July 25 to July 31: This week in Denver weather history

This Week in Denver Weather History

Colorado’s unofficial severe weather season is during the months of May and June.  However, as we look back in Denver weather history, we see that July can oftentimes hold its own.  Many occurrences of flooding, scorching heat, and even tornadoes have been recorded.  Most notably, this week marks the 24th anniversary of the Big Thompson Flood – Colorado’s deadliest weather disaster ever.

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.

13-5

In 2008…a streak of 24 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.

18-2

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.

20-25

In 1965…heavy showers and thunderstorms doused metro Denver with significant rain each day.  Rainfall for the six days totaled 5.16 inches at Stapleton International Airport. Massive rainfall occurred on the 20th…21st…and 25th… Flooding streets and basements and causing streams to overflow.  The heaviest rainfall…2.05 inches…at Stapleton International Airport occurred on the 25th.

24-25

In 2003…maximum temperature of 100 degrees on the 24th was a record high for the date.  Low temperature of 73 degrees on the 25th was a record high minimum for the date.

25

In 1875…brief heavy rain and hail lasted only 5 minutes… But the 1/4 inch diameter hail covered the ground to a depth of 1/2 inch and made the streets look like there had been snowfall.  There was much crop damage…especially to corn…and some sheep were killed.  Precipitation totaled 0.51 inch in the city.

In 1896…a heavy thunderstorm produced sustained northwest winds to 45 mph with gusts to 50 mph and 1.02 inches of rain.

In 1965…a cloudburst dumped 1.99 inches of rain in 30 minutes at Stapleton International Airport.  The storm was accompanied by strong winds gusting to 70 mph.  The heavy rain flooded numerous streets in east Denver and Aurora. One inch diameter hail accompanied a cloudburst…9 miles southwest of Denver.  A funnel cloud was sighted 25 miles northwest of Denver.  In Aurora…there were unofficial reports of 2.30 inches of rain in 40 minutes and 3.30 inches of rain in 30 to 40 minutes.  Rainfall totaled 2.05 inches at Stapleton International Airport.  Rainfall of 2.42 inches for 24 hours on the 24th and 25th was the second greatest on record for July.

In 1977…a tornado touched down briefly in Aurora southeast of Cheery Creek Reservoir.  No damage was reported. A funnel cloud was sighted for 4 minutes by national weather service personnel 10 miles north of Stapleton International Airport near Henderson.

In 1991…heavy rain…up to half an inch in 10 minutes…caused flooding in Westminster…Northglenn…and north Denver where a section of railroad track was washed away.  At Stapleton International Airport…heavy thunderstorm rain totaled 1.85 inches and briefly reduced the visibility to 1/4 mile. Hail to 1/8 inch in diameter was also measured.  A tornado touched down briefly near Fort Lupton.  No damage was reported.

In 1998…heavy monsoonal thunderstorm rains caused flooding and flash flooding in eastern and southern sections of metro Denver…including Englewood and Aurora…when about 2 to 3 inches of rain inundated the area.  Both I-25 and I-70 were closed for 2 to 3 hours as several low lying areas became impassable due to the high waters.  The water was estimated to be 15 feet deep in one flooded underpass along I-25.  As a result…the freeway was closed from south of 6th avenue to university blvd.  Standing water forced the closure of I-70 at gun club road east of Denver.  In Englewood…U.S. Highway 285 was closed…when high water made it impassable.  Several cars were reportedly floating down the roadway near Sheridan Blvd.  In Aurora…the intersection at Yale Ave. And chambers rd. Was flooded by high water up to 4 feet deep when a spillway on the high line canal was breached.  Lightning also knocked out 11 transformers across metro Denver…causing several small fires and scattered power outages.  Flood and flash flooding also occurred north of Strasburg when as much as 2.51 inches of rain fell in an hour.  The deluge resulted in considerable flooding of local streets and County roads.  Torrential rainfall of 2 to 3 inches in less than an hour triggered a flash flood in Virginia Canyon.  County Road 279 between Idaho Springs and Central City was closed for two days to clear debris from mudslides.  Several cars in Idaho Springs were washed off the road…and numerous basements were flooded in town.  Thunderstorm rainfall totaled 2.69 inches at Denver International Airport.

In 2001…lightning struck two homes in Lafayette…damaging the roof and attic of one and shorting out the electrical system in another.  Hail to 1 3/4 inch in diameter was measured 7 miles north of Castle Rock with 3/4 inch hail 7 miles north of Sedalia.

