Thornton, Colorado, USA
UpdatedSat, 21-Sep-2019 6:30pm MDT 


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Thornton’s Wednesday to offer seasonal temps, slight chance for thunderstorms

Wednesday, August 14th, 2019 5:24am MDT

A pretty good looking summer day ahead for us and for the kiddos heading back to school today. Highs will be right near average for the date and chances for thunderstorms are a bit lower than in recent days.

Sunny to mostly sunny skies will be above this morning. We’ll see a bit of an increase in cloud cover in the afternoon but the sun will still be making appearances.

Some isolated thunderstorms may be seen this afternoon and evening but the best chances for activity will be to our east.

Highs today will top out right close to the average for the date of 88 degrees.

Tonight, some thunderstorms may roll after dark but will end by midnight. Skies will then clear and overnight lows will dip to around 60 degrees.

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August 11 to August 17: This Week in Denver Weather History

Wednesday, August 14th, 2019 3:55am MDT
This week in Denver weather history

August 11 to August 17: This Week in Denver Weather History

Colorado’s unofficial severe weather season may be over but August holds a wide variety of related weather hazards that can be damaging and deadly. Looking back at this week in Denver weather history, flooding, large hail and even tornadoes have made appearances in our past.

From the National Weather Service:


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


In 1872…fog was very dense until about 8:00 am. There was water dripping from the roofs of houses as if it had rained. The rain gage showed 0.01 inch of moisture…even though there had been no rainfall.

In 1927…an apparent dry microburst produced only a trace of rain and brief northwest winds sustained to 34 mph with gusts to 44 mph.

In 1980…hail up to golf ball size caused some roof and car damage in the southern part of Aurora.

In 1990…lightning ignited a storage tank filled with 10 thousand gallons of crude oil in a farmer’s field near Dacono…25 miles north of Denver. Flames shot to 40 feet high for nearly 2 hours before being extinguished. A lightning bolt also struck 21 miles north of Denver at an Erie fire station…causing extensive damage to the gas meter and electrical system. The sudden power surge blew out the station’s television set…a refrigerator…and a pop machine. Small fires spread throughout the structure… Totally destroying the building’s electrical wiring. The fires were quickly extinguished by the in-resident fire fighters. Golf ball size hail was reported in Denver near the intersection of Santa Fe Drive and I-25.

In 2012…a severe thunderstorm produced a wind gust to 60 mph at rocky mountain metropolitan airport.

In 1992…dime size hail fell in Westminster.

In 1994…strong thunderstorms produced large hail across northwest and north metro Denver. One inch diameter hail fell in Brighton with 3/4 inch hail reported in Westminster and at Indian Hills in the foothills west of Denver. Lightning struck a house in Arvada. The resulting fire destroyed one-third of the house. Funnel clouds were sighted over Westminster.

In 1997…large hail…strong winds…and torrential rains hammered portions of Lakewood and south Denver. Nearly 1 inch of rain fell in the span of 10 minutes in south Denver with a storm total of 1.81 inches. Street flooding was extensive as gutters and other drainage systems in the area were clogged by hail…piled several inches deep…and other debris. Strong thunderstorm winds to 50 mph and large hail accompanied by heavy rain caused extensive damage to cars…homes…and businesses. Several trees were downed by the strong winds…and trees were stripped of their leaves by hail. A water lily exhibition on display at the Denver botanic gardens was heavily damaged. Final estimates of the damage included 60 million dollars to automobiles and an additional 68 million dollars to homes and businesses. Hail to 1 1/2 inches in diameter fell in south Denver with 3/4 to 1 inch hail in Lakewood. A man received minor injuries in Aurora when he was struck by lightning while talking on the telephone.

In 2003…hail to 3/4 inch in diameter was measured in Aurora near Cherry Creek.


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.


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 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.

» Click here to read the rest of August 11 to August 17: This Week in Denver Weather History

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Tuesday in Thornton to bring temps a bit warmer than normal, chance for evening storms

Tuesday, August 13th, 2019 4:52am MDT

Today’s weather will look much like yesterday but we throw in the possibility of a thunderstorm in the evening.

Sunny skies start us off and will be with us this morning. A few clouds arrive in the afternoon and will build a bit into the evening. Highs will top out around 90 degrees, a bit above normal for the date.

From about 6:00pm to midnight we may see some gusty thunderstorms, most likely seeing them around sunset.

Skies will gradually clear overnight with lows near 60 degrees.

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Temps a bit above normal, calm, dry conditions for Thornton’s Monday

Monday, August 12th, 2019 4:54am MDT

We start off the workweek with a good looking day of weather. Temperatures will be near normal and we will have lots of sun and no storms.

Sunny skies will be with us throughout the daytime hours. Winds will be calm this morning then become a bit breezy out of the east in the afternoon. Highs today will top out around the 90 degree mark, a couple degrees above normal for the date.

Tonight, mostly clear skies will be above with lows dipping to about 60 degrees. Enjoy!

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Thornton’s weekend to feature seasonal temperatures, chances for storms each day

Friday, August 9th, 2019 5:34am MDT

Pretty typical weather for us over the three day period. Temperatures will be at or close to normal and PM thunderstorms will be seen.

