Thornton Weather

Thornton’s June 2024 weather preview: Warmer temperatures, increased severe weather

Thornton's June weather preview.Extreme weather can occur during in month in Colorado we well know.  June however is when traditional spring severe weather arrives in the state oftentimes with hail, damaging wind and tornadoes.

Over 40 percent of the tornadoes that occur in Colorado happen during the month of June.  Far more common are thunderstorms with hail and wind, each responsible for extensive damage each year.

While severe weather is common, so too are brilliantly sunny and mild days as we close out spring and enter summer.  If you are looking for cold, it isn’t likely but it is possible as the Denver area has seen freezing temperatures and yes, even snow, during the month.

Read more about Thornton and Denver’s June weather and a look ahead at this year.

Weather History

June 2 to June 8: This Week in Denver Weather History

Leave a comment

This Week in Denver Weather History

June is when Colorado sees the majority of its severe weather and our look back at this week in Denver weather history highlights this fact. Many occurrences of damaging and deadly lightning, powerful winds, large hail and of course tornadoes are seen.

From the National Weather Service:

1-2

In 2002…unusually very warm weather for so early in June resulted in two temperature records. Maximum temperatures of 96 degrees on the 1st and 93 degrees on the 2nd were record highs for each date…respectively.

1-4

In 1977…unusually warm weather for this early in June resulted in 3 maximum temperature records being equaled at the time: 88 degrees on the 1st…90 degrees on the 2nd… And 93 degrees on the 4th. Maximum of 91 degrees on the 3rd was not a record.

1-30

In 2012…it was the hottest June in Denver since weather records began back in 1872. The average temperature for the month was 75.0 degrees which was 7.6 degrees above normal. There were a total of seventeen 90 degree days in  the month of June. The highlight of record setting month was a stretch of five consecutive 100 degree days from the 22nd to the 26th. This was only the third time in Denver weather history in which this happened. Two of the high temperatures during the stretch peaked at 105 degrees… which set the all time record for the month of June and tied the all-time maximum temperature for Denver.

2

In 1914…flooding occurred on Boulder creek when heavy rains added to heavy snowmelt runoff. Flooding damaged the water supply system from the mountains into Boulder and destroyed roads and bridges in the canyons above Boulder. The flooding in central Boulder was described as the worst since the tragic flood of May 29th through June 3rd in 1894. However…there was no reported loss of life. The flood waters also inundated pasture land to the east of the town.

In 1951…the lowest recorded temperature in June…30 degrees… Occurred. The unusually cold weather was accompanied by 0.3 inch of snowfall. Precipitation…both rain and melted snow…totaled 0.30 inch.

In 1966…microburst winds gusted to 51 mph at Stapleton International Airport.

In 1981…a severe thunderstorm roared through metro Denver… Dumping 2.00 inches of rain in as little as 20 minutes and bombing many areas with hail to 1 3/4 inches in diameter. The heavy rain caused local flooding with up to 3 feet of water in some streets in northwest metro Denver. Part of a street was washed out in Thornton. Lightning strikes started a fire and caused a power outage just north of Denver. Lightning also struck a barn which burned to the ground in Brighton. Numerous cars sustained minor hail damage. A tornado was spotted 4 miles northeast of the rocky mountain arsenal…but caused no damage.

In 1982…severe thunderstorms produced large hail across metro Denver. Hail to 3/4 inch in diameter was reported in Louisville and northeast Denver. Golf ball size hail fell near Strasburg where two tornadoes were also sighted.

In 1983…a tornado touched down 5 miles south of Bennett. It destroyed an outbuilding and did extensive damage to greyhound dog shelters. Golf ball size hail fell near the tornado…destroying some hay.

In 1985…3/4 inch hail fell in southwest metro Denver.

In 1989…large hail fell over eastern and central Denver. A few stones were as large as baseballs…and many ranged from 3/4 inch to golf ball size. The hail piled up 2 to 4 inches deep in some areas. Hail to 3/4 inch fell at Buckley Field in Aurora…and 7/8 inch hail fell just east of Aurora. A home in Louisville was struck by lightning and was 30 percent destroyed by the ensuing fire.

In 1991…strong thunderstorm winds in Arapahoe County…14 miles southeast of Stapleton International Airport…damaged the roof of a home and a radio antenna. A funnel cloud… 4 miles northeast of Stapleton International Airport…was sighted for 11 minutes by national weather service observers.

In 1993…a tornado touched down briefly in south Denver… Destroying the 4-inch thick concrete roof of a building and causing about 20 thousand dollars in damage. The twister also picked up a trash dumpster and dropped it onto a car 30 feet away…causing an estimated 3 thousand dollars in damage. Hail up to an inch in diameter fell in Aurora… Conifer…and Bennett. Two funnel clouds were spotted near Deckers. A funnel cloud was sighted for 19 minutes by National Weather Service observers to the southwest of Stapleton International Airport.

In 1994…lightning struck two homes in Denver…starting fires which caused considerable damage to both. Hail to 3/4 inch in diameter fell in Golden.

In 1995…lightning struck a house in Nederland…causing a fire that was doused by subsequent rainfall. A portion of the roof and wall was damaged. The storm also left most of Nederland without power for two hours. Lightning also struck a high chimney of an elementary school in west Denver. The jolt sprayed bricks around the school yard and parking lot. Twenty students and teachers were in the school building at the time…but all escaped without injury. A funnel cloud was sighted over Fort Lupton…and 3/4 inch hail fell in Lafayette.

In 2003…severe thunderstorms produced strong winds and large hail. Hail as large as 1 1/2 inches in diameter fell near Parker. Estimated wind gusts to 70 mph occurred near Parker and near Denver International Airport where thunderstorm wind gusts to 52 mph were recorded. Wind gusts to 60 mph were estimated near Bennett.

In 2005…a severe thunderstorm produced hail as large as 1 inch in diameter in the city of Denver. A tornado was sighted near Bennett along with 3/4 inch hail.

In 2008…severe thunderstorms produced large hail over western Arapahoe…northern Denver and southern weld counties. Hail…2 inches in diameter…was observed near Brighton; with hail to 1 1/2 inches in diameter…5 miles east of prospect. Hail to one inch in diameter was observed near Buckley Field…Frederick and Denver.

In 2012…severe thunderstorm produced damaging thunderstorm winds.  Peak wind gusts included:  82 mph near Strasburg… 61 mph at Buckley Field…60 mph near Byers and southwest Denver…58 mph near Watkins and 52 mph at Denver International Airport.  The microburst winds caused extensive tree and roof damage.  In addition…hail up to 1 inch in diameter was reported 3 miles east-southeast of Parker.

In 2019…lightning struck a home in Broomield. Minor damage to the roof was observed.

2-4

In 1989…heavy rain drenched metro Denver with the greatest amounts recorded on the 3rd. Total rainfall ranged from 1 1/2 to 3 inches. Roads were washed out in Boulder County… And flooded basements caused water damage to houses in the Gunbarrel section of Boulder. In suburban Denver…heavy rain caused minor flooding along Lena Gulch in Jefferson County where two mobile home parks were evacuated. Rainfall totaled 1.66 inches at Stapleton International Airport.

2-7

In 1921…heavy rainfall for nearly a week…on top of streams already swollen by mountain snowmelt…produced widespread flooding over the South Platte River basin…including the tributaries through the canyons to the west and southwest of Denver. Heavy rainfall over the 6-day period totaled 3.36 inches in Boulder…4.98 inches in Morrison…4.27 inches in Castle Rock…and 2.94 inches in the city of Denver. Rainfall amounts in the foothills were estimated between 3 and 6 inches. The narrow-gage tracks of the Colorado and southern railroad were destroyed in the Platte Canyon. From the mouth of the canyon through the city to near Brighton… The river spread from 1/2 to nearly 1 1/2 miles wide… Flooding farm and pasture land and destroying or damaging many bridges. In the city…many businesses along with as many as 500 homes were inundated…forcing their evacuation. Bridges were swept away. The high waters flooded the rail yards and stock yards in lower downtown…closing three adjacent packing houses. The heavy rains also caused flooding on Boulder creek in Boulder on the 6th.

