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June 28 to July 4: This week in Denver weather history

Thursday, July 2nd, 2020 4:13am MDT

This Week in Denver Weather History

As always, an interesting week in Denver and Thornton weather history.  Various severe weather items are noteworthy, none more so than on July 2, 2006 when a teenager wearing an iPod was struck with lightning.  The music player actually contributed to the teen’s injuries by providing a direct route for the electricity into the victim’s head via the headphones.

From the National Weather Service:


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


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

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

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

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

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

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

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

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

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

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

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


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

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

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

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

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

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

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

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


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


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


In 1879…dense smoke from mountain forest fires covered the city and obscured the sun as it set behind the mountains.

In 1900…a thunderstorm produced northwest winds to 44 mph with gusts to 58 mph…but only a trace of rain.

In 1917…north winds were sustained to 47 mph with gusts to 52 mph.

In 1942…a strong thunderstorm produced hail and heavy rainfall in south Denver.  Leaves were stripped from trees and heavy rain caused street flooding which halted traffic.  Hail of unknown size reached a depth of 9 inches on the ground.

In 1965…funnel clouds were observed to the south of Stapleton International Airport and in Jefferson County…15 miles southwest of the airport.  Later…a tornado touched down briefly 1 mile east of Littleton…causing only minor damage. Another tornado was observed 12 miles southwest of Stapleton International Airport in Jefferson County.  Hail to 3/4 inch in diameter fell in the bear valley area…12 miles south- southwest of Stapleton International Airport.  Yet another tornado was sighted 10 miles northwest of the airport. Cloudbursts accompanied by hail battered areas of Arapahoe and Adams counties east of Denver…damaging ripening grain fields.  At Lafayette…3.50 inches of rain fell in 30 minutes…causing some flooding.

In 1982…numerous funnel clouds were observed over southwest metro Denver.  Only one funnel touched down near the intersection of Jewell and Kipling.  The tornado was on the ground for about 5 minutes and caused no damage except for uprooting some trees.  In addition…thunderstorms produced heavy rain and hail in the foothills west of Denver.  Over an inch of rain fell in a short time near Idaho Springs… Causing clear creek to overflow its banks and flood a few low lying areas of the town.  A few people were evacuated… And water and mud entered several stores.  The heavy rain also washed out several roads.  Hail piled up to a depth of 3 to 4 inches near Idaho Springs.   Hail to 3/4 inch was reported at many places across metro Denver including Stapleton International Airport.  Lightning struck a chemistry building on the university of Colorado campus in Boulder and started a small fire.  Thunderstorm wind gusts to 60 mph were reported near Brighton.

In 1984…heavy rain caused some street and basement flooding in Littleton.  One location received 1.56 inches of rain in 75 minutes.

In 1987…a weak tornado near Watkins stayed on the ground for 5 minutes.

In 1990…a small twister touched down in an open field just north of the rocky mountain arsenal.  No damage was reported.

In 1998…hail as large as 1 inch in diameter fell near Evergreen.

In 2005…a severe thunderstorm produced hail as large as 3/4 inch near Roggen.  The hail destroyed a wheat field.

In 2006…the temperature reached a high of 98 degrees at Denver International Airport.  This marked the 19th day in June with a maximum temperature of 90 degrees or more setting a new all-time record for the month.

In 2011…very strong thunderstorm winds were also observed across portions of the urban corridor. A peak wind gust to 65 mph was recorded…2 miles northeast of boulder with a gust to 63 mph at Front Range Airport at Watkins and 7 miles southeast of Denver International Airport.  The peak wind gust measured at Denver International Airport itself was 45 mph.  A severe thunderstorm also produced one inch in diameter hail 2 miles south-southeast of Parker. In addition…a lightning strike destroyed a home in north Denver.


In 1873…heavy rainfall overnight totaled 1.42 inches. Mountain peaks to the southwest of the city were covered with fresh snow on the morning of the 1st.


In 1915…northeast winds sustained to 41 mph with gusts to 50 mph occurred just before a thundershower in the evening. Rainfall was only 0.07 inch.

In 1941…unusually heavy thunderstorm rains flooded basements and blocked traffic.  Water was curb high on many downtown streets.  The thunderstorm also pelted the city with hail of unknown size.  Rainfall in downtown Denver totaled 0.72 inch…but greater amounts likely occurred in other parts of the city.

In 1960…a severe dust devil moving through an Adams County suburban area blew over a fireworks stand…injuring an 11- year-old boy customer and two women operators of the stand. The boy was found under the demolished stand 100 feet away.

In 1961…hail as large as 1 1/4 inches in diameter was reported over east Denver.

In 1967…golf ball size hail fell over portions of metro Denver.  Hail stones to 2 inches in diameter damaged roofs and broke windows in northeast Boulder.  Marble to golf ball size hail fell at the Boulder Airport.  A funnel cloud was sighted over the foothills near Boulder.  Hail stones of 1 to 2 inches in diameter were measured at Jefferson County airport near Broomfield.  Marble size hail fell in the vicinity of Arvada and Westminster.

