Thornton saw overall weather conditions not too far out of line with what we expect for the month of May. Temperatures were a good bit below normal however while precipitation came in right near average.
The month started out a bit chilly and we received our first and only snow for the month on the first. Warmer weather returned right away though and lasted until the 7th of the month when severe weather arrived to the Colorado plains. Tornadoes and large hail were seen to our east and northeast but we received only a bit of rain and some small hail.
Cooler weather conditions lasted for a few days before we warmed up for two days on the 12th and 13th. That was short-lived however and once again things cooled down quite a bit with the 16th and 17th of the month seeing high temperatures only in the mid to upper 40s and a healthy shot of rain.
The final 11 days of the month saw temperatures near or above normal for the most part. Stormy weather returned on the 24th as afternoon thunderstorms brought marble sized hail to Thornton. Eastern Adams County and Washington County saw tornadoes and large, damaging hail. Six of those last 11 days of the month did bring measurable precipitation.
Thornton saw a monthly average temperature of 54.2 degrees. This was well below Denver’s 30 year average for the month of May of 57.1 degrees. Out at DIA where Denver’s official measurements are taken, the Mile High City was similarly cool with a monthly average of 54.4 degrees.
Temperatures in Thornton ranged from a high of 85.6 degrees on the 21st down to a below freezing low of 24.9 degrees on the 2nd. Out at the airport, the warmest reading was 83 degrees and the lowest 28 degrees, both on the same dates as our warmest / coldest temperatures.
In terms of precipitation, Denver averages 2.12 inches during the month of May. Thornton saw 2.07 inches in our rain bucket while DIA recorded 2.38 inches.
The only snow during May 2016 in Thornton came on the first of the month when 0.3 inches fell. Denver officially recorded only a trace. Average snowfall for the month of May in Denver is 1.1 inches.
May 2016 temperature summary for Thornton, Colorado. (ThorntonWeather.com)May 2016 precipitation summary for Thornton, Colorado. (ThorntonWeather.com)
From the National Weather Service:
CLIMATE REPORT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
244 AM MDT WED JUN 1 2016
...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF MAY 2016...
CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2016
WEATHER OBSERVED NORMAL DEPART LAST YEAR`S
VALUE DATE(S) VALUE FROM VALUE DATE(S)
NORMAL
................................................................
TEMPERATURE (F)
RECORD
HIGH 95 05/26/1942
LOW 19 05/02/2013
05/03/1907
01/01/2000
HIGHEST 83 05/21 95 -12 85 05/31
LOWEST 28 05/02 19 9 27 05/10
05/09
AVG. MAXIMUM 66.9 71.5 -4.6 63.3
AVG. MINIMUM 41.9 42.7 -0.8 42.7
MEAN 54.4 57.1 -2.7 53.0
DAYS MAX >= 90 0 0.8 -0.8 0
DAYS MAX <= 32 0 0.0 0.0 0
DAYS MIN <= 32 3 1.9 1.1 3
DAYS MIN <= 0 0 0.0 0.0 0
PRECIPITATION (INCHES)
RECORD
MAXIMUM 8.57 1876
MINIMUM 0.06 1974
TOTALS 2.38 2.12 0.26 3.76
DAILY AVG. 0.08 0.07 0.01 0.12
DAYS >= .01 13 9.4 3.6 19
DAYS >= .10 4 4.8 -0.8 10
DAYS >= .50 1 1.2 -0.2 2
DAYS >= 1.00 1 0.2 0.8 1
GREATEST
24 HR. TOTAL 1.38 05/26 TO 05/27 05/08 TO 05/09
05/09 TO 05/09
SNOWFALL (INCHES)
RECORDS
TOTAL MM MM
TOTALS T 1.1
DEGREE_DAYS
HEATING TOTAL 326 265 61 367
SINCE 7/1 5556 5996 -440 5572
COOLING TOTAL 3 21 -18 4
SINCE 1/1 3 22 -19 4
FREEZE DATES
RECORD
EARLIEST 09/08/1962
LATEST 06/08/2007
EARLIEST 10/07
LATEST 05/05
..........................................................
WIND (MPH)
AVERAGE WIND SPEED 10.2
RESULTANT WIND SPEED/DIRECTION 2/154
HIGHEST WIND SPEED/DIRECTION 39/200 DATE 05/08
HIGHEST GUST SPEED/DIRECTION 47/300 DATE 05/29
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
AVERAGE SKY COVER 0.60
NUMBER OF DAYS FAIR 4
NUMBER OF DAYS PC 18
NUMBER OF DAYS CLOUDY 9
AVERAGE RH (PERCENT) 60
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 13 MIXED PRECIP 0
HEAVY RAIN 1 RAIN 5
LIGHT RAIN 17 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 2
HEAVY SNOW 0 SNOW 1
LIGHT SNOW 1 SLEET 0
FOG 10 FOG W/VIS <= 1/4 MILE 2
HAZE 3
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
Springtime means not only is the weather active, so too is the wildlife. Great Horned Owl owlets in Thornton. (Shannon Dizmang)
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, 2016. 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.