In 2005…heavy thunderstorm rain in the vicinity of the overland wildfire burn scar triggered a mudslide in Jamestown.  Rocks the size of bowling balls…along with silt and mud slid down the mountain into the town.  No one was injured.  One parked car was buried by the debris.

In 2006…heavy thunderstorm rainfall caused flash flooding 1 mile north of the town of Westcreek in southwestern Douglas County.  Several maintenance roads were washed out by the floodwaters.

Continue reading July 25 to July 31: This week in Denver weather history

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

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.

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.

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.

13-5

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.

16-18

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.

18

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.

18-19

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.

18-2

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.

19

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

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

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.

6-23

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.

11

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.

11-12

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

12

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

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

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.

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. The record of 24 consecutive 90 degree or above days was set from July 13th through August 5th…2008.

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.

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.

4-8

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

Thornton’s July weather preview: Summer heat really kicks in, thunderstorms common

July

Change is of course the one constant in Denver’s weather but come July, things actually get pretty consistent.

The standard formula for a day in July is a sunny morning, clouds developing in the late morning and early afternoon. Come mid-afternoon, thunderstorms are rolling off of the foothills and into the metro area and the eastern plains. These storms do occasionally reach severe status containing hail, gusty winds and heavy downpours of rain.

Check out our July weather preview for a complete look at what is in store for the month ahead.

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

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.

27

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.

28

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

June 2021 top shots: Monthly photo slideshow

A landspout tornado touches down between Firestone and Platteville on June 7, 2021. (Brigette Rodriguez)
A landspout tornado touches down between Firestone and Platteville on June 7, 2021. (Brigette Rodriguez)

The month of June typically sees springtime severe weather reach its height of activity in northeastern Colorado.

This affords the opportunity to capture extraordinary images of amazing weather phenomena from monstrous supercell thunderstorms to heavy rain, hail and even tornadoes.

  • Slideshow updated June 29, 2021

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather and nature related imagery.

Sunsets, sunrises, wildlife and of course every type of weather condition are vividly depicted.  June brings some very dynamic weather and the photos are a great way to see the stunning variety.

To learn more about how to send your photo to us for inclusion in the slideshow, see below the slideshow.

[flickr_set id=”72157719376583098″]

What is missing in the slideshow above?  Your photo!

Our monthly photo slideshow is going to feature images that we have taken but more importantly images that you have captured.  The photos can be of anything even remotely weather-related.

Landscapes, current conditions, wildlife, pets, kids.  Whimsical, newsy, artsy.  Taken at the zoo, some other area attraction, a local park, a national park or your backyard.  You name it, we want to see and share it!

Images can be taken in Thornton, Denver or anywhere across the extraordinary Centennial State.  We’ll even take some from out of state if we can tie it to Colorado somehow.

We’ll keep the criteria very open to interpretation with just about any image eligible to be shown in our slideshows.

What do you win for having your image in our slideshow?  We are just a ‘mom and pop’ outfit and make no money from our site so we really don’t have the means to provide prizes.  However you will have our undying gratitude and the satisfaction that your images are shared on the most popular website in Thornton.

To share you images with us and get them included in the slideshow just email them to us or share them with ThorntonWeather.com on any of the various social media outlets.  Links are provided below.

So come on, get those camera’s rolling!

Lightning and wildfires – Hand in hand hazards

Wildfires and lightning go hand in hand as half of Colorado’s blazes are ignited by lightning.

Wildfires are not strictly a weather-related threat.  The weather does however play a significant role in starting fires and in the ability of firefighters to battle them.

From the National Weather Service:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
500 PM MDT SAT JUNE 26 2021

Colorado Lightning Safety Week concludes today…with wildfires being the final topic.

During the past week we have presented lightning information and safety rules.  Although wildfires are not an actual weather phenomenon…wildfires are directly related to lightning and other weather elements.

Normally…the wildfire threat in Colorado increases significantly after the middle of June and usually peaks in early July…and remains high through august and early September.  Colorado averages about 2500 wildfires each year.

About half of all forest fires in Colorado are ignited by lightning. Additionally…many rangeland and wheat field fires are caused by lightning. Many of these lightning caused wildfires occur in the absence of rain and are the result of what is referred to as dry thunderstorms.

Lightning is often accompanied by strong winds from thunderstorms. These winds can quickly turn smoldering organic material into a raging fire.  Thunderstorm winds tend to be erratic in direction and speed…posing one of the greatest dangers for firefighters.