3

In 1951…a trace of snow fell at Stapleton Airport.

In 1961…torrential rains fell 10 to 30 miles north of Denver…causing flooding in the town of Frederick. The rush of water broke through and over a retaining dike sending a 5-foot wall of water into the town…flooding homes and damaging sewer lines…roads…and streets. Golf ball size hail fell in derby…west Denver…and Lakewood…causing more than one million dollars in damage.

In 1981…severe thunderstorms produced tornadoes over metro Denver. The first tornado touched down at the intersection of Alameda Ave. and Sheridan Blvd. The twister moved north along Sheridan Blvd….damaging businesses…apartment buildings…homes…and vehicles. Over ten homes were unroofed. The roof of one landed in the middle of a neighborhood park. At least 10 mobile homes were wrecked. The tornado curved to the northeast into northwest Denver… Hopping up and down in several places. Very strong winds outside the actual funnel caused 20 to 30 thousand dollars in damage in downtown Denver. The third floor of one old building was demolished. No major injuries were reported from the tornado…although several people were hurt slightly in traffic accidents on Sheridan Blvd. In the confusion caused by the storm. Damage in Lakewood alone was estimated at 200 thousand dollars. At the same time… The worst tornado to ever hit metro Denver struck Thornton. Coming from the same thunderstorm that spawned the Denver twister…the Thornton tornado tore a swath through the heart of the city. 87 homes were destroyed…110 others damaged at least moderately. In all…600 homes in a 100 block area sustained some damage. The twister also hit shopping centers…several restaurants…and other buildings. Seven of the 42 injured were considered serious. The storm was strong enough to snap lamp posts in half and drive a 6- inch slab of wood 2 feet into the ground. Damage was estimated at up to 50 million dollars. The same storm that struck Thornton produced another damaging tornado that touched down in the northwest section of Fort Lupton. This twister damaged 16 homes and numerous cars and campers. Two children were slightly injured when the car they were in was knocked about and its windows shattered by the storm. The twister also damaged two commercial buildings. Damage was very spotty…and observers said the storm hopped up and down at least 3 times. Dollar damage was estimated at 500 thousand dollars. The thunderstorm complex that produced 3 damaging tornadoes also dropped large hail which damaged many cars over northwest Denver. One to 2 inches of rain fell in less than an hour…flooding a mobile home park with 3 to 4 feet of water on the northwest edge of Denver. The high water damaged about half of the 392 homes in the park. Local flooding was also reported in other areas across metro Denver. A tornado was also sighted near Franktown…but caused no damage. A thunderstorm wind gust to 52 mph was recorded at Stapleton International Airport.

In 1982…a cold air funnel cloud touched down briefly in southwest Denver. Two tornadoes were briefly spotted near Watkins. No damage was reported from these storms. A brief funnel cloud was sighted by national weather service observers at Stapleton International Airport where 1/4 inch hail fell.

In 1984…there were several sightings of tornadoes around Parker. No damage was reported.

In 1985…a tornado just southeast of Aurora was spotted by a national weather service employee. No damage was reported. Severe thunderstorms pummeled the metro area with hail. One inch to baseball size hail was reported in south Lakewood…one inch hail in Littleton…3/4 inch to 1 inch hail in Aurora…and golf ball size hail in south Denver.

In 1989…hail up to golf ball size fell over Arvada. A golf course had to be evacuated as the hail accumulated up to 3 inches deep in some places. One inch diameter hail fell in west Denver and Westminster.

In 1993…an early morning thunderstorm produced lightning… Which caused an attic fire at a residence in Niwot northeast of Boulder. Damage was estimated at 40 thousand dollars. No one was injured.

In 1994…hail to 1 1/2 inch diameter fell just northeast of Boulder. One inch diameter hail fell in Golden. Thunderstorm wind gusts to 70 mph were recorded in erie.

In 1995…a tornado was sighted over open country near Strasburg. No damage was reported. A funnel cloud was sighted 11 miles east of Aurora where 3/4 inch hail fell.

In 2001…severe thunderstorms produced large hail over east and southeast metro Denver. Hail as large as 1 3/4 inches in diameter fell at Centennial Airport with 1 1/2 inch hail near Buckley Field…1 1/4 inch hail in Parker…1 inch hail near Elizabeth…7/8 inch hail at Cheery Creek Reservoir…and 3/4 inch hail 20 miles north of Kiowa in Elbert County.

In 2002…severe thunderstorms dumped large hail across metro Denver. Hail to 1 3/4 inches in diameter fell over southeast Denver and 4 miles north of Aurora. Hail to 1 1/4 inches pelted Parker. One inch hail was measured near Ft. Lupton…and 3/4 inch hail fell 9 miles southeast of Buckley Field…near Strasburg…and at the site of the former Stapleton International Airport.

In 2005…thunderstorms producing heavy rain and hail caused flash flooding over parts of southeast metro Denver. People became trapped in their vehicles by the high water… And numerous water rescues were required. The hardest hit areas included the vicinity of I-25 and Alameda Avenue…as well as the intersection of Yale Avenue and Quebec Street. Several basements were flooded along Eastman Place. Severe thunderstorms brought heavy rain and hail to eastern Centennial and southeastern Aurora. Up to 3 feet of standing water was reported on east orchard road where several motorists were stranded in their vehicles and needed to be rescued. Hail to 3/4 inch in diameter fell in the area. Ten vehicles were stranded on Grand Avenue…and most had to be towed once the floodwaters receded. Water was reportedly chest deep at one location on Girard Avenue. Hail as large as 3/4 inch in diameter also was reported in Littleton…near Parker…and near Buckley Air Force Base. Hail to 7/8 inch was measured near Sheridan and Cheery Creek Reservoir.

3-4

In 1904…a thunderstorm during the early morning of the 3rd turned into widespread general rain…which continued into the early afternoon of the 4th. Rainfall totaled 2.04 inches.

4

In 1878…a “waterspout” or cloudburst of rain was sighted up the South Platte canyon at around noon. The resulting high waters on the South Platte River slightly damaged a railroad bridge in the city.

In 1937…a trace of snow fell in downtown Denver where rainfall totaled 0.25 inch. Minimum temperature of 34 degrees was a record low for the date. Northeast winds were sustained to 22 mph.

In 1951…the start of the second shortest snow-free period on record…109 days…occurred with the last snow of the season…a trace…on the 3rd. The first snow of the next season occurred on September 21st when 4.2 inches of snow fell at Stapleton Airport.

In 1954…a microburst produced brief sustained winds of 40 mph with gusts as high as 64 mph at Stapleton Airport.

In 1956…the failure of the Georgetown dam caused downstream flooding on clear creek at Idaho Springs and Golden.

In 1976…funnel clouds were sighted near Brighton…Erie…and Dacono…all north of Denver. A tornado touched down briefly 1 1/2 miles east of Lafayette. Another tornado touched down briefly at Hyland Hills Golf Course in Westminster. No damage was reported.

In 1983…severe thunderstorms during the afternoon produced 3/4 inch hail in south Denver…golf ball size hail 5 miles west of Parker…1 1/4 inch hail in Littleton…1 1/2 inch hail in south Aurora.

In 2001…hail as large as 1 inch in diameter fell 17 miles north of Bennett in Adams County.

In 2005…snow was mixed with rain for nearly an hour at Denver International Airport during mid to late morning. The temperature at the time was 45 degrees. Precipitation totaled 0.36 inch for the day. Northwest winds gusted to 37 mph.

In 2008…a severe thunderstorm produced large hail…up to 1 3/4 inches in diameter in Arvada…a northwest suburb of Denver. Several vehicles were damaged. In addition…a severe thunderstorms produced hail to 1 inch in diameter… 10 miles northeast of manila…east of Denver International Airport.