In 1982…severe thunderstorms dropped large hail in Denver… Boulder…Commerce City…Lakewood…Wheat Ridge…Golden…and Arvada.  Most locations reported hail size from 3/4 to 1 1/4 inches in diameter.

In 1990…the high temperature reached 102 degrees at Stapleton International Airport.

In 1998…hail to 1 1/2 inches in diameter fell near Bennett.

In 2001…the temperature climbed to a high of 101 degrees at Denver International Airport.

In 2016…a severe thunderstorm produced large hail in Castle Rock…ranging in size from 1 to 2 inches in diameter. The hail pummeled neighborhoods as it smashed cars and shattered windows. The storm caused extensive damage to shutters…roofs…siding and fencing.


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.


In 1879…a severe hail storm produced considerable damage in the vicinity of Arvada.  Some of the stones were unusually large…measuring 6.5 inches in circumference (2 inches in diameter) with an average weight of 1 ounce. The stones were uniformly large with one side concave. The greatest damage was to early wheat…cabbage…and vines. A tree just to the south of the weather station in downtown Denver was struck by lightning.  Residents in the house 15 feet away were affected by the strike.

In 1885…thunderstorm winds were sustained to 50 mph in the city.

In 1892…an apparent cold front produced sustained northeast winds to 40 mph with gusts to 45 mph.

In 1955…a apparent microburst wind gust to 69 mph was recorded at Stapleton Airport where the brief strong wind reduced the visibility to zero in blowing dust.

In 1965…hail…up to 2 inches in diameter…struck southwest Adams and northeast Denver counties…damaging cars…windows… And foliage.  Hail accumulated up to a foot deep.  Wind gusts to 48 mph and hail to 1 inch in diameter fell at Stapleton International Airport where the large hail broke three storm windows and shredded shrubs at the U.S. Weather Bureau upper air building.

In 1968…a pilot reported a tornado 10 miles southeast of Parker.

In 1971…one inch diameter hail stones were reported in Adams County about 30 miles east of Denver.

In 1987…a large tornado touched down 10 miles northeast of Stapleton International Airport.  The tornado was vertical and thick and kicked up a large dust and debris cloud. Later…it developed a sinuous rope-like shape as it slowly dissipated.  The tornado was visible for 15 minutes.  The twister occurred in open country and did only minor damage to a metal shed…porch…and mailbox.  A man was killed by lightning in southwest Aurora.  He was in his backyard and had a shovel in his hand at the time of the strike.  A group of soccer players were hit by lightning on a field in Boulder.  A 10-year-old boy was critically injured and hospitalized; fortunately he recovered.  Six other people were knocked to the ground by the strike.  Two of these were slightly injured.  Golf ball size hail fell just east of Littleton and at Highlands Ranch.  Hail as large as 3/4 inch in diameter was reported in Aurora and Parker and near Hudson and Franktown.

In 1988…a 45-year-old man was injured by lightning at Cheery Creek Reservoir.  Administration of CPR probably saved his life.

In 1990…the temperature reached a high of 100 degrees at Stapleton International Airport.

In 1993…thunderstorm winds blew a roof off a barn near Parker…causing an estimated 15 hundred dollars damage.

In 1994…thunderstorm winds downed power lines in Boulder… Causing power outages.  Winds gusted to 66 mph in Boulder… 64 mph in Arvada…and 60 mph in Golden.

In 1998…a small tornado touched down briefly near Barr Lake… But caused no damage.

In 2002…hail as large as 1 3/4 inches in diameter fell in the city of Denver and in Arapahoe County near Littleton. The low temperature of 69 degrees equaled the record high minimum for the date.

In 2006…lightning struck a teenager in Castle Rock as he was mowing his lawn and listening to an iPod.  The teen suffered burns to his hands and feet…and had blood running from his ears when he was found.  The victim’s eardrums were ruptured…which damaged his hearing. Lightning also struck a house in Castle Rock causing extensive damage to the roof and side of the home. Heavy rains caused flash flooding at Castlewood Canyon State Park near Franktown.  The floodwaters destroyed four footbridges along the high trail.  A culvert and several roads were washed out in the area.  In addition… Two driveways crossing Cherry Creek were washed out near prairie canyon ranch.  Heavy rainfall also caused minor flooding on Murphy and Sand Creeks…just east of Buckley AFB.  Gun club road was closed between alameda and Mississippi avenues…north of the Murphy Creek Golf Course…where 3 feet of standing water reportedly covered the road.  A severe thunderstorm produced large hail to 7/8 inch in diameter in south Aurora near Cherry Creek.

In 2016…a weak landspout touched down briefly in and open field near Bennett.


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 2014…a severe thunderstorm produced large… Up to 1 1/2 inches in diameter…about 14 miles northwest of Golden.


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 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.


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.


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

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