For today, mostly sunny skies will be above this morning then an increase in clouds in the afternoon. Some scattered thunderstorm activity will be seen with gusty winds, some brief rain being possible. Highs today will be in the low 90s. Tonight, storms will end not long after sunset and we will have mostly cloudy skies with lows in the mid-60s.

Saturday will see partly cloudy skies above throughout the day. Highs will be in the upper 80s. Thunderstorms are possible from about noon until sunset or so. Saturday night into Sunday morning, lows will be in the low 60s.

Sunday offers more of the same. Partly cloudy skies will be above and highs will again top out in the upper 80s. We will have our best chance of storms for the weekend that afternoon.

Have a great weekend

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Thornton’s Thursday to offer cooler temperatures, better chance for storms

Thursday, August 8th, 2019 5:37am MDT

A bit of a break from the hot, dry pattern of recent days. Moisture is increasing and will be coupled with cooler air leading to lower temps and better chances for storms.

The day starts with partly clear skies and we will see much of the same for most of the day. High temperatures today should top out in the very comfortable low 80s range.

Thunderstorms will begin to develop around noon, if not a bit before, with our best chances for activity coming after 4:00pm until 8:00pm. Some of the storms will have the potential to deliver a heavy dose of rain and will bear close watch.

Tonight, any storms should end after midnight. Lows tonight will be near the 60 degree mark.

Keep an eye out for the storms here.

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Above normal temps, another chance for a thunderstorm Wednesday

Wednesday, August 7th, 2019 5:36am MDT

More of the same would be a good way to sum up today’s weather. Unseasonably warm mercury readings will continue and we may see a PM storm.

The day starts out with mostly sunny skies and those will be with us into the afternoon. After that, as is normal, clouds will increase.

After about 3:00pm we will see some scattered thunderstorm development that may last into the evening.

Highs today will be in the mid-90s, about five degrees above normal for the date.

Tonight, any lingering storms will wind down leaving partly cloudy skies. Overnight lows will be in the low to mid-60s.

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Tuesday’s temperatures climb, only a slight chance for thunderstorms

Tuesday, August 6th, 2019 5:08am MDT

Things dry out a bit today in the atmosphere and that is going to give us a lesser chance for storms. We will also see more sun helping to drive temperatures higher.

Mostly sunny skies start us off and will be with us until this afternoon. The later hours will see an increase in cloud cover. We see just a slight chance for thunderstorms after about 2:00pm and into the evening.

Highs today will be in the mid-90s.

Tonight, any storm activity should end by about 11:00pm and we will then have partly clear skies. Overnight lows will dip to the low 60s.

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August 4 to August 10: This Week in Denver Weather History

Monday, August 5th, 2019 5:31am MDT
This week in Denver weather history

August 4 to August 10: This Week in Denver Weather History

The beginning of August typically continues our monsoon season. This leads to increased chances for thunderstorms with heavy rain and the associated hazards that come with it. Our look back at this week in Denver weather history highlights the dangers of flooding, hail and lightning and even includes reference to grasshopper swarms being blown into the city.

From the National Weather Service:


In 1988…two inches of rain fell in 3 hours at both Morrison and Wheat Ridge. Thunderstorm rainfall totaled 0.80 inch overnight at Stapleton International Airport.


In 1889…southwest winds were sustained to 42 mph with an extreme velocity to 52 mph.

In 1924…0.01 inch of rain fell over downtown Denver. This along with the 0.01 inch of rainfall on the 10th was the only rainfall of the month…the driest August on record.

In 1963…heavy rains in the foothills above Idaho Springs caused mud and rock slides which closed U.S. Highways 6 and 40 for a time.

In 1976…hail to 1 inch diameter was reported 12 miles southwest of Denver. Hail to 3/4 inch in diameter was reported in Lakewood. Small hail…1/4 to 1/2 inch in diameter…fell at Stapleton International Airport.

In 1982…heavy rain poured through the roof of a clothing store in Aurora…causing widespread water damage. The roof was being repaired when the storm hit.

In 1983…hail up to one inch in diameter fell in Aurora where heavy rain produced street flooding.

In 1984…a Colorado state trooper was struck and injured by lightning in Northglenn.

In 1989…a microburst wind gust to 52 mph was recorded at Stapleton International Airport.

In 1997…lightning sparked a small fire in a home in Arvada… Causing minor damage. Several intersections in both Arvada and Westminster were flooded by thunderstorms producing heavy rain. Several cars were damaged by the high waters… And a number of businesses were flooded.

In 1999…flooding and flash flooding problems developed over metro Denver as slow moving thunderstorms dumped from 2 to 3.5 inches of rainfall in about 3 hours. Near the junction of I-25 and U.S. Highway 36…up to 4 feet of water flooded an auto dealership. About 45 cars were ruined. Damage estimates to the dealership alone totaled nearly a half million dollars. Sections of I-25 and U.S. 36 near the interchange were closed due to floodwaters. Floodwaters… Up to 5 feet deep…forced the evacuation of two mobile home parks in federal heights. Railroad tracks were washed out near Federal Blvd. and 64th avenue. Numerous power outages caused widespread blackouts in Thornton and Littleton. Along Massey Draw near Carr St. and Chatfield Reservoir…4 homes were flood damaged and portions of their backyards washed out. Widespread street flooding was also reported in Boulder where several buildings were flood damaged…including the University of Colorado Memorial Center.