In 2015…severe thunderstorms broke out across Boulder… Denver…Elbert…Jefferson and southern Larimer Counties. Two large and long lived tornadoes developed near Berthoud and near Simla. The tornado that occurred along the Boulder and Larimer county line.  It first touched about 3 miles south of Berthoud…and then tracked to the west/northwest and lifted about 6 miles southwest of Berthoud. The majority of the damage was EF1…with some areas of EF2… and a few small areas of EF3. At least 25 homes between Longmont and Berthoud were damaged; three of them destroyed. No injuries were reported as the winds tore apart homes and rolled vehicles. The EF3 rating is defined as maximum winds estimated at 135 to 140 mph. The path length was 6 miles long with a width of one quarter mile at times. Large hail from quarter to tennis tennis ball size was observed.  The largest hail occurred in northeast Boulder County. The hail damaged cars and homes; breaking windows and windshields.  In addition… numerous roads were closed along the Larimer and Boulder county line due to flash flooding. Just west of Berthoud… 3.47 inches of rain had fallen.  At Denver International Airport…only 0.01 inches of rainfall was recorded… with a peak wind gust to 35 mph from the northeast.

In 2020…severe thunderstorms produced intense wind gusts across parts of Adams and Denver counties. A peak wind gust of 64 mph was observed near Bennett…with a gust to 58 mph observed at Denver International Airport.

Continue reading June 2 to June 8: This Week in Denver Weather History →

Climatology, Thornton Weather

May 2024 Weather Recap: Mild temps, dry conditions and some severe weather

Thornton, Colorado May 2024 Temperature Summary. (ThorntonWeather.com)
Thornton, Colorado May 2024 Temperature Summary. (ThorntonWeather.com)

Most of the month of May 2024 was notable for its mild temperatures and dry conditions. It went out like a lion, however, with a damaging hailstorm.

The first eleven days of the month saw no precipitation at all in Thornton. A few warmer-than-normal days were seen during that period but temperatures were not particularly warm.

Most notable during the first third of the month was the appearance of the aurora. Thanks to some unusually strong solar activity, the celestial event was visible even in the city for a couple of nights.

We finally received our first precipitation of the month on the 12th with a very good, wet event. The next two weeks saw some lighter showers here and there. Temperatures warmed with numerous days seeing readings well into the 80s.

Mother Nature decided to close out the month in dramatic form. Severe thunderstorms arrived around 9:30pm on the night of the 30th, bringing hail up to 2 inches in diameter to the area. Damage was significant and while the rain that came with it was welcome, most residents would have preferred to have gone without.

Thornton ended the month with an overall average temperature of 59.1 degrees. This was well above the 18 year running average for the month of 56.7 degrees. It was the fifth warmest May during that period.

Temperatures ranged from a high of 87.3 degrees on the 17th down to a low of 36.0 degrees on the 2nd.

Out at DIA where Denver’s official measurements are taken, the Mile High City recorded an average temperature for the month of 56.9 degrees, 0.5 degrees below their long-term average. Their highest temperature for the month was 83 degrees on the 29th and their lowest of 30 degrees occurred on the 2nd.

In terms of precipitation, it was a dry one. Thornton saw 1.39 inches fall into its bucket. The majority of that came along with the hail storm on the 30th. That was well below the 1.74 inches average over the past 18 years and puts May 2024 into the books as our driest May during that period.

Denver fared slightly better with 1.70 inches observed at the airport. This was a good bit below the Mile High City’s May average of 2.16 inches for the month.

No snow was recorded in Thornton or Denver during the month.

Click here to view Thornton’s complete May 2024 climate summary report.

Thornton, Colorado May 2024 Precipitation Summary. (ThorntonWeather.com)
Thornton, Colorado May 2024 Precipitation Summary. (ThorntonWeather.com)
Photography, Thornton Weather

May 2024 top shots: Monthly photo slideshow

The aurora lights up the skies at Jackson Lake State Park. (© Patrick Martin)
The aurora lights up the skies at Jackson Lake State Park. (© Patrick Martin)

Colorado’s famously highly variable weather seems to showcase itself during the month of May when a variety of weather conditions can be seen.  This provides a prime opportunity for photos of everything weather to flora to fauna.

The month of May can bring extremes.  Snow is not entirely uncommon during the month but more common is severe weather, particularly in the latter half of the month.  Thunderstorms become more frequent and their associated hazards – lightning, wind, hail and tornadoes – are usual visitors.  Providing additional subjects for pictures are the emerging spring flowers and our abundant wildlife.

  • Slideshow updated May 31, 2024. To learn more about how to send your photo to us for inclusion in the slideshow, see below the slideshow.

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather-related imagery.

Sunsets, sunrises, wildlife and of course every type of weather condition are vividly depicted in images captured from yours and our cameras.

What is missing in the slideshow above?  Your photo!

Our monthly photo slideshow is going to feature images that we have taken but more importantly images that you have captured.  The photos can be of anything even remotely weather-related.

Landscapes, current conditions, wildlife, pets, kids.  Whimsical, newsy, artsy.  Taken at the zoo, some other area attraction, a local park, a national park or your backyard.  You name it, we want to see and share it!

Images can be taken in Thornton, Denver or anywhere across the extraordinary Centennial State.  We’ll even take some from out of state if we can tie it to Colorado somehow.

We’ll keep the criteria very open to interpretation with just about any image eligible to be shown in our slideshows.

What do you win for having your image in our slideshow?  We are just a ‘mom and pop’ outfit and make no money from our site so we really don’t have the means to provide prizes.  However you will have our undying gratitude and the satisfaction that your images are shared on the most popular website in Thornton.

To share you images with us and get them included in the slideshow just email them to us or share them with ThorntonWeather.com on any of the various social media outlets.  Links are provided below.

So come on, get those camera’s rolling!

Weather History

May 26 to June 1: This Week in Denver Weather History

Leave a comment

This Week in Denver Weather History

Our look back at this week in Denver includes a stunning array of extraordinary weather. Typical springtime severe weather with hail, damaging wind, tornadoes and deadly lightning are very prevalent. Snow has even made an appearance on more than one occasion.

From the National Weather Service:

18-26

In 2023…smoke and haze from massive wildfires in Canada significantly impacted air quality and visibility across Denver and the rest of northeast Colorado.

20-27

In 2002…lightning sparked a wildfire near Deckers. Extremely dry conditions and very strong winds the following day allowed the fire…known as the Schoonover…to consume 3850 acres before it could be contained. Thirteen structures were destroyed…including 4 homes…resulting in 2.2 million dollars in damage.

24-26

In 1996…a late spring snowstorm dumped 4 to 10 inches of snow over the Front Range foothills. Conifer picked up 10 inches of new snow; Aspen Springs…9 inches; and Central City…8 inches. The sticky…heavy snow clung to power lines and pulled tree branches down…causing power outages to about 1200 homes in the Conifer area. It took up to 6 hours to restore power to some residences. Lightning struck a telephone data cabinet in Conifer on the 25th…which knocked out phone service to about 1500 customers. Widespread rain fell across metro Denver… Where rainfall totaled 2.07 inches at the site of the former Stapleton International Airport and 1.66 inches at Denver International Airport where north winds gusted to 24 mph on the 26th.

In 2010…high winds preceding a cold front…swept across the Front Range foothills and urban corridor. In Aurora… The wind damaged the roof of Rangeview High School. In Conifer and Denver…the wind downed trees and power lines and caused several brief outages. The downed power lines also caused several cars to catch fire in the vicinity of 1590 Cook St. in Denver. Peak wind gusts included: 82 mph at Highlands Ranch…67 mph…4 miles east of Franktown and Longmont; 65 mph in Boulder…64 mph in Centennial and Denver International Airport…62 mph near Parker and 60 mph in Arvada.

