hangar at the Aurora airpark.  The hangar collapsed…damaging a car and a single engine plane parked inside.  An adjacent steel hangar sustained only minor damage.  The tornado moved northeast…hopped I-70…and touched down again in an open field.  Earlier…a weak tornado touched down briefly in an open field 10 miles southeast of Buckley Field.

In 2003…severe thunderstorms produced large hail over northern and southern metro Denver.  Hail as large as 2 3/4 inches in diameter was measured 10 miles northwest of Hudson and to 2 inches in diameter 10 miles northeast of Fort Lupton.  One inch diameter hail fell in Fort Lupton.  Hail to 1 inch in diameter fell near Parker and to 3/4 inch near Franktown.

In 2004…severe thunderstorms moved across northwest and north metro Denver.  Hail as large as 1 inch in diameter fell in Broomfield and Thornton with 3/4 inch hail measured near Arvada and Hudson and in the city of Denver.

In 2005…severe thunderstorms produced hail as large as 1 inch in diameter in Arvada and the city of Denver.

In 2014…a severe thunderstorm in Lakewood produced hail… up to 1 inch in diameter.

In 2016…a long-lived supercell formed over south Denver and tracked across northeast Adams and continued to produce severe weather as into moved into Yuma County. The length of its path was approximately 121 miles. The storm produced hail up to 1.5 inches in diameter in southeast Denver. As it moved across northeast Adams County…several power poles were sheared off at the base by straight-line winds to 80 mph southwest of Leader. The damage path became more extensive as the storm moved into the northeast plains of Colorado. At Denver International Airport…1.15 inches of precipitation fell which set a new daily precipitation record. The storm produced heavier rainfall on one to two inches east of Denver…with over 4 inches in central Arapahoe County.

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In 1996…a late spring snowstorm dumped 4 to 10 inches of snow over the Front Range foothills.  Conifer picked up 10 inches of new snow; Aspen Springs…9 inches; and central city…8 inches.  The sticky…heavy snow clung to power lines and pulled tree branches down…causing power outages to about 1200 homes in the conifer area.  It took up to 6 hours to restore power to some residences. Lightning struck a telephone data cabinet in conifer on the 25th…which knocked out phone service to about 1500 customers.  Widespread rain fell across metro Denver… Where rainfall totaled 2.07 inches at the site of the former Stapleton International Airport and 1.66 inches at Denver International Airport where north winds gusted to 24 mph on the 26th.

In 2010…from the 24th to the 26th…high winds preceding a cold front…swept across the Front Range Foothills and Urban Corridor.  In Aurora…the wind damaged the roof of Rangeview High School.  In Conifer and Denver…the wind downed trees and power lines and caused several brief outages.  The downed power lines also caused several cars to catch fire in the vicinity of 1590 Cook St. in Denver. Peak wind gusts included:  82 mph at Highlands Ranch…67 mph…4 miles east of Franktown and Longmont; 65 mph in Boulder…64 mph in Centennial and Denver International Airport…62 mph near Parker and 60 mph in Arvada.

Continue reading May 23 to May 29: This week in Denver weather history →

Weather History

May 16 to May 22: This week in Denver weather history

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This Week in Denver Weather History

Late spring typically brings some of the most eventful weather Denver sees throughout the year and our look back at this week in Denver weather history shows that.  There are many typical events we would expect to see such as hail, heavy rain and flooding, and even tornadoes.  Most notably, this week marks the two year anniversary of the Windsor tornado.  And, for those that think the snow is done, we can see that in 1983 a snowstorm struck the city forcing the closure of Stapleton International Airport.

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In 1996…a period of unusually warm weather resulted in 4 record maximum temperatures in 5 days.  The record high temperatures were 87 degrees on the 14th…89 degrees on the 15th…and 93 degrees on both the 16th and 18th.  The temperature climbed to only 81 degrees on the 17th which was not a record.

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In 1957…heavy snowfall totaled 8.8 inches at Stapleton Airport. The greatest amount on the ground was 3 inches.

In 1986…a spring storm dumped 1 to 2 inches of rain over metro Denver…but 2.71 inches fell at Buckley Field in Aurora.  Rainfall only totaled 0.84 inch at Stapleton International Airport.  Snow fell in the foothills with 7 inches recorded in Coal Creek Canyon southwest of Boulder.

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In 1875…a heavy hail storm turned into heavy rain during the afternoon.  Rainfall totaled 0.86 inch in just 37 minutes…while the temperature dropped 22 degrees in 22 minutes.  Precipitation totaled 0.90 inch.

