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

Sunday, August 20th, 2023 4:54am MDT

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.

20

In 1980…winds to 55 to 60 mph were recorded in south Boulder.

In 1982…strong thunderstorm winds blasted the Jefferson County Airport near Broomfield…causing an estimated 3 million dollars in damage. At least 5 hangars and 15 airplanes were damaged…many seriously; one hangar was completely destroyed. Torrential rains accompanied the winds. Heavy rains also dumped on Boulder where 1.65 inches fell in just 15 minutes…causing street flooding. Wind gusts to 72 mph were recorded in Boulder. Over half an inch of rain fell in just 5 minutes in Littleton where two homes were struck by lightning. Lightning also struck a house in Arvada where over an inch of rain sent Ralston Creek over its banks. Strong winds accompanied the storms.

In 1984…slow moving thunderstorms dumped 1.25 inches of rain in Evergreen…causing street flooding. A half inch of rain fell in just 18 minutes in southeast Denver. Littleton and Boulder were also drenched with about an inch of rain. Rainfall totaled 0.92 inch at Stapleton International Airport.

In 2001…severe thunderstorms produced damaging winds and large hail across metro Denver. Hail as large 1 inch in diameter fell in Aurora near Cherry Creek. Strong thunderstorm winds gusting as high as 58 mph blew the roof from a building between Thornton and Denver and toppled several trees in Denver. One tree landed on a mail truck. Other thunderstorm winds were clocked to 60 mph near Parker… 62 mph in Broomfield…and 61 mph at Denver International Airport.

In 2006…a tornado (f0) touched down near Bennett…but caused no reported damage.

In 2013…severe thunderstorms pounded the southern Denver suburbs and other parts of the Front Range. In Jefferson County…water rescues were reported for some people in stranded cars. In the Ken Caryl area…large hail from one inch to 1 3/4 inches in diameter was reported. On West Chatfield Avenue in Jefferson County…hail runoff gathered six inches deep in spots and “hail plows” were sent out to clear some streets. Hail up to one inch in diameter was also reported near Castle Rock.

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.

22

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.

22-24

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.

23

In 1900…northwest winds were sustained to 42 mph with gusts to 49 mph.

In 1921…a thunderstorm cloudburst produced 2.20 inches of rainfall in an hour over downtown Denver. This is the greatest 1 hour rainfall on record at the official observing site in the city. Precipitation totaled 2.93 inches…which is the greatest calendar day precipitation ever recorded in August.

In 1941…one man was killed by lightning about 2 miles from the official weather station in downtown Denver.

In 1962…a home near Boulder was destroyed by a lightning- caused fire.

In 1968…strong winds buffeted Boulder briefly during the early morning hours. At the National Center for Atmospheric Research…winds averaged 55 mph with gusts to 85 mph. Damage was minor. Northwest winds gusted to 31 mph at Stapleton International Airport.

In 1977…lightning damaged at least 6 homes in Aurora.

In 2008…a landspout touched down near Westcreek in Douglas County. One man was seriously injured when he tried to escaped several falling trees in his ATV. One of the trees struck his back and broke two vertebra. Another camper narrowly escaped injury. Seconds after he back up his truck…a tree came down where it had been parked.

In 2019…a severe thunderstorm produced large hail…up to 2 1/2 inches in diameter 5 miles west of Byers. Hail up to 1 3/4 inches in diameter was reported near Bennett.

24

In 1880…a thunderstorm produced vivid lightning and heavy rainfall…which caused flooding over the eastern part of the city including the brick yards. There was no rainfall recorded in downtown Denver.

In 1910…an apparent dry cold front caused a remarkable drop in temperature. From 3:00 pm until midnight the temperature fell from a high of 93 degrees to a low of 40 degrees. Northeast winds were sustained to 44 mph during the late afternoon.

In 1946…heavy rain near Idledale caused flooding on bear creek at Morrison…which resulted in one death when a woman was swept from her stranded car and drowned.

In 1973…strong winds blew down a few power lines and hail up to 3/4 inch diameter fell in southeast Aurora.

In 1984…heavy rain hit the south Denver area. Over an inch fell in less than an hour at both Castle Rock and Sedalia.