25-26

In 1950…a major storm dumped 10.0 inches of snowfall downtown and 10.7 inches at Stapleton Airport where northwest winds gusted to 30 mph on the 25th. The storm caused extensive damage to utility wires and trees which were in full leaf. A daily record minimum temperature of 31 degrees occurred on the 25th. This was the coldest temperature on this date in 79 years and for so late in the season.

In 1989…a late season snow storm dropped snow as low as 6 thousand feet along the Front Range. Most places in the foothills had 2 to 5 inches of snow. Overnight rainfall totaled 0.33 inch at Stapleton International Airport where north winds gusted to 37 mph on the 25th.

In 1994…lightning struck a television transmitter on Lookout Mountain near Golden and burned out a switcher…which disrupted cable service for 2 hours.

26

In 1897…apparent post-frontal north winds were sustained to 42 mph with gusts as high as 48 mph.

In 1942…the all-time highest recorded temperature in May…95 degrees…occurred.

In 1978…two children were struck and killed by lightning on a junior high school playground in Parker.

In 1987…1 inch diameter hail fell near Boulder and Bennett. The hail was fairly soft and caused no damage.

In 1993…dry thunderstorms produced wind gusts to 81 mph at Jefferson County Airport near Broomfield. Several trees were blown down by the strong winds. Microburst winds gusted to 51 mph at Stapleton International Airport.

In 1995…a woman was injured in Littleton when the car she had just entered was struck by lightning. All of the windows in the car were blown out by the strike. A funnel cloud was sighted near Littleton.

In 2000…a strong microburst wind gust to 92 mph flipped a small airplane on its back and blew a dc-3 loose from its moorings…which allowed it to roll onto a grassy field at Front Range airport near Watkins.

In 2010…severe thunderstorms pounded parts of the urban corridor with very large hail…heavy rain…damaging winds and a tornado. The hail…ranging in size from 1 inch to 2 3/4 inches in diameter…struck Brighton…Commerce City and northeast Denver the hardest. The storms continued to spread destruction to the north and east…impacting byers…Hudson…Deer Trail and Prospect Valley. The combination of hail and wind stripped the bark and branches from trees. Numerous accidents were reported as the hail accumulated up to a foot deep. Snowplows were called out to clear the roadways. Flash flooding occurred along State Highway 52 between Hudson and Keenesburg…and forcing the closure of the highway. Widespread crop damage was also reported as the area was inundated with up to 18 inches of water. Extensive damage to homes…businesses and automobiles was reported with the damage estimated to be around 70 million dollars. A tornado touched down near Denver International Airport…but did no damage. Lightning struck a child in Commerce City while she was watching television. She suffered minor injuries to her leg. At the Rocky Mountain Arsenal Wildlife Refuge…a lightning strike killed a bison. At Denver International Airport…only 0.01 inch of rainfall was observed…along with a peak wind gust to 48 mph from the southeast.

In 2016…severe thunderstorms produced hail up to one inch in diameter near Castle Rock…The Pinery and Watkins.

In 2019…severe thunderstorms broke out across parts of Adams…Arapahoe…Denver…and southern Weld counties during the late afternoon and early evening. The hail ranged from 1 to 1 1/2 inch in diameter. At Denver International Airport…up to 3 inches of hail accumulated on runway surfaces. Consequently…dozens of flights were either delayed or cancelled so runways could be cleared and aircraft inspected for hail damage. A peak wind gust to 44 mph was observed from the west at Denver International Airport…with 0.65 inch of rainfall.

26-31

In 1995…a cool period with light morning showers and moderate to heavy afternoon showers and thunderstorms pushed rivers already swollen from mountain snow melt over their banks causing minor flooding. Streams and rivers such as the South Platte and Boulder creek flooded meadowlands…bike paths…roads near streams…and other low lying areas. No significant property damage was reported and crop damage was unknown. Rainfall totaled 1.79 inches at the site of the former Stapleton International Airport and only 1.51 inches at Denver International Airport.

27

In 1874…an apparent thunderstorm gust front reached the city at 6:40 pm. Strong southwest winds sustained to 48 mph for a few minutes produced large columns of dust in the city and on the prairie. There was no rain in the city.

In 1942…a duststorm swept into the city…but no damage was reported. West winds were sustained to 23 mph.

In 1953…a heavy hailstorm caused an estimated 100 thousand dollars damage across metro Denver. Larger than golf ball size hail fell in Westminster and north Denver. Only 1/8 inch hail was measured at Stapleton Airport.

In 1955…west-northwest winds at 35 mph with gusts as high as 58 mph briefly reduced the visibility to 1/2 mile in blowing dust at Stapleton Airport.

In 1981…lightning damaged power lines west of Lakewood and blew up a transformer at the Denver Federal Center. Hail 1 to 1 1/2 inches in diameter was reported in Lakewood and on I-25 south of Denver.

In 2001…hail as large as 3/4 inch in diameter was measured near Commerce City.

In 2003…hail to 3/4 inch in diameter fell near central city.

In 2006…unusually warm weather for late May produced two temperature records. The high temperature of 93 degrees was a record maximum for the date. The low temperature of 59 degrees equaled the record high minimum temperature for the date. Both previous records occurred in 1895.

28

In 1884…a thunderstorm apparently produced large hail. The hail stones were noted as unusually large…but the diameter of the stones was not measured. The hail fell for only 5 minutes. Precipitation from the storm was only 0.05 inch.

In 1898…heavy thunderstorm rainfall totaled 1.74 inches in downtown Denver. Hail of unknown size accompanied the storm.

In 1981…a woman in Aurora was struck and killed by lightning. Another bolt injured a boy on a bicycle at about the same time a short distance away. About half an inch of rain in 20 minutes caused street flooding in the area. A tornado touched down for about 2 minutes some 3 miles north of Stapleton International Airport.

In 1982…severe thunderstorms produced golf ball size hail in southeast Denver…Aurora…and Strasburg. The large hailstones undoubtedly damaged some cars in the area. At Stapleton International Airport…only 1/2 inch diameter hail was measured.

In 1991…golf ball size hail fell in Brighton. No damage was reported. Later…hail ranging in size from 3/4 inch to 1 1/2 inches in diameter fell over southwestern sections of metro Denver. In some areas…hail piled up a few inches in depth.

In 1994…thunderstorm wind gusts to 65 mph damaged 16 small airplanes and a hangar at Centennial Airport.

In 2001…severe thunderstorms produced large hail across metro Denver. Hail as large as 1 inch in diameter fell in Lakewood…Wheat Ridge…northwest Denver…near Watkins… Bennett…and Keenesburg. Hail 3/4 inch or larger fell in Brighton. Thunderstorm winds gusted to 58 mph at Denver International Airport. A small tornado (f0) touched down near Bennett…but did no damage.

In 2019…a severe thunderstorm broke out over metro Denver during the overnight hours. Some damage was reported to cars and vegetation. The hail ranged in size 7/8 inch to 1 1/4 inch in diameter. Broadcast media reported damage to 16 different greenhouses around Denver; seven experienced significant damage. In addition…two separate storms passed across Denver International Airport. The hail accumulated on the runways but no damage to aircraft was reported.

29

In 1934…the low temperature dipped to only 66 degrees…the all-time record highest minimum temperature for the month of May.

In 1958…a microburst caused a brief wind gust to 56 mph at Stapleton Airport.

In 1964…heavy rain caused flooding in the Harvey Gulch area of southeast Denver. The high water damaged homes… Businesses…streets…and bridges. At Stapleton International Airport…1.33 inches of rain were measured with 1.76 inches total rainfall on the 29th and 30th. The heavy rain during the last week of the month was the first significant precipitation since April 3rd.

In 1967…3/4 to 1 inch diameter hail stones fell in the city of Denver…but caused no reported damage. Hail as large as 3/4 inch was measured at Stapleton International Airport.