In 1894…west winds were sustained to 48 mph with gusts to 56 mph.

In 1949…a tornado was observed for 16 minutes…20 miles to the southeast of Stapleton Airport.  The tornado moved 5 miles to the northeast before dissipating.  No damage was reported.

In 1963…intense lightning started several forest fires in the foothills southwest of Denver near Deckers and Cheeseman Lake.  Little precipitation fell from the storms to alleviate the unusual dry conditions so early in the season.

In 1978…thunderstorm winds caused damage in southeast Aurora.  Winds of 60 to 80 mph blew down numerous fences and damaged several homes under construction.  High winds tore docks loose at Cheery Creek Reservoir…sinking 3 or 4 boats and damaging about 15 others.  At Stapleton International Airport where winds gusted to 60 mph…a 727 jet suffered 15 hundred dollars damage when wind toppled a runway light onto it.  The public reported an unconfirmed tornado 7 miles south-southwest of Stapleton International Airport.

In 1990…a line of thunderstorms moving across metro Denver uprooted a large ash tree…which fell and blocked the outside doors to a Denver elementary school…briefly trapping the students inside.  Thunderstorm wind gusts to 69 mph were reported at Jefferson County Airport. Northwest winds gusted to 44 mph at Stapleton International Airport.

In 1991…two tornadoes touched down briefly in Castle Rock… But no injuries or damage were recorded.  Heavy thunderstorm rains of 0.50 to 1.10 inches in a couple of hours caused Lena Gulch near Golden to flood.  No damage was reported.

In 1996…dry microburst winds of unknown strength overturned a trailer and damaged storage sheds in Strasburg east of Denver.

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In 1981…a heavy rain storm dumped 1 to 2 1/2 inches of rain across metro Denver.  Rainfall totaled 1.27 inches at Stapleton International Airport where north winds gusted to 38 mph on 17th.

In 1983…a very strong late spring storm dumped heavy snow over the Front Range.  Strong winds with the storm produced blizzard conditions at times.  Sustained winds were 20 to 40 mph with a peak gust to 55 mph at Stapleton International Airport.  The foothills received 1 to 2 feet of snow with 4 to 12 inches along the foothills.  Howling winds whipped the snow into drifts several feet deep…closing schools and highways.  Stapleton International Airport was forced to reduce flight operations…closing 2 of 4 runways and stranding hundreds of travelers.  Most of the damage and inconvenience caused by the storm was in power outages… Which occurred when wind and heavy wet snow caused hundreds of power poles to snap and topple.  About 20 square miles of Denver were blacked out.  Precipitation from the storm totaled 1 to 3 inches.  At Stapleton International Airport… Snowfall totaled 7.1 inches with a maximum snow depth on the ground of only 2 inches due to melting.  The high temperature of 40 degrees on the 17th was a record low maximum for the date.  Due to the heavy moisture content of the storm…widespread street flooding occurred on the 18th when much of the snow melted under the warm May sun and temperatures climbed to a high of 57 degrees.

In 1995…significant moisture and upslope flow caused flooding across metro Denver.  Moderate to heavy rains… Which began on the evening of the 16th…developed in the foothills and spread eastward over metro Denver throughout the night.  The heavy rains brought many creeks and small streams to bankfull or slightly over.  Locations along the foothills received between 3 and 4 inches of rainfall from the storm.  Boulder received 3.60 inches of rainfall for the 24-hour period…causing minor street flooding near small streams.  To the northwest of Boulder…a bridge which crossed Fourmile Creek was washed out.  Numerous rock and mudslides occurred in foothills canyons…closing portions of U.S. Highways 6 and 40 and State Highway 119 for a few hours at a time.  Rocks were piled 6 feet deep on a stretch of State Highway 119 along with Boulders as large as cars on U.S. Highway 6.  A parking lot near a creek in Golden caved in leaving a hole the size of an 18-wheeler.  Rushing water washed out a 50-foot stretch of a road in Westminster. Rainfall totaled 1.75 inches at Denver International Airport…but only 1.42 inches at the site of the former Stapleton International Airport.

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In 1903…southwest winds were sustained to 42 mph with gusts to 45 mph from an apparent microburst which produced only a trace of rain.

In 1960…hail to 3/4 inch diameter was measured in Thornton. Golf ball size hail fell in Arvada.

In 1972…microburst winds gusted to 51 mph at Stapleton International Airport.

In 1975…hail 1/2 to 3/4 inch in diameter fell over western metro Denver.