Lightning that strikes the ground is usually divided into two categories…negative and positive strikes… Depending on the ionic source region of the thunderstorm.  The negative strikes are far more common than positive strikes.  The positive strikes are more intense and have a longer duration than the negative strikes and are more likely to ignite a fire.  Lightning detection technology provides land managers and weather forecasters with the ability to identify the general location and charge category of each lightning strike.

National Weather Service forecasters help land managers and firefighters by producing fire weather zone forecasts on a daily basis.  Spot fire weather forecasts are also provided for those who work on prescribed burns or specific wildfires.  Forecasters also issue red flag warnings for use by land managers when the combination of dry vegetation and critical weather conditions will result in a high potential for the development and spread of

Wildfires.  Land managers…in turn… Typically inform the general public of the fire danger in national parks…forests… And other public lands.

During periods of extreme fire danger in forests and rangelands…

  • You should avoid being in areas where you might become trapped by a wildfire.
  • You should avoid the use of matches or anything else which could ignite a fire.
  • Make sure that hot parts of motorized equipment…such as mufflers…are not allowed to come in contact with dry grasses or other potentially flammable material.
  • If you become trapped or cut off by a wildfire seek shelter in areas with little or no fuel…such as rock slide areas or lakes.

For more information on wildfires and fire safety…please check out the following web addresses…

Lightning Safety and Wildfire Awareness Series:

When lightning strikes – Rendering aid and the lasting effects of a strike

Lightning strike (NOAA)
Responding quickly to lightning strike victims is key to helping them survive. (NOAA)

Knowing what to do when lightning strikes someone is critical to helping them survive.  As with many serious injuries, immediate action must be taken.  After the event, lightning strike victims oftentimes face a number of health and mental challenges.

From the National Weather Service:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BOULDER CO
600 AM MDT FRI Jun 25 2021

Colorado Lightning Safety Awareness Week continues through tomorrow. Today we discuss lightning medical issues for survivors.

The facts about lightning strike victims:

In Colorado, nearly a half million cloud-to-ground lightning flashes are documented each year. With millions of visitors and extensive outdoor activities, it is not surprising that, each year on average, three people are killed by lightning in the state of Colorado while 13 are injured. Last year, two people were killed by lightning in the Centennial State while seven were injured.

While any lightning fatality is tragic, injuries caused by lightning can be devastating to both the victim and the family. For those who have a family member or relative that suffers a significant disability from lightning, life changes forever. In addition to the physical pain and mental anguish suffered by the victim and their family, the incident may lead to a loss of income for all involved as medical expenses can drain the family’s financial resources.

If someone is struck by lightning, it is critically important that they receive the appropriate medical attention immediately. Some deaths can be prevented if the victims are attended to promptly. Lightning victims do not carry an electrical charge and are safe to handle. First, check to see that the victim is breathing and has a pulse, and start cardio-pulmonary resuscitation, if needed. Then have someone dial 911. If possible, move the victim to a safer place. Do not let the rescuers become lightning victims. Lightning can strike the same place twice.

Lightning strike victims may face many mental challenges that they will have to live with for the rest of their lives. When the brain is affected by a lightning strike, the person often has difficulty with many of the mental processes that most people take for granted. The person may suffer from short-term memory loss, and may have difficulty remembering new information and accessing old information. Victims may often find it very difficult to carry on more than one task at a time, and may be easily distracted. Their personality may change and they may become easily irritated.

Lightning strike victims often become easily fatigued and may become exhausted after only a few hours of work. This may be because mental tasks that were once automatic may now require intense concentration to accomplish. Although some victims may sleep excessively at first, after a few weeks many find it difficult to sleep more than two or three hours at a time.

Another common long-term problem for survivors is pain.

Medically, pain is difficult to quantify. Lightning strike victims often suffer irreparable nerve damage that causes intense pain that affects the ability to function. Many survivors complain of chronic headaches, some of which are very intense and debilitating.

Lightning Strike and Electric Shock Survivors International is a support group for individuals and families that are struggling with life after a lightning injury. Helpful information is available at their web address: www.lightning-strike.org

In addition, NOAA’s lightning website contains abundant information on lightning safety and can be found at: www.lightningsafety.noaa.gov

Lightning information specific for the State of Colorado can be found at: www.weather.gov/pub/lightning

The lightning topic for tomorrow will be lightning caused fires.

Lightning Safety and Wildfire Awareness Series:

Weather, natural disasters & climate news and information.