In 1975…the heaviest last snowfall of the season occurred when 5.6 inches of snow were measured at Stapleton International Airport. Rain all day on the 28th changed to snow on the 29th and accumulated to a depth of 4 inches on the ground. Northwest winds gusted to 31 mph. Precipitation (rain and melted snow) on the 28th and 29th totaled 1.48 inches.

In 1982…one man was killed and two others injured by a lightning strike as they stood under a tree in the city of Denver’s washington park.

In 1987…7/8 inch diameter hail fell near Castle Rock.

In 1990…thunderstorms over metro Denver produced several small funnel clouds and two small tornadoes. The first tornado (f0) touched down in northwest Denver and caused roof damage to a house and snapped off the tops of several trees. A second tornado (f1) touched down in Northglenn and moved into Thornton damaging a group of self storage garages…several vehicles…a wooden fence…several trees… And the roof of an auto parts store. No injuries were reported. The storms also caused minor street flooding across northern and western sections of metro Denver. Rainfall totals ranged from 1 to 3 inches. Lightning started a small fire at a home in northwest Denver. The fire was confined to the front rooms and was quickly extinguished. Snow plows were used to clear 2 to 4 inches of pea to marble size hail from a stretch of U.S. Highway 285 in Turkey Creek Canyon. Lightning felled a tree in northeast Denver…while strong winds snapped off several large tree limbs in the same area. Thunderstorm rainfall totaled 0.82 inch at Stapleton International Airport where southwest winds gusted to 30 mph.

In 1991…lightning struck a 13 year old boy in a field in Fort Lupton. The boy was in critical condition in an area hospital for 2 days before recovering.

In 1995…lightning struck a soccer goal post and injured 6 adults viewing a soccer game in Arvada. Although no one received a direct hit from the lightning…all escaped with only minor injuries…except one woman who was hospitalized.

In 1996…large hail…3/4 to 1 1/2 inches in diameter… Struck Lakewood and west Denver. Lightning sparked a small fire when it struck an oil storage tank 5 miles west of Brighton.

In 2001…lightning sparked a fire in an apartment complex in Aurora…forcing the evacuation of 24 units. Most of the fire damage was confined to the attic. Damage was estimated at 100 thousand dollars.

In 2004…a man and his son were struck by lightning while practicing on the driving range at the Meadows Golf Club in southwest metro Denver. The father was killed by the bolt…and his 16 year old son seriously injured. Three other people standing nearby received only minor injuries.

In 2010…hail up to 7/8 inch in diameter was reported in Broomfield.

In 2017…an isolated thunderstorm produced hail up to 7/8 inch in diameter near Centennial.

Continue reading May 26 to June 1: This Week in Denver Weather History →

Weather History

May 19 to May 25: This Week in Denver Weather History

Leave a comment

This Week in Denver Weather History

Severe weather takes to the forefront in our look back at this week in Denver weather history. We see many historical flooding events that were commonplace in the late 19th / early 20th century before controls were put in place. Almost everyone will recall the Windsor tornado, an EF3 monster that struck the town in 2008.

From the National Weather Service:

17-19

In 2017…a strong spring storm dropped across the Great Basin… and then moved eastward across Colorado. Isolated but strong thunderstorms preceded the system on the 17th with hail up to nickel size near Boulder Airport and Brighton. Significant snow fell across the Front Range mountains and foothills over the next couple of days. Along the Interstate 25 Corridor… rain turned to snow on the morning of the 18th…heaviest from around Broomfield northward. The heavy wet snow snapped the limbs of fully leaved trees and caused scattered power outages. A barns collapsed in northeast Loveland. Fifty-five head of cattle were inside the collapsed barn; three were injured and later euthanized. Numerous branches and trees snapped in the foothills. Elsewhere…several scattered smaller power outages were reported. Three to nearly five inches of liquid precipitation occurred…as rain or a mix of rain and snow…fell around Greeley. Storm totals in the Front Range mountains and foothills included: 42.0 inches near Allenspark…41.5 inches near Ward…36 inches at Estes Park… 32 inches near Pinecliffe…30.5 inches northwest of Golden… 30 inches near Nederland…26 inches near Breckenridge…25 inches near Aspen Springs and Bear Lake State Park…14 inches at Aspen Springs…with 9.5 inches near Evergreen. On the west side of the Interstate 25 Corridor…storm totals included: 10 inches near Superior and Louisville…6 to 8 inches in and around Fort Collins…6 inches in Lafayette… 5 inches in Broomfield and Loveland…and 4 inches near Niwot.

18-19

In 2011…a severe thunderstorm in central Adams County produced large hail and heavy rainfall on the 18th. Large hail from 1 inch to 1 3/4 inches in diameter…was reported in Commerce City…2 miles south-southeast of federal heights…Northglenn…and 2 miles south of Thornton.

In Commerce City…the storm uprooted trees and knocked out power lines. A carport was lifted off the ground and struck the power lines overhead. Heavy rain…from 1.0 to 1.5 inches fell in less than 2 hours in Commerce City and near Brighton. The combination of hail and strong winds broke windows in Northglenn.

In the foothills…moderate to heavy snow showers developed overnight. Storm totals included: 10.5 inches at Gold Hill…9.5 inches…3 miles west of Jamestown; 9 inches at Lake Eldora; with 6 inches… 11 miles southwest of Gilpin and 4 miles east-northeast of Nederland. At Denver International Airport…total rainfall over the 2-day period totaled 1.71 inches.

In addition…a peak wind gust to 37 mph was recorded on the 18th.

18-20

In 1915…3.9 inches of snow fell in the city. The estimated amount of snow that melted as it fell was 6.2 inches which would have totaled an estimated 10.1 inches of snowfall. Precipitation totaled 1.03 inches. North winds were sustained to 32 mph on the 18th. Low temperatures dipped to 25 degrees on both the 18th and 20th…establishing record minimums for both dates.

In 1988…prolonged heavy rainfall drenched metro Denver. The event began when heavy thunderstorms on the 18th caused some street flooding and power outages…followed by steady rain on the 19th and 20th. Rain amounts across metro Denver totaled 3 to 4 inches. Rainfall totaled 3.71 inches at Stapleton International Airport where north winds gusted to 39 mph on the 20th. Four to eight inches of snow fell in the foothills above 7 thousand feet.

18-26

In 2023…smoke and haze from massive wildfires in Canada significantly impacted air quality and visibility across Denver and the rest of northeast Colorado.

19

In 1927…southeast winds were sustained to 40 mph with gusts to 44 mph.

In 1956…a thunderstorm wind gust to 54 mph was recorded at Stapleton International Airport.

In 1969…hail stones to 1 inch in diameter were measured in Arvada and Aurora. Some minor damage was reported. Pea to marble size hail fell in Westminster.

In 1972…a tornado was reported by aircraft about 5 to 10 miles east of Parker.

In 1988…lightning started a fire at a house in the Denver suburb of greenwood village…causing 2 thousand dollars in damage.

In 1991…strong thunderstorms over east metro Denver produced wind gusts of 56 to 60 mph. The strong winds downed power lines…trees…and fences at some locations in Aurora. Thunderstorm outflow winds gusted to 60 mph at Stapleton International Airport.

In 1994…severe thunderstorms rumbled across metro Denver. The storms produced wind gusts averaging 65 mph and hail up to dime size. Wind gusts to 77 mph were recorded in Brighton. Numerous trees and power poles were downed by the winds. One power pole fell onto spectators at a high school graduation ceremony in Commerce City…injuring 6 people. In Fort Lupton…trees fell onto 2 parked cars… Knocking out the windshields. Hail to 3/4 inch in diameter was reported in Littleton. A thunderstorm wind gust to 52 mph was recorded at Stapleton International Airport.

In 1995…a slow moving tornado…which was mainly discernible by its dust and debris cloud…was spotted 2 miles northeast of Denver International Airport or about 10 miles northwest of Bennett. No damage was reported.

In 2007…lightning struck a 33-ft statue of Jesus at Mother Cabrini Shrine…in the foothills west of Golden. The blast broke off one of the statue’s arms and a hand…and also damaged a foot. It cost an estimated $200000 to repair.

