Category Archives: Weather History

News and related items pertaining to national, Colorado, Denver and Thornton weather.

August 28 to September 3: This Week in Denver Weather History

This Week in Denver Weather History

So who is ready for some snow? Along with many other notable weather events, it was this week in Denver history when we received our earliest snowfall on record!

From the National Weather Service:

19-30

In 1875…grasshoppers appeared in great numbers at 10:00 am on the 19th. Thousands landed on the ground. The streets were literally covered with them. Swarms of grasshoppers were seen on each day. All gardens in the city were devastated…and in the countryside the grasshoppers were very destructive to ripened grain. On the 30th the grasshoppers were so numerous as to almost darken the sun.

27-28

In 2004…a brief chilly spell resulted in three temperature records. The high temperature of 55 degrees on the 27th was a record low maximum for the date. The low temperature of 48 degrees on the 27th equaled the record minimum for the date. The low temperature of 42 degrees on the 28th was a record minimum for the date.

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In 1887…a dry thunderstorm produced north winds to 48 mph but only a trace of rainfall.

In 1968…one man was seriously injured by lightning while riding on a roller coaster at a Denver amusement park. An airline employee was injured when lightning struck a jetliner he was servicing at Stapleton International Airport. A lightning-caused fire did extensive damage to one house and minor damage to several others in the city of Denver.

In 1970…a microburst wind gust to 53 mph was recorded at Stapleton International Airport.

In 2002…a severe thunderstorm produced 3/4 inch diameter hail near Parker.

In 2005…lightning sparked a small fire near Jamestown. The blaze was quickly contained and consumed less than an acre.

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In 1876…after the passage of a gentle rain shower to the east during the late evening hours…the moon shone brightly and a remarkably bright lunar rainbow appeared.

In 1910…an apparent cold front produced sustained northeast winds to 40 mph.

In 1946…the high temperature warmed to only 55 degrees…the record low maximum for the month.

In 1989…a spectacular lightning display knocked out power to 300 blocks in southeast Denver. One bolt started a fire in a lumber yard in the northeast part of the city…and the attic of a home in the same area was set ablaze by a lightning bolt.

In 1996…3/4 inch diameter hail was measured in Parker.

In 2000…lightning struck two homes in Thornton. The extent of damage was unknown.

In 2002…two small tornadoes caused damage in southeast metro Denver. The first tornado…associated with a multi-vortex storm…touched down briefly near E-470 and South Jordan Road. Some fences were damaged…and a few trees were blown down. A few of the homes also sustained minor roof damage. Damage from this storm totaled 100 thousand dollars. The second tornado associated with the storm touched down in a subdivision that was under construction at Gartrell and Arapahoe roads. Four large condominiums under construction were destroyed. The most heavily damaged portions of the structures were still in the framing stages. Adjacent sections where enclosed walls were in place were not destroyed. A man suffered 4 broken ribs and several cuts and bruises when the trailer he sought shelter in was flipped three times and torn apart by the twister. Damage from this storm totaled 6 million dollars. A severe thunderstorm produced 1 inch diameter hail near Evergreen.

In 2006…severe thunderstorms produced large hail in the foothills west of Denver. Hail to 1 inch in diameter fell near Blackhawk. Hail as large as 7/8 inch was measured near Idaho Springs…along with 3/4 inch hail near Nederland and conifer.

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In 1981…60 mph winds were reported in Boulder.

In 2004…a severe thunderstorm produced hail as large as 1 inch in diameter in south Aurora near Cherry Creek.

In 2016…an intense thunderstorm produced very heavy rain and hail in Westminster…where radar estimated up to 3.6 inches of rainfall. Several vehicles were stranded in 2 to 3 feet of moving water at the intersection of 72nd Ave. and Pecos St. Street flooding was also reported on U.S. 36 at Pecos St.

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In 1951…hail as large as 1 3/4 inches in diameter caused an estimated 300 thousand dollars damage in metro Denver. Hail as large as 1 1/2 inches in diameter was measured at Stapleton Airport.

In 1978…strong thunderstorm winds tore the roof off an apartment building in Aurora…downed trees…and damaged windows in Denver. A microburst wind gust to 58 mph was recorded at Stapleton International Airport.

In 1985…a thunderstorm wind gust to 60 mph was clocked at Buckley Field in Aurora.

In 1997…hail to 1 1/4 inches in diameter was measured in Aurora.

In 2006…a female postal worker was struck and injured by lightning while delivering mail in Westminster.

In 2008…lightning struck a home in Brighton…damaging the roof and a bedroom. The damaged totaled 20 thousand dollars.

In 2020…a worsening drought that started in the spring of 2020…continued through August. The month of August tied with 2011 for the warmest August on record. It also occurred in the middle of the second warmest summer on record. The combination of hot and dry conditions…in addition to critically dry fuels from years of beetle kill…resulted massive wildfires. The Cameron Peak fire…which became the largest wildfire in the state`s history started on August 13th and continued to burn into October. Smoke from this wildfire in addition to several other large wildfires in Colorado and the West resulted in multiple days of extremely poor air quality. In addition…the air quality in Denver and the entire Front Range had deteriorated severely due to the very warm temperatures and high ozone content… which had spiked significantly. In August…26 days in the month equaled or exceeded 90 degrees. Continue reading August 28 to September 3: This Week in Denver Weather History

August 21 to August 27: This week in Denver weather history

This Week in Denver Weather History

Denver’s weather is not often boring. Lightning, hail, tornadoes and even swarms of grasshoppers have made appearances this week in Denver weather history.

From the National Weather Service:

19-30

In 1875…grasshoppers appeared in great numbers at 10:00 am on the 19th. Thousands landed on the ground. The streets were literally covered with them. Swarms of grasshoppers were seen on each day. All gardens in the city were devastated…and in the countryside the grasshoppers were very destructive to ripened grain. On the 30th the grasshoppers were so numerous as to almost darken the sun.

21

In 1876…heavy thunderstorm rain and hail struck the city. Hail stones as large as partridge eggs accumulated to a depth of 1 1/2 feet over eastern portions of the city. The heavy rainfall flooded streets and gutters. However… No significant damage was reported. Rainfall totaled 0.85 inch in central Denver.

In 1903…a thunderstorm produced west winds sustained to 42 mph with gusts to 48 mph.

In 1957…heavy thunderstorm rainfall and hail over the bear creek basin flooded portions of State Highway 8 in and near Morrison. There was also minor property damage in Morrison.

In 1995…a 68-year-old woman was struck by lightning while standing near a tree in Brighton.

In 2006…a severe thunderstorm produced 7/8 inch diameter hail in Franktown.

