Denver’s weather calms considerably in August as compared to many other months but the history books show plenty of notable events in our past. Lightning, flooding rain and even a tornado highlight this week in Denver weather history.

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

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In 1876…the temperature climbed to a high of 100 degrees in downtown Denver.

In 1941…excessive thunderstorm rainfall flooded streets and delayed traffic for a few hours in some sections of the city. The basements of a considerable number of homes and commercial buildings were flooded. The total value of the damage was unknown. Only 0.94 inch of thunderstorm rainfall was recorded downtown.

In 1969…a man and a 9-year old boy were injured…when lightning struck a tree near where they were standing. Both were revived after treatment…but the boy later died of respiratory failure due to electrical shock.

In 1984…heavy thunderstorm rains drenched southern metro Denver. Rural roads in Douglas County received minor washouts. Hail…as large as 3/4 inch in diameter…was reported in southeast Aurora with one inch diameter hail reported near Parker. Rainfall totaled 1.00 inch at Stapleton International Airport.
12-13 in 1975…heavy rains caused flash flooding along the foothills from Denver north. Thunderstorm rainfall totaled 1.56 inches at Stapleton International Airport.

In 2004…a brief cool spell resulted in two daily temperature records. The low temperature of 49 degrees was a record minimum for the 12th…as was the low temperature of 48 degrees on the 13th.

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In 1959…thunderstorm winds gusted to 53 mph at Stapleton Airport.

In 1983…thunderstorms dumped torrential rain in Northglenn… Thornton…and Broomfield. Northglenn was drenched with 1.72 inches in 30 minutes. Street flooding was widespread. Hail…as large as 3/4 inch in diameter…was reported 7 miles northeast of Boulder along with heavy rain which caused some street flooding.

In 2000…lightning sparked 3 small grass fires near Golden. The fires were quickly contained. Hail as large as 3/4 inch in diameter fell in Castle Rock.

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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.

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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 woman 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.

16-19

In 1979…heavy thunderstorm rains on each of 4 consecutive days dumped a total of 2.62 inches of rain on Stapleton International Airport. The heaviest rain…1.05 inches… On the 19th was accompanied by 1/4 inch diameter hail.

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In 1953…a tornado was sighted 8 miles east of Castle Rock. An unconfirmed tornado was sighted between Denver and Strasburg. No damage was reported.

In 1963…heavy rain in southeast Denver…Englewood…and Littleton caused flooding of basements and streets. Over 3.00 inches of rain fell at Cherry Creek dam. Lightning caused power failures. The hardest hit areas were in north- central Denver. A 12-year-old boy was swept into a conduit by a 3-foot high crest of water. He was carried 125 feet through the waterway…but was unhurt. Thunderstorm rainfall totaled only 0.24 inch at Stapleton Airport.

In 1972…a thunderstorm wind gust to 53 mph was recorded at Stapleton International Airport. Strong winds also occurred in the Littleton area where several trees and utility poles were blown over and a number of windows broken.

In 1978…1 3/4 inch diameter hail was reported in Thornton.

In 1982…heavy rain occurred in the foothills southwest of Denver where 4.50 inches fell in 75 minutes between Evergreen and Conifer. Nearby…2.66 inches of rain drenched the north turkey creek canyon area in just 15 minutes.

In 1984…scattered slow moving thunderstorms dumped heavy rain across southern metro Denver. The heavy rain caused some road washouts in Jefferson and Douglas counties. A bridge was washed out in Douglas County. Three inches of rain fell in just an hour at Castle Rock…causing heavy silt damage to a home and to nearby drainage ditches.

In 1988…a thunderstorm dumped 2 to 3 inches of rain in southeast Denver and adjacent areas of Arapahoe County in less than 90 minutes. There was widespread street flooding…and I-25 was closed by 4 feet of water near its intersection with I-225 just south of Denver. A flood control project in Arapahoe County at Greenwood Village sustained over 10 thousand dollars damage. Up to 4 feet of water flooded some basements in the area. Only 0.44 inch of rain fell at Stapleton International Airport.

In 1990…heavy thunderstorm rains over the Boulder Creek and St. Vrain creek drainage basins caused many creeks and drainage ditches to rise in eastern Boulder and southwest weld counties. The high waters punched three 30-foot holes in the embankment of a drainage ditch…which traversed through the town of firestone…20 miles north of Denver. A sheet of water 2 to 3 feet deep rushed out onto the streets of Firestone…forcing the evacuation of a trailer park and residents from 50 neighboring homes. No injuries or serious damage occurred except for mud and water damage. Lightning struck and injured 4 construction workers standing in an Aurora field. They received treatment for minor injuries at a local hospital. Lightning also struck the roof of a Methodist church in central Denver… Knocking down the highest peak of the steeple. A half dozen people were in the building…but no one was injured. Slow moving thunderstorms dumped 2 to 3 inches of rain over southeast Aurora in 90 minutes. The heavy rain accumulated on the roof of a condominium clubhouse…causing the roof to collapse under the weight of the water. Nearly 300 residents were evacuated from the 200-unit complex because of the structural damage. The residents were allowed to return to their homes when it was determined the damage was confined to the clubhouse. No injuries were reported.