In 2009…lightning struck the roof of a residence in Highlands Ranch. The home was not a total loss…but the fire caused extensive damage.

In 2010…a thunderstorm produced hail up to 7/8 inch in diameter in Thornton.

19-20

In 1864…a devastating major flash flood occurred on the normally dry and sandy Cherry Creek in Denver. The flood was caused by heavy thunderstorm rainfall and hail over the palmer ridge to the south of the city in both the Cherry Creek and plum creek basins. Nineteen deaths occurred along the South Platte River and Cherry Creek in Denver. The torrent swept cattle and sheep along with large trees and houses before it washing out several bridges…and moving large structures from their foundations. All city records were destroyed when city hall washed away. The rocky mountain news building…built on stilts in the middle of the creek…was totally destroyed by the raging waters…which were as deep as 5 feet on the morning of the 20th. Once the flood waters receded…much sand and gravel was left behind. Property damage from the flood was estimated at nearly one million dollars. This was the first major flood of record in the city.

20

In 1874…after a light late afternoon shower…3 rainbows were visible in the eastern sky. The two upper bows were of the usual colors. The lower bow had a deep violet center with a faint yellow and white rim.

In 1892…apparent post-frontal north winds were sustained to 40 mph with gusts to 48 mph. A trace of snow was the last snowfall of the season.

In 1899…snow pellets from 1/4 to 3/8 inch in diameter fell from a thundershower during the late afternoon. West winds were sustained to 42 mph with gusts as high as 48 mph.

In 1904…southeast winds were sustained to 40 mph with an extreme velocity of 42 mph produced by a thunderstorm.

In 1961…a tornado tore through central Douglas County…1 1/2 miles north of Castle Rock. The storm struck 2 ranches and the property of a drilling company. A car on the highway was lifted off the road and slammed into a truck…injuring the two occupants.

In 1983…heavy rain fell in Aurora with 1.00 to 1.50 inches of precipitation. Local flooding occurred in Lakewood.

In 1990…1 inch diameter hail fell at Buckley Field in Aurora. Minor damage was reported to autos…buildings and signs.

In 1995…hail as large as 3/4 inch in diameter fell near Bennett where a funnel cloud was sighted.

In 2001…damaging winds developed behind a vigorous cold front that moved south from Wyoming into metro Denver. High winds…gusting to 58 mph at Denver International Airport…downed trees and power lines and kicked up blowing dust…dirt…and debris…reducing the visibility to near zero at times. The poor visibility caused a multi-vehicle accident along U.S. Highway 85 north of Fort Lupton. Six people were treated for minor injuries. Several vehicles… Including semi-trailers…were blown off I-70 east of Denver. About 32 thousand Xcel Energy customers in metro Denver were without electricity for up to 2 hours. At least a dozen incoming flights at Denver International Airport were diverted to other airports. All departing flights were grounded for at least an hour. At Southwest Plaza…shoppers were evacuated as rocks holding a tarp on a portion of a roof under repair toppled into the mall. After the passage of the cold front…temperatures plunged from the lower 70’s to the mid 30’s in one hour as light snow developed. Heavy snow developed in the foothills during the evening. Peak wind reports included 68 mph near Parker and 63 mph near Sedalia. Snowfall totals included: 7 inches near Blackhawk… At Ken Caryl Ranch…and near Sedalia; 6 inches in Coal Creek Canyon…at Eldorado Springs…and atop Lookout Mountain; 5 inches at Chief Hosa…in Louisville…Rollinsville…and Wheat Ridge; and 4 inches in Aurora…Bailey…Parker…Castle Rock and near Morrison. Low temperature of 31 degrees during the early morning of the 21st equaled the record low for the date last set in 1931.

In 2004…severe thunderstorms produced hail as large as 1.25 inches near Ft. Lupton and hail to 1.50 inches 10 miles north of Ft. Lupton.

In 2014…severe thunderstorm produced hail…from 1 to 1 1/4 inches in diameter…across parts of Aurora…Denver… Englewood and Lakewood.

Continue reading May 19 to May 25: This Week in Denver Weather History →

Weather History

May 12 to May 18: This Week in Denver Weather History

Leave a comment

This Week in Denver Weather History

The snow is gone (for now?) but as our look back at this week in Denver weather history shows, it could return. That however is unlikely and more typical spring severe weather is far more common.

From the National Weather Service:

10-12

In 2011…a spring snowstorm brought heavy snow to the Front Range foothills and Palmer Divide. Storm totals included: 18 inches…4 miles south-southeast of Pinecliffe; 16 inches in Coal Creek Canyon; 15 inches…4 miles west-southwest of Eldorado Springs; 13 inches at Gold Hill…12 inches…4 miles west-southwest of Conifer and 4 miles northwest of Elizabeth; 11.5 inches…6 miles southwest of Evergreen and 4 miles east-northeast of Nederland; 11 inches…3 miles east of Jamestown and 10.5 inches…3 miles east of Franktown and 3 miles south of Golden and 10 inches…10 miles north of Elizabeth. At Denver International Airport… 1 inch of snowfall was observed.

In 2023…a slow moving storm system produced a period of moderate to heavy rainfall across the urban corridor…Palmer Divide and adjacent plains. A 24-hr daily record of 2.92 inches occurred at Denver International Airport on the 11th…with a 2-day total of 3.75 inches on the 11-12th…and 3-day total of 4.40 inches from the 10-12th. The prolonged period of rainfall resulted in flooding…flash flooding and washed out roadways… including Cherry Creek State Park and the National Wildlife Refuge at the Rocky Mountain Arsenal. Three-day rainfall amounts south and southeast of Denver ranged from 4.00 to 7.00 inches. In the Front Range west of Denver…above 10 thousand feet…heavy wet snowfall ranged from 1 to 2 feet. The 3-day event propelled Denver into 4th place for rainfall in month of May…with a total of 5.53 inches.

11-12

In 2014…from the 11th to the 12th…a strong storm system moved from southwest Colorado and produced heavy snow in and near the Front Range Foothills and metro Denver.  The snow was heaviest in the foothills where up to 2 1/2 feet of snow was observed. In the foothills…storm totals included: 30 inches near Pinecliffe; 29 inches… 8 miles northeast of Four Corners; 28 inches near Pingree Park; 27 inches near Allenspark; 20.5 inches near Idaho Springs; 19.5 inches at Gold Hill; 19 inches near Genesee; 18 inches near Blackhawk; 17 inches at Aspen Springs; 16.5 inches near Ward; 13.5 inches at Bergen Park; with 11 inches at Evergreen.  Along Urban Corridor and Palmer Divide…storm totals included: 10.5 inches at Eldorado Springs; 10 inches at Ken Caryl; 9 inches at Superior; 8 inches near Morrison; 7.5 inches in Broomfield and Highlands Ranch; 7 inches in Denver… near Franktown…Golden…Lakewood and Highlands Ranch; 6 inches…5 miles northeast of Westminster…7 miles south of Lyons and near Parker; with 5.5 inches at Aurora. At Denver International Airport…1.1 inches of snowfall was observed… along with 0.9 inches of water.

In 2023…a slow moving storm system produced a period of moderate to heavy rainfall across the urban corridor…Palmer Divide and adjacent plains. A 24-hr daily record of 2.92 inches occurred at Denver International Airport on the 11th…with a 2-day total of 3.75 inches on the 11-12th. The prolonged period of rainfall resulted in flooding…flash flooding and washed out roadways; including Cherry Creek State Park and the National Wildlife Refuge at the Rocky Mountain Arsenal.

12

In 1875…two forest fires on the eastern slope of the foothills were visible from the city.

In 1904…north winds were sustained to 40 mph with gusts to 48 mph.

In 1950…brilliant and complete primary and secondary rainbows arching across the sky were observed from Stapleton Airport.