In 2019…severe thunderstorms produced hail up to 1 inch in diameter in parts of Arapahoe…Denver and Jefferson counties. Heavy rain and flash flooding…close to 2 inches in one hour…also accompanied the nearly stationary storms. In Denver…flash flooding caused several vehicles to be stranded at Martin Luther King Blvd and Dahlia Street. Highway 6 near Federal Blvd also flooded. Standing water up to 3 feet deep occurred in Park Hill. Lastly…water made its way into buildings north of Interstate 70. At Denver International Airport…just a trace of rainfall was recorded.

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In 1898…an apparent thunderstorm produced southwest sustained winds to 40 mph with gusts to 43 mph.

In 1903…a late afternoon thunderstorm produced rain…hail… And east winds sustained to 40 mph with gusts to 44 mph.

In 1904…the lowest recorded temperature in August…40 degrees…occurred. The same temperature also occurred on three consecutive days…August 24…25…and 26 in 1910.

In 1965…heavy rain and hail caused some damage from flooding over northern Douglas County from Castle Rock to Franktown.

In 1981…thunderstorms moved across metro Denver. At least 5 funnel cloud sightings were reported. Funnel clouds were seen at 96th Ave. and Sheridan Blvd. And at 92nd Ave. and Federal Blvd. in Westminster and 7 miles north of Stapleton International Airport. Lightning injured two people in Boulder. A quarter inch of rain fell in just 5 minutes in Brighton. Up to 3/4 inch of rain doused Parker in 30 minutes.

In 1983…3/4 inch diameter hail was reported at Kittredge… Along with 0.60 inch of rain in 25 minutes.

In 1984…a thunderstorm dumped 4 inches of rain on Brighton in 90 minutes…causing extensive street flooding in the downtown area.

In 1987…over an inch of rain fell in 24 hours throughout most of metro Denver. A public library suffered water damage to the ceiling…carpet…and a few books. Rainfall was 0.76 inch at Stapleton International Airport.

In 1990…lightning knocked out power to about 2500 homes in Lakewood for about an hour.

In 1991…National Weather Service personnel at Stapleton International Airport sighted an apparent tornado briefly on the ground 3 miles west-northwest of the airport. No damage was reported.

In 1995…lightning struck 3 electrical power substations in Louisville. Residences of more than 4500 people were without power from 30 minutes to more than an hour.

In 1996…between 1 and 3 inches of rain fell across metro Denver. As a result…several low lying areas were flooded. A bicyclist was swept into a fast moving creek when he tried to cross a flooded bike path. The man was washed downstream about 15 feet before getting snagged by a tree stump. He and a man who tried to rescue him received minor injuries. The heavy rain caused numerous power outages…false fire alarms…and traffic accidents. In Lakewood…telephone service to around 60 thousand residents was knocked out when a switching center was flooded. Funnel clouds were sighted near Chatfield Reservoir and Highlands Ranch.

In 2000…lightning sparked a blaze which gutted a 10-unit apartment building in Highlands Ranch. Twenty-eight people were left homeless. Damage was estimated at 2 million dollars.

In 2007…severe thunderstorms produced large hail…up to 1 1/4 inches in diameter…in the vicinities of Castle Rock… Elizabeth and Franktown.

In 2013…flash flooding occurred in central Douglas County with numerous road closures reported. One of the closures occurred at the Tomah Road exit along I-25…south of Castle Rock.  The closure backed up all I-25 the way to Castle Rock. At Denver International Airport…1.94 inches of precipitation was recorded…which set a new record rainfall for the date. The old record was 0.75 inches… set back in 1953.

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In 1987…some locations in metro Denver had a total 3-day rainfall of 2 to 4 inches. Rainfall totaled 0.96 inch at Stapleton International Airport.

Continue reading August 21 to August 27: This week in Denver weather history

August 14 to August 20: This week in Denver weather history

This Week in Denver Weather History

Severe weather is a fact of life in Colorado during the summer months and while August is historically relatively calm, that isn’t always the case. In our look back at this week in Denver weather history we see the dangers of lightning, incidents of large hail and flooding rains and even a tornado.

From the National Weather Service:

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In 1960…a bolt of lightning struck a man in Henderson… Causing serious burns.

In 1962…the temperature climbed to a high of 100 degrees at Stapleton Airport.

In 1968…a young man on a golf course in Denver was injured when lightning struck a tree under which he was standing. Lightning caused minor damage to a house in Denver. Heavy thunderstorm rain caused local street flooding. One inch diameter hail fell at Jefferson County Airport near Broomfield.

In 1973…winds as high as 85 mph damaged 20 aircraft at the Arapahoe County airport…now centennial airport.

In 1977…three tornadoes were sighted in Bennett. A man suffered a broken leg when hit by a flying board. He was outside his camper home…which was destroyed. All windows were broken in a near-by farmhouse where some shingles were ripped off and a 2 car garage was knocked down. Several vehicles were damaged and a cat…some rabbits…and chickens were killed. A broken oar from a boat was driven into the side of a house. A mobile home was overturned. One old barn was destroyed. Half a dozen homes and several agricultural buildings were damaged just west of State Highway 79.

In 1978…high winds produced much blowing dust…causing many traffic accidents in the Denver-Boulder area. Winds gusts of 70 to 101 mph were recorded. Northwest winds gusted to 44 mph at Stapleton International Airport.

In 1980…lightning hit two power poles in Littleton…causing 400 dollars in damage. Rainfall of 1.23 inches in a short time caused minor flooding…which included damage to a ground floor apartment and partially submerging a few vehicles in water. Thunderstorm rainfall totaled 0.98 inch at Stapleton International Airport.

In 1983…2.10 inches of rain drenched Golden in an hour with similar amounts in Lakewood and Boulder. Over ten thousand dollars worth of plants were washed away at a nursery in Lakewood.

In 1997…twelve motorists were injured in a multi-car accident when strong microburst winds estimated to 50 mph blew blinding dust across I-70 near Bennett.

In 1998…lightning struck a hydro-electric plant in Nederland… Causing a power outage. Residents in the foothills west of Boulder…including Nederland…Ward…Eldora…Jamestown… And Gold Hill…were without power for about an hour.

In 2006…heavy thunderstorm rainfall near Deckers washed away some the banks along State Highway 67 between Deckers and Westcreek. Several driveways on both sides of the highway were also damaged.

15

In 1899…a thunderstorm produced southwest sustained winds to 43 mph with gusts to 46 mph.

In 1972…a pilot reported a funnel cloud briefly touching the ground in open fields…17 miles east-northeast of Stapleton International Airport.

In 1980…thunderstorm winds gusted to 55 mph in Boulder.

In 1982…brief heavy rain and winds estimated as high as 70 mph occurred in the conifer-Evergreen area. No damage was reported.