In 2004…two golfers were shocked when lightning struck the eighth green of the golf course at Castle Pines north of Castle Rock. The two men suffered only minor injuries. Heavy thunderstorm rain from the same storm caused flash flooding. Floodwaters rushed across parts of U.S. Highway 85 near the entrance to the Castle Pines Golf Club. The traffic lanes were covered with up to 6 inches of running water.

In 2008…lightning sparked a grassfire that consumed 300 acres on the northern edge of Green Mountain…in Jefferson County. Gusty winds and very dry conditions allowed the wildfire to quickly spread and threaten several houses. Fortunately…only minor damage was reported to homes due to smoke and melted siding.


In 1881…the low temperature cooled to only 76 degrees…the record high minimum temperature for the month.

In 1889…southwest winds were sustained to 42 mph.

In 1918…hail pelted the city…but was light and caused no damage. Precipitation totaled 0.25 inch. Northwest winds were sustained to 31 mph.

In 1964…lightning struck two boys in Denver while playing ball. One was treated and released from the hospital…but the other boy suffered second degree electrical shock and cardiac arrest and was hospitalized in critical condition for several days.

In 1969…two tornadoes touched down briefly in an open field southeast of Buckley Field in Aurora. No damage was reported.

In 1970…heavy rain in the Indian Hills area in the foothills west of Denver caused flash flooding…which washed out roads and damaged other property. Hail accumulated to a 3 inch depth with stones up to golf ball size; however…most of the damage was from flooding.

In 1982…2.38 inches of rain fell in an hour in Arvada… Causing minor flooding on Ralston Creek. In Westminster… 1 1/2 inches of rain fell…causing damage to streets and culverts. In addition…lightning caused some minor power outages across metro Denver.

In 1983…very heavy thunderstorms hit the southern portion of metro Denver. Heavy rainfall…as much as 2.89 inches in 38 minutes…caused widespread street flooding in southeast Denver. Two feet of water covered a section of I-25. Hail up to golf ball size accompanied the storm in Littleton and Englewood…along with 60 mph winds.

In 1984…a heavy thunderstorm drenched Littleton with up to 2.35 inches of rain in an hour…along with small hail that piled up to 2 inches deep. Flood waters were up to 4 feet deep in parts of town with many basements flooded. There were some power outages caused by lightning.

In 1990…a thunderstorm dumped 1.25 inches of rain in 12 minutes near tower and smoky hill roads in southeast Aurora. Minor street flooding was reported in the area.

In 1992…a pilot reported two funnel clouds near Cheery Creek Reservoir. Both dissipated quickly. Dime size hail fell near Franktown.

In 1994…one inch diameter hail fell near Strasburg. No damage was reported.

In 1999…a dog kennel east of Denver International Airport… Was flooded when a small dam…upstream in Elbert County… Was breached. The floodwaters…up to 4 feet deep…washed away some 6-foot fences and other small buildings. Ten of the 70 dogs boarded at the kennel drowned.

In 2002…a mail carrier was struck by lightning as he inserted a key into a multi-unit mailbox in Bailey. The shock knocked the man back against the mail truck. He suffered minor injuries. Lightning struck a residence in Commerce City. The resulting fire destroyed the roof of a detached garage and damaged much of its contents. Hail as large as 1 3/4 inches in diameter pelted Pine. One inch diameter hail fell in Arvada and southwest Denver. Heavy rain triggered a mudslide along U.S. Highway 285 near Bailey. Both lanes of traffic had to be closed until debris could be removed from the highway. Several residences in the Bailey and Glenisle areas were also flooded.

In 2004…heavy thunderstorm rainfall caused localized flash flooding in Virginia Canyon near Idaho Springs. Sections of the Virginia Canyon Road had to be closed due to the floodwaters.

In 2008…a severe thunderstorm produced large hail…up to 1 1/4 inches in diameter…northeast of Parker. Several automobiles were damaged.

6 » Click here to read the rest of August 4 to August 10: This Week in Denver Weather History

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Thornton’s workweek starts with seasonal temps, chance for thunderstorms

Monday, August 5th, 2019 5:30am MDT

A largely typical early August day ahead for us. Temperatures will be near normal and we expect the usual chance for PM storms.

Partly to mostly cloudy skies start us of, perhaps with a few sprinkles of rain but nothing that will amount to anything. The rest of the day should see a bit of sun with partly sunny skies.

The afternoon will see some scattered thunderstorm activity with the best opportunity coming from 2:00pm into the evening. Highs today will be right near the 90 degree mark.

Tonight, any lingering storms will end by midnight leaving partly clear skies. Overnight lows will be in the low 60s.

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