In 1951…a wind gust to 51 mph was recorded at Stapleton Airport.

In 1984…winds gusted to 69 mph in Boulder. Northwest winds gusted to 47 mph at Stapleton International Airport.

In 1987…a small weak tornado touched down for about 2 minutes in southeast Denver. The twister hit a car dealership…blowing about a dozen windows out of cars and shattering four skylights on the building. Some tin roofing was blown off a patio a block and a half away. The tornado also downed a power pole. Damage at the dealership was estimated at 10 thousand dollars. A man was slightly injured by lightning in northwest Aurora.

In 1995…several funnel clouds were sighted near Parker. One of the funnels produced a short-lived debris cloud on the ground in an open field. No damage was reported.

In 2015…a man suffered minor injuries when the tree he took shelter under was struck by lightning. He was jogging at City Park Golf Course when the incident occurred. The jogger was taken to the hospital for observation.

12-13

In 1907…the temperature warmed to a high of 73 degrees on the 12th…before a cold front produced a thunderstorm… Northeast winds sustained to 40 mph…and rain changing to light snow overnight. Snowfall totaled only 2 inches…but the high temperature on the 13th was only 39 degrees.

In 1961…a storm that covered metro Denver with rain and snow started as thunderstorms on the evening of the 12th. Hail to 1 1/2 inches in diameter was reported 10 miles northwest of Stapleton Airport. Rain continued overnight and changed to snow on the 13th. Snowfall totaled 6.4 inches and precipitation (rain and melted snow) 1.96 inches at Stapleton Airport where north winds gusted to 39 mph. The rain and heavy wet snow caused icing damage to utility lines. Heavy snow occurred in the foothills.

In 1982…a major storm dumped 1.50 to 3.50 inches of rain across northeast Colorado and deposited prodigious amounts of snow in the foothills. Coal Creek Canyon southwest of Boulder was buried under 46 inches of snow with 39 inches at Nederland. The heavy wet snow downed many power lines in the foothills. In Thornton…the roof of a school was damaged by water from the heavy rain. At Stapleton International Airport…1.49 inches of rain were measured over the two day period. The heavy rain ended a severe and prolonged drought.

In 2004…a winter storm produced heavy snow in excess of a foot in the foothills above 6 thousand feet while heavy rain fell across the city. The heaviest snow occurred in the high country of Boulder County. Storm total snowfall was 14.5 inches near Jamestown. Rainfall totaled 0.81 inch at Denver International Airport with 0.94 inch recorded at Denver Stapleton. A trace of snow was recorded at both locations. East winds gusted to 24 mph at Denver International Airport on the 12th.

13

In 1905…a thunderstorm produced hail during the late afternoon. Precipitation totaled 0.57 inch.

13-14

In 1912…heavy snowfall totaled 12.4 inches over the city. Most of the snow…9.9 inches…fell on the 13th…which was the greatest 24 hour snowfall in May at the time. This was the last snowfall of the season. The low temperature dipped to 27 degrees on the morning of the 14th.

In 1989…a spring storm brought heavy rain and snow to the foothills. Metro Denver was soaked with 1 to 2 inches of rain. Rainfall totaled 1.26 inches at Stapleton International Airport.

In the foothills…Echo Lake received 20 inches of snow. A 30-ton Boulder slid onto I-70 east of the Eisenhower Tunnel…closing the freeway for 2 hours.

14

In 1910…a thunderstorm produced strong winds during the afternoon. Northwest winds were sustained to 42 mph.

In 1913…light moist snow and light hail fell during short intervals…although no thunder was heard. The trace of snowfall was the only snow of the month. Precipitation… Mostly rain…totaled 0.44 inch.

In 1984…a pilot reported a tornado 16 miles east of Stapleton International Airport. No damage was reported. A thunderstorm produced a 58 mph wind gust in Brighton. Thunderstorm winds gusted to 48 mph at Stapleton International Airport.

In 1989…lightning struck a home in Evergreen…setting it afire.

In 1992…strong thunderstorm winds of unknown velocity… Knocked over and damaged the infield tote board at Arapahoe park racetrack just southeast of Aurora. Damage was estimated at 200 thousand dollars. No injuries were reported. Lightning started two house fires…causing 35 hundred dollars in damage in Adams County just 9 miles north-northwest of Denver.

In 1994…a sudden wind gust…estimated at 40 mph…blew a portion of the roof off a shopping center in Lafayette. The roof also damaged two parked cars in an adjacent lot.

In 2001…a construction worker in Castle Rock received minor injuries when lightning struck close-by.

In 2002…a microburst wind gust to 53 mph was recorded at Denver International Airport.

In 2007…severe thunderstorms producing large hail…very heavy rain…and tornadoes impacted the urban corridor and adjacent plains. Heavy rain associated with a severe thunderstorm caused flooding along a small tributary draining into the South Platte River. The incident took place at 13th and Decatur St….near Invesco Field. The floodwaters inundated the bike trail adjacent to the creek. A woman with her child sought refuge under a bridge and became trapped by the high water. The woman slipped and the stroller containing the child was swept into the swift current. The child drowned. Rainfall totaled 0.42 inches at Denver International Airport. Elsewhere…golf ball hail was reported near Hudson. Hail…up to one inch in diameter…was observed in Boulder and Lyons. Thunderstorm wind gusts estimated to 70 mph were reported near Buckley Air Force Base…with a peak wind gust to 37 mph observed at Denver International Airport. A small tornado touched down near Ft. Lupton but did no damage.

14-15

In 1977…high winds up to 100 mph felled hundreds of trees in Gilpin County and caused extensive damage to telephone and power lines. Lumber and steel tanks were blown around in Boulder canyon. West winds gusted to 46 mph at Stapleton International Airport on the 15th.

14-18

In 1996…a period of unusually warm weather resulted in 4 record maximum temperatures in 5 days. The record high temperatures were 87 degrees on the 14th…89 degrees on the 15th…and 93 degrees on both the 16th and 18th. The temperature climbed to only 81 degrees on the 17th which was not a record.

Continue reading May 12 to May 18: This Week in Denver Weather History →

Climatology, Thornton Weather

April 2024 weather recap: Month sees above normal temps and precipitation

Thornton, Colorado's April 2024 Temperature Summary. (ThorntonWeather.com)
Thornton, Colorado’s April 2024 Temperature Summary. (ThorntonWeather.com)

The month of April was one that did not bring too much drama. While we did see warmer than normal temperatures and a good bit of precipitation, only one snowstorm was particularly notable.

The month started off with some rain on the first and then we entered a dry, mild period. From the second to the 15th, no precipitation was recorded and high temperatures were above average every day of the period.

On the 16th things became more unsettled with some wind and rain. Then, from the 19th and 20th, a spring snowstorm arrived. Thornton received 5.1 inches over the period while Denver bested us with 6.3 inches.

We then saw a few days of dry weather followed by a moisture-laden system that dropped more than an inch of rain on us from the 26th to the 28th.

For the month of April, Thornton’s average temperature came in at 52.1 degrees. This is well above our 18-year running average for April of 48.4 degrees. Temperatures ranged from a high of 82.7 degrees on the 14th down to a low of 28.5 degrees on the 2nd.

For Denver, at Denver International Airport where the Mile High City’s official records are taken, they too saw above normal temperatures. The average temperature for the month there came in at 50.5 degrees versus their long-term April average of 47.8 degrees.

In terms of precipitation, Thornton netted a very respectable 2.54 inches in the bucket. That was a good bit above our running average for the month of 1.74 inches.

Out at the airport, Denver received even more with 3.28 inches recorded. That is well above the Mile High City’s April average of 1.68 inches.

With only one snow event, Thornton’s total for the month came in below average at 5.1 inches. This, in comparison to our 18-year running average for the month of 6.4 inches.

Denver bested us on snowfall as well with 6.3 inches versus their long-term average for April of 6.1 inches.

Click here to view Thornton’s complete April 2024 climate summary report.