In 1990…lightning triggered a small attic fire in a house near Sedalia…20 miles south of Denver. A furious lightning storm caused widespread power outages across southern sections of metro Denver. One lightning bolt knocked out an electrical substation…causing a 90-minute blackout in southeast Denver affecting nearly 10 thousand homes and businesses.

In 2007…severe thunderstorms produced large hail…up to 2 inches in diameter…near larkspur. Extensive damage to vehicles in the area was reported.

In Parker…lightning struck a residence. The ensuing fire damaged the attic and top floor; causing $100000 in property damage.

In 2008…at least three homes were hit by lightning during the early morning hours in Arapahoe County. Lightning also struck two homes in Castle Rock…damaging the roofs.

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In 1902…a thunderstorm produced west winds sustained to 48 mph with gusts to 60 mph…but only a trace of rain.

In 1952…a thunderstorm wind gust to 50 mph was recorded at Stapleton Airport.

In 1960…lightning struck a warehouse in central Denver… Causing 8 thousand dollars in damage to the building and stored electrical equipment.

In 1975…large hail…1 1/2 to 1 3/4 inches in diameter…fell about 4 miles north of Castle Rock. Hail caused some minor damage in Aurora. A funnel cloud was reported 25 miles east of Denver near Bennett.

In 1981…a tornado touched down briefly in open country just to the east of Aurora. No damage was reported.

In 1982…a thunderstorm wind gust to 61 mph was recorded at Buckley Field in Aurora. At the same time almost an inch of rain flooded and closed streets in south Aurora. A women was hit by lightning just north of Denver. A house in the area was also struck.

In 1985…a thunderstorm produced strong wind gusts over southern metro Denver. One strong wind gust hit Cheery Creek Reservoir…capsizing a boat and drowning a man. The wind gusts…clocked as high as 50 mph…also downed a few trees.

In 1989…1 3/4 inch diameter hail fell at Intercanyon in the foothills of Jefferson County.

In 1990…lightning caused minor damage to a south Aurora home. No injuries were reported.

In 1994…strong thunderstorm winds caused damage in southern weld County near Hudson and Fort Lupton. Two mobile homes were destroyed and a few lost their roofs. Up to 20 downed power poles and the destruction of two 115 thousand-volt towers caused widespread power outages. Thunderstorm gust front winds from the north gusted to 48 mph at Stapleton International Airport.

In 2000…lightning ripped most of the roof from a home in southeast Aurora. The bolt sparked a fire which destroyed the residence. Damage was estimated at 250 thousand dollars.

In 2002…the temperature climbed to a maximum of 100 degrees setting a new record high for the date.

In 2003…a teenager was injured when he was struck by lightning while camping at Herman Lake…13 miles northwest of Georgetown. The boy was knocked unconscious and suffered minor injuries.

In 2013…a dry microburst uprooted 30 to 40 large trees across a 12-block area of the Park Hill neighborhood in east central Denver. Several trees were snapped near the base along with numerous branches…8 to 10 inches in diameter. Power poles and lines were also downed with resulted in outages which affected seven hundred residents. One of the downed trees crushed a car`s hood… narrowly missing the driver. At Denver International Airport…a peak wind gust of 22 mph was observed from the southwest. Continue reading August 14 to August 20: This week in Denver weather history

August 7 to August 13: This week in Denver weather history

This Week in Denver Weather History

As we get further into the month of August severe weather is less common. It can however still strike as we see in our look at this week in Denver weather history. Everything from torrential rains to massive hail and even a tornado have been reported.

From the National Weather Service:

7

In 1948…a brief west moving tornado was sighted 3 miles north-northeast of Stapleton Airport. The white funnel silhouetted against a gray cloud background was very narrow…nearly vertical…and estimated at nearly 5 thousand feet high. A dust cloud formed on the ground around the funnel. No damage was reported.

In 1952…a thunderstorm wind gust to 52 mph was recorded at Stapleton Airport.

In 2014…severe thunderstorms produced large hail across western and southern parts of metro Denver. Near Centennial and Golden…hail up to quarter size was reported. Near Bennett…a peak thunderstorm wind gust to 65 mph was also reported. At Denver International Airport…a peak wind gust to 46 mph was recorded.

In 2018…a severe thunderstorm produced large hail around Denver and vicinity. Hail ranging in size from 1 to 1 3/4
inches fell near Firestone…Ft Lupton…Parker…and Smoky Hill.

8

In 1874…swarms of grasshoppers invaded the city. Millions of them were seen cruising through the air. The insects were apparently picked up by a thunderstorm gust front and carried into the city. The grasshoppers had ravaged crops in surrounding counties for the last month.

In 1878…the highest temperature ever recorded in Denver…105 degrees…occurred at 3:20 pm. This temperature was equaled on July 20th in 2005.

In 1969…the temperature reached 100 degrees at Stapleton International Airport.

In 1976…in Thornton…a 13 year old boy riding a bicycle was struck and killed by lightning.

In 2000…lightning struck three homes in central Arapahoe County east of Denver. Damage was estimated at 47 thousand dollars.

In 2003…hail to 1 inch in diameter pelted Denver. Hail to 7/8 inch was measured in Boulder.

In 2008…heavy rain also caused flash flooding over south Denver and its nearby suburbs. Heavy rain…from 2.5 to 4 inches…fell in less than 90 minutes. Firefighters rescued 20 people as the water quickly rose along creeks…flooded roadways…and stranded motorists. Three people had to be rescued along Cherry Creek when the bike path flooded.

In Evergreen…a man suffered minor injuries when he was struck by lightning. It entered his finger…traveled down his body… And exited his foot.

In 2013…heavy rain caused localized flash flooding in Aurora. An undergound parking garage at an apartment complex was inundated with 3 to 4 feet of water. Flash flooding forced a road closure at East Mississippi Ave. and Alton St. Also… several people had to be rescued when three vehicles stalled in floodwaters at Alameda Ave. and Havana St. The stationary thunderstorms dumped 2.75 inches of rain in less than 45 minutes. In addition…large hail…up to one inch in diameter… was reported north of Roxbourough State Park. At Denver International Airport…just a trace of rainfall was observed.

8-10

In 1979…heavy thunderstorm rains on each of three consecutive days dumped a total of 2.22 inches of rain at Stapleton International Airport. The heaviest rain… 0.95 inches…fell on the 9th. Small hail to 1/8 inch diameter fell on the 8th.

8-13

In 1875…clouds of grasshoppers were seen flying through the air on the prevailing winds during each day.

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In 1900…a thunderstorm produced west winds sustained to 47 mph with gusts to 55 mph…but only 0.01 inch of rain.

In 1902…a thunderstorm produced no rain and north winds sustained to 52 mph with gusts to 60 mph.