In 1993…just west of Fort Lupton…thunderstorm winds blew the tin roof off a cattle shelter into a mobile home… Causing considerable damage to the mobile home.

In 1997…lightning struck a home in Castle Rock sparking a fire. Damage was estimated at 20 thousand dollars.

In 2000…thunderstorms producing very heavy rain…up to 3.50 inches in spots…caused flooding and flash flooding across metro Denver. In Commerce City…a 37-year-old firefighter drowned while attempting to rescue a stranded motorist on a flooded street. The firefighter was wading through the water when he lost his footing and was sucked into a 10 foot deep culvert. He was swept away before anyone could reach him. Extensive flooding was also reported throughout Littleton and north Denver.

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In 1965…heavy rain in areas south and east of Denver caused some flooding in Littleton and Englewood. Clear creek was running near bankfull…and heavy rain in southwest Denver flooded intersections.

In 1966…a brief very heavy thunderstorm dumped 0.61 inch of rain in just 5 minutes at Stapleton International Airport. Total rainfall from the storm…0.64 inch…fell in just 10 minutes. Half inch diameter hail also fell at Stapleton International Airport. The public sighted funnel clouds 10 to 15 miles south of the airport.

In 1967…hail struck in a strip along the eastern foothills and caused minor damage in Boulder. Hail accumulated to a depth of 4 to 6 inches in Jefferson County just southwest of Denver.

In 1983…one inch to hen egg size hail was reported in Broomfield with golf ball size hail at Northglenn.

In 1990…dime size hail and thunderstorm wind gusts to 50 mph were reported by storm spotters just east of Aurora near the intersection of Mississippi Avenue and Gun Club Road. The hail and strong winds damaged a number of windows in the area.

In 1991…very heavy rain from slow moving thunderstorms dumped up to 3 inches of rain in 20 minutes in the vicinity of Idaho Springs and central city. Flooding in Idaho Springs forced the closure of the Virginia Gulch Road…which runs from Idaho Springs to Central City. Dirt roads above Central City were damaged or destroyed with the mud being swept onto streets in town. High water in Clear Creek…up to 3 feet above flood stage…washed out a bridge in Idaho Springs. Rock and mud slides forced the closure of I-70 about 1 mile east of Idaho Springs.

In 1997…dry microbursts produced two peak wind gusts to an estimated 60 mph east of Buckley Field.

In 2000…hail as large as 3/4 inch in diameter was measured 5 miles west of Sedalia.

In 2003…a severe thunderstorm produced hail as large as 2.75 inches in diameter at Highlands Ranch. Hail to 3/4 inch was reported in Aurora near Cherry Creek and in Arapahoe County 9 miles southeast of Aurora.

In 2004…heavy thunderstorm rainfall caused flash flooding across central and southern metro Denver. A rain gage at City Park recorded 4.37 inches of rainfall from the deluge. Several roads in and around the city had to be closed due to floodwaters…stranding many vehicles. The Denver fire department conducted at least 15 water rescues. One driver nearly drowned when he made a wrong turn into a retaining pond. Four men who witnessed the accident were able to save the man before his car was completely submerged. Widespread street flooding was reported in the Denver Stapleton area where rainfall totaled 3.81 inches. Standing water over 6 inches deep was reported near I-70 and Quebec…I-225 south of I-70…and I-25 near 6th Avenue. Flood waters reached 8 feet deep in some low lying areas as sewers became clogged and the storm runoff pipes were unable to handle the heavy flow of water. Heavy rainfall caused additional flash flooding south of Denver. Several street intersections in centennial and southern Aurora became impassable due to high water. Two feet of water covered portions of the roadway near Park Meadows Mall. One person had to be rescued near the intersection of Arapahoe Road and Liverpool. Floodwaters forced the closure of Stonegate Parkway near Jordan Road and Lincoln Avenue. Flooding was also reported on Meridian Blvd. near I-25. Rainfall was 1.62 inches at Denver International Airport.

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In 1875…nearly 0.75 inch of rainfall in the city overnight… Possibly assisted by heavier rainfall upstream…produced a decided and rapid rise in Cherry Creek…which washed out some bridges. Other small creeks and streams were filled to overflowing.