In 1992…heavy rains caused flash flooding across parts of metro Denver. Rainfall amounts of 1 to 3 inches fell with the hardest hit areas being the southwest and central parts of metro Denver. Bear Creek rose above bankfull near Idledale with flood waters moving into southwest metro Denver. Mud and rock slides along Colorado highway 74 west of Morrison were reported. The confluence of Cherry Creek and the South Platte River in downtown Denver also went out of its banks…flooding bike paths. Rainfall totaled 1.98 inches at Stapleton International Airport where light to moderate rain fell most of the day. Heavy rain and fog briefly reduced the surface visibility to 1 1/2 miles. The temperature climbed to a high of only 58 degrees…which was a record low maximum for the date.

In 2002…hail to 7/8 inch in diameter was measured in southwest Denver.

In 2008…several landspout tornadoes developed along a boundary to the southeast of the Denver metropolitan area during the Democratic National Convention. In northwest Elbert County… Minor damage was reported. The damage consisted of downed power lines…broken windows and an out building. Severe thunderstorms also produced very heavy rain and large hail… Up to one inch in diameter. In southwest Douglas County… Heavy rain caused flash flooding near the town of Westcreek. A mudslide closed State Highway 67. The road in the YMCA camp shady brook was also washed out and some bridges were damaged.

24-26

In 1910…the lowest temperature ever recorded in August…40 degrees…occurred on each of these days and on August 22… 1904. The unusually cold weather for so early in the season brought sub-freezing minimum temperatures to much of the Colorado northeastern plains.

25

In 1951…a microburst produced a southwest wind gust to 50 mph at Stapleton Airport. Only a trace of rain was observed.

In 1964…thunderstorm winds gusted to 59 mph and caused some blowing dust at Stapleton International Airport.

In 1994…lightning struck a power pole in Louisville and caused a two-hour power outage.

In 2008…an unoccupied home was struck by lightning in Aurora… Causing 75 thousand dollars in damage to the roof.

26

In 1944…one of the most destructive hailstorms in the city in a decade caused damage estimated at nearly one million dollars. The storm occurred within a period of 10 to 30 minutes…between 2:00 pm and 3:00 pm. The hail varied in size from very small to as large as 1 1/2 inches in diameter. Hail covered the ground to a depth of 5 to 6 inches in some sections of the city. Several people were cut by broken glass. The hail and heavy rain flooded underpasses to a depth of 6 feet…and the occupants of stalled autos had to be rescued. Sewers were unable to handle the sudden amount of water and water backed up and flooded a number of basements. A few first floors of buildings were flooded. The water department had a busy time replacing manhole covers that had been displaced by the water pressure. Trees were stripped…one was severely broken…and telephone lines were downed. Roofs…windows… Automobiles…awnings…and gardens were severely damaged. Flowers and gardens in some sections of the city were a total loss. Greenhouses were extensively broken with an estimated 20 carloads of glass shattered. Vegetable and truck crops in and around the city were severely shredded. The next day the American Red Cross was designated by the War Agency to grant any and all priorities needed to obtain materials and supplies to replace and repair the damage. In downtown Denver…the thunderstorm produced 0.95 inch of rain and heavy hail along with sustained northwest winds to 25 mph.

In 1961…strong winds blew in the walls of a warehouse under construction in Denver. Two workmen suffered a fractured foot and body bruises.

In 2014…two men in central Denver were struck by lightning as they sat under a tree to avoid a heavy downpour. One of the men was unconscious and had no pulse when emergency responders arrived. He was immediately taken to Denver Health was listed in critical condition. The other victim suffered less severe injuries. He was treated at the scene and hospitalized…then released a few hours later.

26-27

In 1980…two heavy thunderstorms hit Arvada and Westminster… Dumping up to 1.50 inches of rain in less than an hour. At least two streets were washed out and a number of homes and cars were damaged when a creek flooded. Three homes in Arvada sustained minor lightning damage.

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Denver sets record high minimum for August 18

Friday, August 18th, 2023 11:59pm MDT

Record High Temperature

Mother Nature isn’t giving a lot of relief at night from the daytime heat and as a result Denver set a record.

As measured at Denver International Airport, the Mile High City’s low temperature for today was only 69 degrees. This is a good bit warmer than the previous record high minimum of 67 degrees set in 2020.

Thornton virtually matched that reading with a low of 66.5 degrees.

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“Hot” will be the operative word for Thornton’s weekend weather

Friday, August 18th, 2023 5:02am MDT

The heat of summer is far from over as Mother Nature will continue to keep it toasty. The weekend (and the first part of next week) will feature mercury readings well above normal with only small chances for storms.