In 1934…heavy cloudbursts in the foothills near Kittredge and at the head of Mount Vernon creek caused flash flooding on both Bear Creek and Mount Vernon Creek at Morrison… Which resulted in 6 deaths and much property damage. The highway in Mount Vernon canyon was destroyed by the flood waters.

In 1981…3/4 inch hail fell at Kittredge near Evergreen in Jefferson County.

In 1987…3/4 inch hail fell in Boulder and 9 miles northwest of Castle Rock.

In 1995…lightning struck a 16-year-old counselor in the back of the head while he and a friend were standing under a tree at the singing river ranch…7 miles west of Evergreen. He stopped breathing…but his friend was able to summon help and they were able to revive him. He was hospitalized for a few days and released.

In 1998…brief…weak tornadoes (f0) were sighted near Bennett and Roggen. No damage was reported. Hail as large as 1 inch diameter fell in Franktown with 3/4 inch diameter hail measured near Castle Rock. Thunderstorm winds gusted to 61 mph near Roggen.

9-10

In 2006…mid and high cloudiness overnight on both days resulted in two temperature records. The low temperature of 71 degrees on the 9th was a record high minimum for the date. The low temperature of 68 degrees on the 10th equaled the record high minimum for the date first set in 1936.

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In 1924…0.01 inch of rain fell over downtown Denver. This along with the 0.01 inch of rainfall on the 4th was the only rainfall of the month…making this the driest August on record in the city.

In 1962…the high temperature reached 100 degrees at Stapleton Airport.

In 1970…hail stones to 1 inch in diameter were reported in the Fort Lupton area.

In 1972…dry thunderstorm microburst winds gusting to 46 mph briefly reduced the surface visibility to 3/4 mile in blowing dust at Stapleton International Airport.

In 1978…lightning struck two men in Aurora…killing one and injuring the other.

In 1982…a tornado was sighted near Castle Rock and remained on the ground for 10 minutes. Wind gusts to 60 mph were reported in Castle Rock. No damage was reported.

In 1994…heavy thunderstorm rains caused flash flooding on Lena Gulch in west metro Denver. Damage was estimated at 50 thousand dollars. Lightning struck a house in Westminster…causing a small attic fire.

In 1996…strong thunderstorm winds toppled a tent at a company picnic in Westminster. Five people received minor injuries when the tent collapsed. Two cars nearby were also damaged by flying debris. A weak tornado (F0)…first sighted near Denver International Airport…traveled east to near Bennett and Strasburg. No significant damage was reported.

In 1998…heavy rain caused flooding and flash flooding problems over southwest metro Denver. An observer in Lakewood measured 3.26 inches of rainfall in an hour. Several streets were flooded in central Lakewood.

In addition…a trailer park along Lena Gulch in Wheat Ridge was evacuated due to high waters. One inch diameter hail fell near Roggen.

In 1999…thunderstorm-producing tornadoes…damaging straight line winds…heavy rain…and hail hammered metro Denver. In the city…small hail and heavy rainfall…up to 2.50 inches an hour…caused a 20-foot by 50-foot section of the roof to collapse at a furniture warehouse. Damage to the warehouse was estimated at 1 million dollars. Heavy rain also flooded several underpasses with up to 3 feet of water…which resulted in a number of stalled vehicles. In Fort Lupton…a tornado bounced across the area. Spotty damage was reported along a 5-mile path as trees…power poles…and lines were downed. In addition…an empty semi-trailer was overturned onto another vehicle northeast of the town. Thunderstorm winds gusted to 81 mph south of Fort Lupton.

In 2004…severe thunderstorms pummeled metro Denver with large hail. Hail up to 3 inches in diameter was measured 10 miles east of Castle Rock. Two inch diameter hail fell in Louisville…10 miles north of Hudson…and 1 mile east of Brighton. Hail to 1.75 inches was reported in Englewood… 1 mile south of Ft. Lupton…and 8 miles east of Boulder. Hail to 1.50 inches was reported around Boulder…near Broomfield…and in Lafayette…Thornton and greenwood village. Hail from 3/4 to 1 inch in diameter was found in Broomfield… Brighton…Castle Rock…Denver and Thornton…and near Longmont… Northglenn…greenwood village…Morrison…and Wheat Ridge. Severe thunderstorm wind gusts were recorded to 66 mph in Parker and to 60 mph 5 miles northeast of Boulder. There were no damage estimates from the hail or wind.

11 Continue reading August 7 to August 13: This week in Denver weather history

July 31 to August 6: This Week in Denver Weather History

This Week in Denver Weather History

How does 42 degrees sound right about now? That mark is one of the highlights of this week in Denver weather history. It was the low temperature recorded twice in our past and the coldest July temperature on record. Many more notable events have also occurred.

From the National Weather Service:

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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.

27-31

In 1956…96 percent of the total precipitation for the month of July occurred over the last five days of the month. Heavy thunderstorms produced 4.00 inches of rainfall at Stapleton Airport. This amount of precipitation in 5 days or less had been exceeded only 3 times in previous record. The last time had been in December of 1913 as snow. Considerable property damage occurred across metro Denver from flooding.

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In 1873…the all-time lowest recorded temperature in July… 42 degrees…occurred. The same temperature also occurred on July 4…1903.

In 1874…during the late afternoon rain and hail fell for 5 minutes followed by brief heavy rain. Pieces of solid ice of irregular shape fell upon the roof of the station. The hail stones measured 1 1/2 inches in diameter. Precipitation (rain and melted hail) was only 0.16 inch.

In 1889…the high temperature climbed to 100 degrees in downtown Denver.

In 1919…heavy thunderstorm rainfall totaled 2.59 inches in downtown Denver during the evening. Rainfall was 1.90 inches in an hour…a new record at that time.

In 1961…over an inch of rain in a short period of time caused flooding of streets and basements in Denver. Rainfall totaled 1.30 inches at 11th and Lincoln in central Denver.

In 1964…the temperature reached 91 degrees in Denver…making this the 27th day of the month that the temperature reached 90 degrees or more. This is the all time record for 90 degree days in a month in Denver.

In 1972…one inch diameter hail fell in Hudson northeast of Denver.

In 1976…during the evening hours extremely heavy thunderstorm rains produced flash flooding in Big Thompson Canyon which killed 144 people between Estes Park and Loveland. No significant weather occurred in metro Denver at the time.

In 1987…1 inch diameter hail fell in Lakewood and 3/4 inch hail fell near Louisville. Southeast Boulder County was drenched with 1.25 inches of rain in just 20 minutes.

In 1993…thunderstorm winds damaged a chimney of a home near Parker.

In 1996…a weak tornado (f0) was sighted 12 miles east of Denver International Airport. No damage was reported.