In 1978…a small tornado touched down in south Aurora damaging 40 homes…6 to a considerable extent.  One garage was demolished and blown across the street.  Parts of roofs were completely blown away.  Several 2×4-inch boards were blown into the sides of houses.  Another small tornado in Parker damaged two airplanes.  Other funnel clouds were sighted over Northglenn and near Golden.

In 1985…a thunderstorm produced a total of 1.50 inches of rain in Brighton where 0.72 inches fell in 40 minutes. Small hail covered the ground…and there was some street and basement flooding.

In 1987…small hail piled up 4 inches deep in southwest Aurora.  There was also widespread street flooding and a few power outages.  Hail as large as 3/4 inch in diameter fell at Castle Rock.

In 2000…high winds occurred along and east of the Front Range foothills…as a deep surface low pressure center formed over the northeast plains of Colorado.  An amusement park in north Boulder received about 25 thousand dollars in property damage.  Peak wind reports included:  88 mph at the national wind technology center…84 mph in Boulder…and 80 mph at the National Center for Atmospheric Research Mesa Laboratory. A powder keg of severe weather…including tornadoes and thunderstorms producing large hail…damaging winds and heavy rain…occurred over the plains to the northeast of Denver.  The only severe weather reported across metro Denver was 1 inch diameter hail in Littleton.

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In 2017…a strong spring storm dropped across the Great Basin… and then moved eastward across Colorado. Isolated but strong thunderstorms preceded the system on the 17th with hail up to nickel size near Boulder Airport and Brighton. Significant snow fell across the Front Range mountains and foothills over the next couple of days. Along the Interstate 25 Corridor… rain turned to snow on the morning of the 18th…heaviest from around Broomfield northward. The heavy wet snow snapped the limbs of fully leaved trees and caused scattered power outages. A barns collapsed in northeast Loveland. Fifty-five head of cattle were inside the collapsed barn; three were injured and later euthanized. Numerous branches and trees snapped in the foothills. Elsewhere…several scattered smaller power outages were reported. Three to nearly five inches of liquid precipitation occurred…as rain or a mix of rain and snow…fell around Greeley. Storm totals in the Front Range mountains and foothills included: 42.0 inches near Allenspark…41.5 inches near Ward…36 inches at Estes Park… 32 inches near Pinecliffe…30.5 inches northwest of Golden… 30 inches near Nederland…26 inches near Breckenridge…25 inches near Aspen Springs and Bear Lake State Park…14 inches at Aspen Springs…with 9.5 inches near Evergreen. On the west side of the Interstate 25 Corridor…storm totals included: 10 inches near Superior and Louisville…6 to 8 inches in and around Fort Collins…6 inches in Lafayette… 5 inches in Broomfield and Loveland…and 4 inches near Niwot.

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In 1864…heavy rains combined with melting snow to cause much flooding on north clear creek in Blackhawk.  Many bridges on the road to Denver were washed away by the high water on clear creek.

In 1893…northwest winds were sustained to 56 mph with an extreme velocity to 60 mph.

In 1960…large hail to 1 inch in diameter damaged roofs and cars in metro Denver.  Heavy snow and rain in the foothills caused rock and landslides…which blocked some highways. There was widespread minor damage from lightning. Hail as large as 1 1/8 inch in diameter was measured at Stapleton Airport where winds gusted to 44 mph.

In 1975…a tornado touched down briefly just south of Buckley Field in Aurora.  A few minutes later the same tornado touched down in open country 8 miles northeast of Stapleton International Airport.  No damage was reported.

In 1985…3/4 inch hail fell just southeast of Aurora.

In 1988…lightning started a fire at a home in the foothills west of Boulder…causing 50 thousand dollars in damage.

In 1995…strong thunderstorms rumbled across metro Denver dropping mainly pea to marble size hail.  However…hail stones as large as 1 1/4 inches in diameter fell in Wheat Ridge and downtown Denver.  Hail piled up to 2 inches deep in Wheat Ridge and northwest Denver.

In 1996…the buffalo creek wildfire started and spread rapidly on strong southwest winds at 20 to 30 mph.  Dry weather conditions contributed to the spread of the fire… Which burned nearly 12 thousand acres and destroyed 12 structures including some houses.

In 2001…a 19-year-old man was struck and killed by lightning as he was walking along the shoulder of U.S. Highway 36 in Westminster.

In 2003…hail to 3/4 inch in diameter was measured at Denver International Airport.

In 2010…a small tornado touched down near Firestone but did no damage.

Continue reading May 16 to May 22: This week in Denver weather history →