For today, mostly sunny skies will be above as we head for a high of around 95 degrees. Winds will be breezy this afternoon and evening. Some scattered thunderstorms will be seen, mainly in the late afternoon and evening. Tonight, skies will be partly cloudy with lows in the mid-60s.

Saturday continues with the heat and highs in the mid-90s. It will be sunny in the morning then the afternoon will bring a few clouds and breezy winds. Only isolated thunderstorm activity is expected. Saturday night, clouds will linger and lows will be in the mid-60s.

Sunday looks to be the hottest day of the three-day period. There will be some clouds early but then mostly sunny skies will take over. Highs will reach the upper 90s.

Have a great weekend and stay cool!

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Thornton cools slightly Thursday, breezy winds thrown in the mix

Thursday, August 17th, 2023 4:47am MDT

It won’t be much, but we will cool down a few degrees today. Conditions will remain dry and we will have some breezy winds later today and overnight.

Sunny skies will be with us this morning then a few clouds will move in this afternoon. Mid-afternoon will see the winds become breezy. High temperatures will top out in the mid-90s.

Tonight, winds will pick up speed and become a bit blustery. Skies will be mostly clear with lows in the mid-60s.

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The heat is on for Thornton’s Wednesday

Wednesday, August 16th, 2023 4:53am MDT

The mercury is going to climb today and we will be seeing readings 10 degrees or so above normal.

Sunny skies start us off and will be with us for most of the morning. Late morning and the afternoon will see some clouds but nothing overly intrusive. Some northerly, breezy winds will be seen this afternoon. As for temperatures, look for highs in the upper 90s, well above the average high for the date of 86 degrees.

Tonight, skies will be partly clear and we will cool down nicely. Look for lows in the low 60s.

Keep an eye on those hot temps here.

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Very warm temperatures, calm conditions for Tuesday

Tuesday, August 15th, 2023 4:46am MDT

After a couple of cooler days, the heat returns today. We will see temps a good bit above normal with lots of sun above.

Sunny skies will be the rule throughout the day. Conditions will be calm and dry. Look for highs to reach the low to mid-90s.

Tonight, lows will dip to the low 60s under mostly clear skies.

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Denver sets record low temperature for August 14

Monday, August 14th, 2023 11:59pm MDT

Record Cold Temperatures

Is that a chill in the air? No, not really, but it was cool enough to tie a record.

As measured at Denver International Airport, the Mile High City’s official low temperature for the date was 49 degrees. This ties the previous record low for the date set in 1976.

Here in Thornton, we stayed warmer with a low of 54.6 degrees.

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Thornton’s workweek starts out with pleasant temps, calm conditions

Monday, August 14th, 2023 4:50am MDT

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Following yesterday’s cold front, we will enjoy a day with some very nice mercury readings. Enjoy it while you can as the heat will be back on for the rest of the week.

For today, a few clouds will start us off but they won’t last long and sunny skies will be the general rule for most of the day. Conditions will be calm and dry as we head for a high close to 80 degrees.

Tonight, skies remain mostly clear with overnight lows in the low 50s.

Looking ahead, we may see some of our warmest temperatures of the summer this week. High pressure will be building and the mercury will be climbing. Look for highs in the 90s through the workweek and coming weekend. More details in the extended weather forecast here.

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

Sunday, August 13th, 2023 5:36am MDT

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:

8-13

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

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.

13

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..

In 2019…Hail up to 1 3/4 inches in diameter was observed 4 miles west of Frederick…with hail up to one inch in diameter near Dacono.

14

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. » Click here to read the rest of August 13 to August 19: This week in Denver weather history

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Thornton’s weekend weather to feature temps near normal, some slight chances for storms

Friday, August 11th, 2023 5:02am MDT

A pretty nice looking weekend ahead for us. Temps start out a bit above normal then cool slightly and we only have slight chances for storms.

Friday will be the warmest day of the three day period with highs in the low 90s. Mostly sunny skies will be above. The afternoon and early evening bring a slight chance for a thunderstorms. Saturday night, it will be partly clear with lows around 60 degrees.

Saturday looks much like today, perhaps a couple of degrees cooler. Mostly sunny skies will be overhead with another slight chance for a PM storm. Saturday night, winds will be breezy with lows around 60 degrees under partly clear skies.

Sunday offers up a good dose of sun with highs in the mid-80s. A cold front will move through and that will give a bit better chance for some thunderstorm activity.

Have a great weekend!

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