In 1998…heavy monsoonal thunderstorm rain triggered a mud slide in Blackhawk. The mudslide blocked Main St. and caused an estimated half million dollars in damage to a casino. Heavy thunderstorm rain…up to 3 inches in an hour…caused a flash flood along Buffalo Creek. Portions of County Road 126 just south of the town of Buffalo Creek were washed out. The flood waters nearly washed away the bridge as mud and debris slammed into the structure. Hail to 1 3/4 inches in diameter fell near Idaho Springs.

In 2004…severe thunderstorm winds toppled a 65-foot blue spruce tree in Parker. The tree landed on a home damaging the roof and gutters. The downed tree poked dozens of holes into the shingles.

In 2013…severe thunderstorm winds… with gusts estimated to 80 mph…downed power poles which caused scattered outages in and around Byers…Bennett and Strasburg. Some property damage was also observed. Near Byers…aluminum siding and roofing was peeled off sheds. Large hail…up to one inch in diameter… was reported north of Bennett. At Denver International Airport…a peak wind gust to 40 mph was observed from the northeast.

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In 1888…heavy rain in the mountains and foothills caused flooding on clear creek in Golden. The high waters also washed away portions of the railroad tracks in the canyon between Idaho Springs and Golden.

In 1901…the temperature reached a high of 100 degrees in the city.

In 1902…the high temperature climbed to 100 degrees in downtown Denver.

In 1914…a thunderstorm produced 1.00 inch of rainfall in just 21 minutes and north winds sustained at 43 mph with gusts to 50 mph. Rainfall totaled 1.17 inches.

In 1938…the temperature climbed to a high of 100 degrees in downtown Denver…which is the record maximum for the date. The temperature was also recorded on this date in previous years.

In 1976…flight operations at Stapleton International Airport were suspended for 90 minutes when the airport tower radar was knocked out and water reached a foot deep on some taxi ramps after 1.50 inches of rain fell in one hour. Heavy rain also caused minor flooding in east Denver and Aurora where lightning damaged the roof of a home and injured the owner. One young man was swept down a flooded ditch…but was rescued by firemen. A number of rafts were floated in flooded streets. Thunderstorm rainfall totaled 1.71 inches at Stapleton International Airport.

In 1978…a tornado damaged a house and broke a power pole 5 miles northwest of Parker. A microburst wind gust to 52 mph briefly reduced visibility to 1 mile in blowing dust at Stapleton International Airport.

In 1985…heavy thunderstorms roared through the southern and western sections of metro Denver…producing large hail and heavy rain. Lightning hit a recreational vehicle trailer causing it to burn. There was a lot of street flooding over western suburbs where rainfall totaled over 2 inches in some areas. One inch diameter hail was reported in Littleton and near Evergreen. Hail piled 4 to 6 inches deep at Tinytown in the foothills southwest of Denver.

In 1990…a small rope-like tornado was spotted in open country 15 miles southeast of centennial airport. No damage was reported from the twister.

In 1992…pilots reported a funnel cloud near the construction site of the new Denver International Airport. A few minutes later…a tornado was reported near Bennett. The tornado remained on the ground for about 18 minutes and was visible from the national weather service office at Stapleton International Airport. Thunderstorm wind gusts to 70 mph were reported near Bennett and Watkins with a wind gust to 60 mph at Brighton. Two men were injured when struck by lightning. A young man sustained serious injuries when struck by lightning while jet skiing on Cheery Creek Reservoir. A man received only minor injuries when struck by lightning while golfing in Westminster.

In 1994…heavy thunderstorm rains in the foothills west of Denver caused the closure of the Virginia Canyon Road north of Idaho Springs by rocks and debris.

In 2001…a 34 year old man on the South Platte River bike path in Denver received minor injuries when lightning struck a nearby tree. Lightning…coupled with strong thunderstorm winds…knocked out electrical power to about 10 thousand homes and businesses in Golden.

In 2006…strong thunderstorms hit southern metro Denver. A severe thunderstorm wind gust estimated to 71 mph knocked down a tree in Aurora near Cherry Creek. Lightning sparked a fire in a home near lone tree and struck a transformer at an RTD light rail station at Interstate 25 and Yosemite Street. Heavy thunderstorm rainfall forced the closure of Arapahoe Road between Holly and Quebec streets due to high water. Flooding was also reported near Park Meadows Mall and Greenwood Village. Heavy rainfall also caused flooding in Highlands Ranch…lone tree…and Parker. Water up to 6 inches deep was reportedly running over the roads.

In 2020…a worsening drought that started in the spring of 2020…continued through August. The month of August tied with 2011 for the warmest August on record. It also occurred in the middle of the second warmest summer on record. The combination of hot and dry conditions…in addition to critically dry fuels from years of beetle kill…resulted massive wildfires. The Cameron Peak fire…which became the largest wildfire in the state`s history started on August 13th and continued to burn into October. Smoke from this wildfire in addition to several other large wildfires in Colorado and the West resulted in multiple days of extremely poor air quality. In addition…the air quality in Denver and the entire Front Range had deteriorated severely due to the very warm temperatures and high ozone content… which had spiked significantly. In August…26 days in the month equaled or exceeded 90 degrees.

Continue reading July 31 to August 6: This Week in Denver Weather History

July 24 to July 30: This week in Denver weather history

This Week in Denver Weather History

As we near the end of July the weather in Denver tends to be a bit more stable. That doesn’t mean the severe weather threat disappears as can be seen at our look back at this week in Denver weather history. Particularly notable are lightning injuries and deaths, flash flood events and even tornadoes.

From the National Weather Service:

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.

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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.

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.

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In 1896…heavy cloudbursts in the foothills west of Denver caused flash flooding on Bear Creek…Clear Creek…Golden Gate Gulch…and Mount Vernon Creek…resulting in a total of 27 deaths. The downpour dislodged large Boulders…one of which crushed a house. The heavy rain also caused a dam on cub creek to wash out…adding even more water to the flood. A wall of water as high as 10 feet flooded Evergreen and passed down bear creek…washing away many structures along the way. The flood crest produced 3 feet of water in downtown Morrison during the early evening. Flash flooding on Mount Vernon Creek added to the flooding in Morrison. In Golden…the flooding washed out bridges on clear creek and on Cresman and Tucker gulches and forced the closure of the power plant. In Denver…a thunderstorm produced hail of unknown size during the afternoon and rainfall of 1.23 inches overnight.

In 1958…a thunderstorm wind gust to 52 mph was recorded at Stapleton Airport.