Thornton, Colorado's April 2024 Precipitation Summary. (ThorntonWeather.com)
(ThorntonWeather.com)
Weather History

May 5 to May 11: This Week in Denver Weather History

Leave a comment

This Week in Denver Weather History

This time of year the focus is usually on spring severe weather with lightning, tornadoes and hail being the highlight. Our look back at this week in Denver weather history shows many of those types of events. Also notable are the few, unusually late in the season snow events, some of which were quite heavy.

From the National Weather Service:

1-5

In 1898…snowfall totaled 15.5 inches in downtown Denver. Most of the snow…6.2 inches…fell on the 3rd. Most of the snow melted as it fell. The greatest snow depth on the ground was only 2.5 inches on the 3rd at 8:00 pm. This was the only snowfall during the month. Northeast winds were sustained to 22 mph on the 1st.

2-5

In 2001…a very slow moving pacific storm system became parked near the four corners region…which allowed heavy snow to develop above 6500 feet in the foothills with a mix of rain and snow over lower elevations of metro Denver. Snowfall totals included: 21 inches atop Crow Hill and at Idaho Springs; 19 inches near Blackhawk; and 18 inches in Coal Creek Canyon…Genesee…and 11 miles southwest of Morrison. Snowfall totaled 6.2 inches at the site of the former Stapleton International Airport. Precipitation (rain and melted snow) totaled 2.09 inches at Denver International Airport where north winds gusted to 30 mph on the 2nd.

3-5

In 1908…rain changed to snow on the evening of the 3rd and continued through the early evening of the 5th. Snowfall totaled 10.0 inches over downtown Denver. This was the last measurable snow of the season. Precipitation totaled 1.51 inches. North winds were sustained to 23 mph on the 3rd…33 mph on the 4th…and 21 mph on the 5th. Three temperature records were set. High temperatures of 30 degrees on the 4th and 38 degrees on the 5th were record low maximum temperatures for the dates. The reading on the 4th was also the all-time record low maximum for the month of May.

In 2007…a slow moving pacific storm system…from the desert southwest…brought a period of unsettled weather to the region. During the 3-day period…locally heavy snow was reported over parts of the Front Range foothills. Storm totals included: 15 inches near Conifer…14.5 inches west of Jamestown…13.5 inches; 6 miles southwest of Evergreen…and 12.5 inches at pine junction. Severe thunderstorms…producing large hail…up to one inch in diameter were observed in the vicinity of Boulder and Hudson. Lightning struck a residence in Jefferson County. The roof was hit…causing the attic to catch fire. At Denver International Airport…lightning struck a United Airlines jet as it was pushing away from the gate. The passengers were taken off the jet and put on another plane.

4-5

In 1986…high winds buffeted the foothills. Wind speeds of 60 to 75 mph were recorded in Boulder. At Stapleton International Airport…west winds gusted to 45 mph on the 4th and to 40 mph on the 5th.

In 2000…a brief warm spell resulted in setting two daily high temperature records. The temperature climbed to highs of 87 degrees on the 4th and 89 degrees on the 5th.

4-8

In 1969…heavy rains caused flooding on Boulder creek in Boulder…which resulted in one death on the 7th. Flooding also occurred on bear creek in Sheridan and on the South Platte River in Denver. Rain over most of the eastern foothills started late on the 4th and continued with only brief interruptions in many areas until the morning of the 8th. Very high rates of rainfall occurred on the 6th and 7th with the greatest intensities in a band along the foothills from about 25 miles southwest of Denver northward to Estes Park. Storm totals by both official and unofficial measurements exceeded 10 inches over much of this area and were over 12 inches in some localities. Heavy snow fell in the higher mountains and in the foothills later in the period. The saturation of the soil resulted in numerous rock and landslides…and the heavy run-off caused severe damage along many streams and flooding on the South Platte River. Many foothill communities were isolated as highways were blocked and communications disrupted. Roads were severely damaged over a wide area…and a large number of bridges washed out. Many roads were closed due to the danger from falling rocks. A building in Georgetown collapsed from the weight of heavy wet snow. In Boulder…a man drowned when caught by the flooding waters of Boulder Creek…and a patrolman was injured. Rainfall totaled 7.60 inches in Boulder with 9.34 inches recorded at the Public Service Company electric plant in Boulder Canyon. In Morrison…rainfall totaled 11.27 inches in 4 days. Heavy rainfall totaled 4.68 inches at Stapleton International Airport over 3 days from the 5th through the 7th. Rainfall of 3.14 inches was recorded in 24 hours on the 6th and 7th. Downstream flooding continued along the South Platte River until the 12th when the flood crest reached the Nebraska line.

5

In 1903…apparent post-frontal northeast winds were sustained to 48 mph with gusts to 60 mph.

In 1950…a northwest wind gust to 52 mph was recorded at Stapleton Airport.

In 1969…a funnel cloud was observed for 2 to 3 minutes just north of Parker. Two other funnel clouds were sighted in the same area. The public sighted a tornado 15 miles east of Stapleton International Airport. No damage was reported.

5-6

In 1907…rain changed to snow on the 5th…continued through the night…and totaled 3.50 inches. Northeast winds were sustained to 15 mph on the 5th.

In 1917…post-frontal rain changed to heavy snow and totaled 12.5 inches over downtown Denver. Most of the snow… 12.0 inches…fell on the 5th and this was the greatest 24-hour snowfall ever measured during the month of May. This was also the only measurable snow of the month that year. Low temperatures of 27 degrees on the 5th and 23 degrees on the 6th were record minimums for the dates. High temperatures on both days were in the lower 40’s. Southeast winds were sustained to 24 mph with an extreme velocity to 26 mph.

In 1964…high winds gusted to 54 mph in Boulder and to 80 mph at Jefferson County Airport near Broomfield. Wind gusts of 50 to 60 mph were common over all of eastern Colorado. Buildings…power lines…trees…and vehicles were damaged by the wind. South-southwest wind gusts to 54 mph caused some blowing dust at Stapleton International Airport where the visibility was briefly reduced to 2 miles.

In 1973…a heavy driving rain storm with embedded thunderstorms…produced 1 to 5 inches of rain and caused local flash flooding along the east slopes of the Front Range. The greatest flash flooding occurred in metro Denver where rainfall totaled 3.56 inches at Stapleton International Airport. Flooding in metro Denver occurred on Clear Creek and the South Platte River…already swollen from heavy snowmelt. Numerous basements were flooded… Roads and streets were washed out…a bridge was demolished… And miscellaneous other damage was reported. North winds gusted to 39 mph at Stapleton International Airport during the storm. The storm produced major downstream flooding along the South Platte River all the way to the Nebraska border during the next two weeks. One person died and total damage was estimated at around 120 million dollars.

In 1978…heavy wet snow of around 24 inches collapsed an office and hotel building in Boulder. Many cars were abandoned in the city. Denver received 14 inches of heavy wet snow with Evergreen and Golden reporting 12 inches. Snowfall totaled 12.4 inches at Stapleton International Airport with a total accumulation of snow on the ground of 8 inches due to melting. Southeast winds gusted to 23 mph on the 5th. Temperatures both days remained in the lower to mid-30’s.

6 Continue reading May 5 to May 11: This Week in Denver Weather History →

Climatology, Thornton Weather

Thornton’s May 2024 preview: From snow to severe storms

Thornton, Colorado May weather preview.
Thornton, Colorado May weather preview.

Colorado’s famously highly variable weather seems to showcase itself during the month of May when a variety of weather conditions can be seen.

The month can certainly bring extremes.

Snow is not entirely uncommon during the month, oftentimes causing damage to newly bloomed trees.

More common however is severe weather, particularly in the latter half of the month.  Thunderstorms become more frequent and their associated hazards – lightning, wind, hail and tornadoes – are usual visitors.

For a complete look at what lies ahead for the month of May, check out our full preview here.

Weather, natural disasters & climate news and information.