In 1965…heavy rain caused flooding on clear creek and tucker gulch in Golden and west Denver. Damage in Golden was estimated at 80 thousand dollars. Heavy rain south of Denver washed out temporary earthen bridges constructed following the June floods in Castle Rock…Littleton… Englewood…and Denver. Bear creek in south Denver reached flood stage. A cloudburst on cub creek in Evergreen washed out bridges and roads. Heavy rain fell over all the Denver and Aurora areas…causing some flooding of roads…streets… And bridges. A man drowned in a flooded irrigation canal near Hudson. Heavy rain caused flooding of streets and roads in Blackhawk and central city. Hail caused minor damage in Idaho Springs.

In 1967…seven bridges were washed out along a normally dry creek bed south of State Highway 7 west of Brighton. One car was washed into the creek when a bridge gave way.

In 1970…hail stones to 1 1/4 inches in diameter fell in the foothills of Jefferson County southwest of Denver.

In 1971…golf ball size hail was reported in foothill areas of Jefferson County west of Denver. A funnel cloud was sighted in Aurora. Wind gusts estimated at 60 mph…hail… And heavy rain up to an inch in 15 minutes caused local flooding and some other damage in several areas of metro Denver. Hailstones to 3/4 inch in diameter fell 7 miles southeast of Denver.

In 1973…a thunderstorm wind gust to 52 mph was recorded at Stapleton International Airport where one inch diameter hail was measured.

In 1981…strong winds downed a power line in northeast Denver. Wind gusts to 50 mph were recorded at Chatfield Reservoir.

In 1987…3/4 inch diameter hail fell 5 miles northeast of Commerce City.

In 1996…hail…up to 1 3/4 inches in diameter…fell at Chatfield Reservoir. Hail to 3/4 inch in diameter was measured near Bennett.

In 2000…lightning struck near two golfers at ute creek golf course near Longmont…knocking them to the ground. The men received only minor injuries.

In 2001…lightning from a thunderstorm knocked out electrical power to about 1500 residents in the city of Denver.

In 2004…a chilly day with fog and thunderstorms resulted in two temperature records. The low temperature of 49 degrees was a record minimum for the date. The high temperature of only 58 degrees was a record low maximum for the date.

In 2016…severe thunderstorms produced damaging straight-line. A storm leveled a greenhouse and caused tree damage near Byers. A peak wind gust to 74 mph was measured at Denver International Airport.

In 2018…thunderstorms produced very heavy rainfall…1 to 2 inches in less than 30 minutes. In Englewood…the floodwaters quickly inundated a basement apartment and trapped a woman inside. She was found unresponsive in the apartment and died several hours later. Several homes in the immediate area suffered severe flood damage. The floodwaters also stalled vehicles and forced the closure of several intersections. In Sheridan…the heavy rain created a large sinkhole which swallowed a small SUV. A downed power line caused a fire in Arapahoe County.

24-25 Continue reading July 24 to July 30: This week in Denver weather history

July 17 to July 23: This Week in Denver Weather History

This Week in Denver Weather History

Our weekly look back at Denver weather history always has interesting items but this week one stands out in particular. Denver has never officially recorded snow during the month of July. However, before official records began in 1882, the U.S. Army Signal Service weather observer reported snow on July 17, 1872!

From the National Weather Service:

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.

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.

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In 1872…the U.S. Army Signal Service weather observer recorded snowfall during the early morning hours in the hand written daily weather journal: “rain commenced at 1:30 a.m. changing about 3 a.m. to snow & in about half an hour to rain again; it continued until 6 a.m.” this is the only recorded occurrence of snowfall in Denver in July…but this report is not included in the “official” station snowfall records…which did not begin in Denver until January 1…1882. The low temperature on this morning was 45 degrees…which is sufficiently cold for the occurrence of light stratiform snowfall.

In 1918…a thunderstorm produced hail to an inch in depth on the ground. The stones varied in size from a small cherry stone to nearly 1/2 inch in diameter. Not much permanent damage was done to crops. Precipitation totaled 0.40 inch…and northeast winds were sustained to 25 mph with gusts to 28 mph.

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

In 1983…3/4 inch diameter hail fell at Lafayette…while golf ball size hail pelted Brighton and Northglenn where funnel clouds were also sighted.

In 1986…1 1/2 inches of rain fell in an hour and 15 minutes in southeastern Aurora. Thunderstorm rainfall totaled 0.89 inches at Stapleton International Airport.

In 1987…a small tornado was sighted near Watkins…in the vicinity of Front Range airport.

In 1997…lightning ignited an oil well tank holding 10 thousand gallons of oil…16 miles northwest of Bennett. About 200 acres of grassland burned before the fire could be extinguished. A dry microburst produced a wind gust to 52 mph at Denver International Airport.

In 2000…an estimated 2 inches of rain fell in less than an hour…causing two secondary roads in buck and miller gulches in the hi meadows fire burn area to wash out. Water also covered Jefferson County road 68 which connects to Bailey. Homeowners in pine valley estates attempted to divert some of the runoff by piling stacks of hay on the hillside above their homes. Torrential rainfall…up to 3.50 inches an hour…caused flash flooding along Whiskey Gulch near Elizabeth. Several roads were washed out and basements flooded during the storm. Along County Road 13… About 6 miles north-northwest of Elizabeth…rushing water washed away a 15-foot section of the road. The floodwaters forced debris and mud into four huge culverts…sending water over the road. At Denver International Airport…an United Airlines ground crew worker was struck by lightning as she was loading a Boeing 747 jumbo jet. The woman was injured when lightning either hit the jet or the loading equipment that she was working near. The 25-year-old woman received only minor injuries.

In 2006…outflow from severe thunderstorms to the southeast of metro Denver produced southeast sustained winds to 35 mph with gusts as high as 52 mph at Denver International Airport during the late evening.

In 2011…a deluge of heavy rain occurred in and around Nederland when the storm dumped nearly 2 inches of rain in 30 minutes. The heavy rainfall washed out hillsides and dirt roads. In Nederland…a culvert became blocked with debris and forced the water to spread into a nearby bookstore. The rainfall also damaged several residential roads in the Sunnyside Subdivision and Navajo Road became impassable. Several homes suffered flood damage as the runoff from a nearby Beaver Creek jumped its banks and flooded garages…living rooms and bedrooms of nearby houses.

In 2016…a severe thunderstorm produced hail up to 1 inch in diameter near Buckley Air Force Base.

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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.

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.
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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.

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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.

20 Continue reading July 17 to July 23: This Week in Denver Weather History

July 10 to July 16: This Week in Denver Weather History

This Week in Denver Weather History

Our look back at this week in Denver weather history demonstrates why July is considered the Mile High City’s stormiest month. Many instances of flooding rains, damaging wind and hail and dangerous lightning are seen in our past.

From the National Weather Service:

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.

9-10

In 1980…a series of severe thunderstorms hit metro Denver… Dumping heavy rain and producing a spectacular lightning display lasting for several hours. A number of homes were damaged by lightning. Winds gusted to 60 mph at Stapleton International Airport where about half an inch of rain fell in just 10 minutes along with 1/4 inch diameter hail. The evening thunderstorms continued into the early morning hours with total rainfall of 1.35 inches at Stapleton International Airport.

In 1998…thunderstorm rainfall totaled 2.04 inches at the site of the former Stapleton International Airport.

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In 1878…a lunar rainbow was observed during a light mist and fog.

In 1895…the temperature warmed to a high of only 53 degrees… The all-time record lowest maximum temperature for the month of July.

In 1967…golf ball size hail damaged aircraft at Jefferson County Airport near Broomfield.

In 1983…two people were injured when struck by lightning just southwest of Morrison. A man was injured when he was swept downstream by a flash flood on a tributary of clear creek in the canyon 8 miles west of Golden. Heavy thunderstorm rains caused mudslides which closed several roads. Rainfall amounts included: 1.75 inches in 20 minutes in southeast Denver…1.26 inches in 35 minutes in Boulder…2.14 inches in 2 hours in Lakewood…1.70 inches in 45 minutes in Aurora…and 1.25 inches in 30 minutes atop Floyd Hill in the foothills west of Denver.

In 1992…storm spotters reported 3/4 inch diameter hail near the construction site of the new Denver airport just northeast of the city.

In 1995…microburst winds toppled a pine tree 60 feet high and 2 feet in diameter in Denver. The tree fell and injured a man nearby. Microburst winds to 59 mph broke the glass on a door at the national weather service forecast office at the site of the former Stapleton International Airport.

In 1998…thunderstorm rainfall totaled 2.35 inches at Denver International Airport.

In 2000…three children were injured…one critically…when lightning hit a nearby tree at panorama point atop Flagstaff Mountain just west of Boulder. Lightning hit the tree…entered the ground…then struck the children. Lightning sparked a grassfire that burned about 50 acres at the Rocky Flats Environmental Test Facility. Also… Lightning sparked at least 6 fires in the Hudson and Keenesburg areas as thunderstorms…accompanied with heavy rain…large hail…and tornadoes…moved through southern Weld County. Over 2 inches of very heavy rain caused flooding along an I-76 exit ramp near Keenesburg. The fire department rescued 15 stranded motorists as high water inundated sections of the exit ramp and adjacent highway. Basements were also flooded in Keenesburg. One home reportedly had 7 feet of standing water in the basement before the rain subsided. A weak tornado (F0) touched down briefly near Brighton…but caused no damage.

In 2001…a severe thunderstorm dumped 7/8 inch diameter hail in wheat ridge.

In 2002…severe thunderstorms pelted the southern suburbs of metro Denver with large hail. Hail as large as 3 inches in diameter fell 6 miles southeast of Parker. Other large hail reports included 2 inch diameter hail around centennial airport and 3/4 inch hail near Sedalia and Deckers. Hail as large as 3/4 inch was also reported in Broomfield. Runoff from heavy thunderstorm rainfall in the Hayman fire burn area flooded lost creek ranch with up to 18 inches of water just off State Highway 126. Floodwaters damaged a very expensive rug in the lodge. A driveway to a residence was washed away. In Douglas County…runoff damaged forest access roads in the Turkey Creek drainage.

In 2011…a severe thunderstorm produced intense microburst winds in southeast Boulder County. A peak wind gust to 75 mph was recorded in Superior with gust to 58 mph…2 miles south of Lafayette. At Denver International Airport…a peak wind gust of 31 mph was recorded.

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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 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.

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.

Continue reading July 10 to July 16: This Week in Denver Weather History

July 3 to July 9: This Week in Denver Weather History

This Week in Denver Weather History

In our July weather preview we discussed how the month is not only Denver’s hottest but also its stormiest. Our look back at this week in Denver weather history helps to illustrate that fact. We start seeing 100+ degree days as well as many of the types of fast moving thunderstorm events expected this time of year.

From the National Weather Service:

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.

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In 1874…the temperature climbed to a high of 101 degrees in downtown Denver.

In 1881…the all time highest recorded daily minimum temperature of 77 degrees occurred in the city. This was also the highest daily minimum temperature ever recorded in July.

In 1885…a severe thunderstorm produced hail the size of hazel nuts…which fell with great force. A telegraph pole in west Denver was struck by lightning and shattered to pieces.

In 1955…a brief microburst wind gust to 61 mph was recorded at Stapleton Airport.

In 1960…a major hail storm caused 1.5 million dollars in damage across metro Denver. The heaviest damage occurred in south Denver…Englewood…Littleton…and Golden from wind- driven hail as large as golf balls and heavy rain which caused flooding. Winds were estimated at 60 to 70 mph. Rainfall was estimated at 2 to 3 inches. Hail accumulated 3 to 4 inches deep in some sections. Hail carried by flood waters drifted 3 to 4 feet deep. An Englewood policeman was injured when hail broke the windshield of his car. One inch of rain in 10 minutes…and heavy hail damage were reported in Parker. At some places the hail from the storm was still on the ground the next morning.

In 1967…large hail stones from 1 3/4 to 2 1/2 inches in diameter damaged cars and buildings in southwest Denver and Littleton where hail drifted to depths of 3 to 4 feet. The hail caused a great deal of damage…and streets were flooded by heavy rain over many sections of west metro Denver. At centennial race track near Littleton…a few hail stones were as large as tennis balls. Large hail broke the windshield on a Littleton police car. Golf ball to tennis ball size hail fell in the vicinity of Arapahoe road and south Broadway. One inch diameter hail fell at the intersection of orchard and south university. Golf ball size hail fell in Broomfield. Hail in Westminster was measured from 1 to 1 1/4 inches in diameter. Tornadoes were sighted by the public near Cheery Creek Reservoir… north of Commerce City…and in Arvada…but caused no reportable damage.

In 1993…high winds developed behind a strong cold front along portions of the Front Range. While the strongest winds were reported north of metro Denver…the winds blew out a half inch thick pane of glass from a vacant 9-story building. The glass landed on a parked car below. West winds gusting to 52 mph kicked up some blowing dust at Stapleton International Airport.

In 1996…lightning sparked a small fire near buffalo creek in southern Jefferson County. Only one acre burned before the fire was contained.

In 2002…heavy thunderstorm rain washed out a frontage road 6 miles north of Larkspur. The nearby mountain ranch subdivision was also flooded. Heavy rainfall in the Hayman fire burn area washed out a secondary road when debris from the runoff blocked a culvert. Hail as large as 3/4 inch fell near Keenesburg…in Castle Rock…and 7 miles to the south of Castle Rock.

In 2005…severe thunderstorms produced high winds. Wind gusts to 75 mph were measured near Longmont and to 60 mph just west of Boulder. No damage was reported.

In 2007…severe thunderstorms produced large hail in the foothills and suburbs west of Denver. Large hail from 1 to 2 inches in diameter was reported in the vicinity of Idaho Springs…Rollins and Edgewater.

In 2009…severe thunderstorms produced large hail and north and east of Denver. Hail up to one inch in diameter was observed near Erie and firestone. Hail up to 1 3/4 inches was observed 5 to 6 miles west-southwest of Byers. The golfball size hail caused extensive damage to a wheat field. In Aurora…six children received minor injuries when lightning struck a nearby tree. The injuries occurred when they were knocked down by the blast. None of the children suffered burns or appeared to have been directly hit by lightning.

In 2014…a severe thunderstorm produced large… up to 1 ½ inches in diameter…about 14 miles northwest of Golden.

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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.

In 2019…severe thunderstorms brought a wave of large hail across portions of Arapahoe…Broomfield…Denver…Douglas…Jefferson… and Weld counties. The hail ranged in size from 1 to 2 inches in diameter. The city of Lone Tree evacuated Sweetwater Park… where Fourth of July celebrations were underway…and Brighton delayed its Fourth of July concert. The Denver Outlaws game was postponed due to lightning. In Denver County…there was widespread damage from the hail…including damage to roof coverings and vehicles.

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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.

5 Continue reading July 3 to July 9: This Week in Denver Weather History

June 26 to July 2: This Week in Denver Weather History

This Week in Denver Weather History

Our look back at this week in Denver weather history certainly has plenty of the usual suspects related to severe weather. Most notable however are the many occurrences of lightning strikes and the effects they can have from sparking fires to causing significant injury and death.

From the National Weather Service:

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In 2012…from the 22nd to the 26th…the maximum temperature exceeded 100 degrees for five consecutive days.  Two of the high temperatures on the 25th and 26th 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 1969…high winds raked Boulder causing one fatality and some injuries. One man was injured by a falling tree limb. At the National Center for Atmospheric Research in Boulder… Sustained winds of 55 to 60 mph with wind gusts to 123 mph were recorded. In downtown Boulder…winds averaged 30 to 40 mph with gusts to 70 mph. Widespread minor damage occurred… Especially in the Table Mesa area of south Boulder. Much tree damage occurred in the older areas of Boulder where several trees were uprooted. A mobile home was overturned by the winds. At Stapleton Airport…west winds gusted to 43 mph on the 25th and 37 mph on the 26th.

In 1975…strong winds damaged utility lines…buildings… vehicles…trees…and power lines in Boulder and other communities to the north of Boulder. Microburst winds gusted to 45 mph at Stapleton International Airport on the 25th.

In 1983…heavy rain fell in the foothills west of Denver with 1.50 inches in 30 minutes at Intercanyon. Heavy rain continued over metro Denver on the 26th with two-day storm totals at many locations ranging from 1.00 to 2.50 inches. Rainfall totaled 1.37 inches at Stapleton International Airport on the 26th.

In 1985…one to two inches of rain fell over metro Denver. At Stapleton International Airport…rainfall totaled 0.93 inches…thunderstorm winds gusted to 44 mph…and 7/10 inch hail was measured. The air mass was unusually cold for the season…and snow fell in the foothills above 8 thousand feet. The high temperature of only 63 degrees on the 26th equaled the record low maximum reading for the date.

In 2012…Denver broke the all-time record temperature for the month of June on the 25th when it reached 105 degrees. This also tied the all-time record maximum temperature in Denver. The maximum temperature of 105 degrees was then matched once more on the 26th. Sandwiched in between these records…the minimum temperature of 71 on the morning of the 26th… established a new record high minimum for the date.

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In 1873…there was a great deal of smoke from a large forest fire in the mountains to the southwest of the city and a smaller fire directly to the west.

In 1874…fires at timberline to the west were visible from the city. New and extensive fires were continually started from south to northwest along the ridge line. Carelessness of tourists was the apparent cause of the fires. Large and valuable tracts of timber had already been destroyed.

In 1890…the only thunderstorm of the month produced a trace of rain. A trace of rain also fell on 7 other days. This was the only precipitation recorded during the month… Making it the driest June on record.

In 1893…northwest winds were sustained to 45 mph with gusts to 48 mph.

In 1971…a microburst wind gust to 58 mph was recorded at Stapleton International Airport. Dust devils were sighted.

In 1980…strong gusty thunderstorm winds damaged several mobile homes in Thornton. Thunderstorm winds gusted to 37 mph at Stapleton International Airport.

In 1986…hail piled up 1 1/2 inches deep in Golden Gate Canyon and covered roadways an inch deep in Evergreen.

In 1988…a tornado touched down 2 miles north of Watkins. It was on the ground for 15 minutes and did no reported damage.

In 1989…two inch diameter hail fell at Kassler…1 inch hail at Louviers…and 1 1/2 inch hail at tiny town.

In 1991…high winds…not associated with thunderstorms… Damaged a home in the Green Mountain area. The strong winds picked up a heavy metal and glass table on the deck of a house and threw it into the house. The table was destroyed and the house received considerable damage.

In 1992…3/4 inch diameter hail fell in south Aurora and near Buckley Air National Guard base. Golf ball size hail was reported in Parker.

In 1994…the all-time highest recorded temperature in June and the second highest temperature ever recorded in Denver… 104 degrees occurred. This was the hottest day in Denver since August 8…1878…when the temperature reached 105 degrees.

In 2005…strong thunderstorm winds gusting to 58 mph damaged a garage and some nearby trees near Fort Lupton. Winds also gusted to 58 mph near Watkins. Thunderstorm winds gusted to 60 mph near Roggen. Hail to 3/4 inch in diameter was measured in southwest Aurora.

In 2009…severe thunderstorms moving through Denver and the surrounding metro area produced intense thunderstorm winds. At Denver International Airport…a wind gust blew a luggage car into a southwest airlines airplane causing some damage. Peak wind gusts included: 68 mph at Denver International Airport…4 miles west of rocky mountain metropolitan airport and 12.5 miles north of Lowry AFB; 64 mph near Arvada and Parker; and 60 mph in Aurora/cherry.

In 2014…a severe thunderstorm produced a peak wind gust to 58 mph…9 miles northeast of Denver International Airport. Offically…a peak wind gust to 54 mph was measured from the northeast with just a trace of rainfall.

In 2020…severe thunderstorms produced very strong wind gusts over parts of northern Jefferson and western Adams counties.  A peak wind gust to 67 mph was observed at Rocky Mountain Metropolitan Airport near Broomfield…with a gust to 61 mph in Thornton.

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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.

Continue reading June 26 to July 2: This Week in Denver Weather History