[flickr_set id=”72157667503622900″]
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.
May 29 to June 4: This week in Denver weather history
There are many notable events on our look back at the weather history books for this week but one in particular stands out. It was 30 years ago this week, on June 3, that the infamous Thornton tornado struck. This twister still stands as the most damaging tornado to have ever struck the Denver metro area.
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.
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.
29-1
In 1894…heavy rain combined with snowmelt runoff caused widespread flooding over the South Platte River basin. Rainfall was heaviest in the foothills where 5 to 8 inches were measured over the 4 days. Heavy rainfall west of Boulder flooded mining towns and damaged mining properties. In the canyons above Boulder…railroads and roads were washed out along with many bridges. The floodwaters spread into central Boulder and covered a wide area from University Hill north to near Mapleton Hill to a maximum depth of 8 feet. Many houses were swept away…and every bridge in Boulder was destroyed. A few people…trapped in their homes by the floodwaters… Had to be rescued. However…the gradual rise of the flood waters resulted in only one death. Boulder creek spread to a width of nearly one mile in the pasture land to the east of Boulder. Extensive flooding on left hand creek north of Boulder washed away railroad and wagon bridges. The heavy cloudbursts caused flooding on bear creek…which washed away bridges…railroad tracks…and structures and destroyed the canyon roadway. Morrison sustained the heaviest flood damage on bear creek. In Denver…rainfall totaled only 1.50 inches on the 30th and 31st…but the heavy rainfall on upstream tributaries of the South Platte River caused the river to rise as much as 10 feet above the low water mark in the city…which caused some flooding of pasture land downstream to a depth of 6 feet near Brighton.
30
In 1875…a windstorm lasting almost all day produced sustained winds to 42 mph.
In 1935…southeast winds sustained to 29 mph with gusts to 34 mph produced a moderate duststorm during the afternoon.
In 1938…heavy thunderstorm rain and hail pummeled downtown Denver during the evening hours. Rainfall accumulated to 1.63 inches. Hail accumulated to a depth of 18 inches.
In 1948…a localized thunderstorm caused flooding on sand creek in Aurora and northeast Denver. Rainfall was only 0.49 inch in downtown Denver where light hail also fell.
In 1963…a golfer died of injuries received when struck by lightning on a golf course southwest of Denver. A warehouse in Denver was damaged and its contents destroyed by a lightning-caused fire.
In 1967…up to 4.00 inches of rain in Lakewood and wheat ridge caused flooding of roads and basements. Water was several feet deep in some yards. Many streets were temporarily closed. Hail as large as 1 inch in diameter fell in Wheat Ridge. Hail piled up to 2 feet deep in some low lying areas of east and southeast Denver. Snowplows were employed to remove the hail. Stapleton International Airport…where west winds gusted to 39 mph…received 1.51 inches of rain and hail…which forced the closure of the runways for an hour. Hail stones to 3/4 inch in diameter were measured at Buckley Field. A funnel cloud was sighted near south Wadsworth Blvd and Bear Creek. A tornado touched down briefly in the vicinity of 60th and 62nd avenues near north Washington Street. The storm uprooted trees and damaged one building. Doors were ripped from a business house…widely scattering irrigation pipe. In addition…a total of 3 funnel clouds were sighted in that area.
In 1970…hail up to 1 inch in diameter fell at Stapleton International Airport.
In 1976…a single thunderstorm crossed south metro Denver producing a funnel cloud 2 miles south of Arapahoe road and Broadway. The storm moved over Buckley Field producing a funnel cloud and 1/2 inch diameter hail. As the storm moved northeast of the city…a large tornado touched down near east 59th Ave and tower road and was on the ground for 20 minutes. It demolished a 60-foot-long cinderblock cow shed…tore a wall from a machinery shed…tore shingles off the roof of a farmhouse nearby…and felled 12 trees on one farm. A boy in a feed shed 20 feet from a destroyed building was not injured.
In 1977…3/4 to 1 inch diameter hail fell at or near Stapleton International Airport. One inch to baseball size hail fell in south Denver…damaging some homes and extensively damaging some airplanes at Arapahoe County airport…now centennial airport. Hail covered highways to a depth of 6 to 8 inches in south Denver.
In 1978…two funnel clouds were sighted 5 miles south of Stapleton International Airport. Hail up to 1 1/4 inches in diameter was reported in wheat ridge and northwest Denver. Only 1/2 inch diameter hail fell at Stapleton International Airport.
In 1989…golf ball size hail fell at the junction of I-25 and I-225. One inch diameter hail fell in Littleton.
In 1990…a line of severe thunderstorms crossed metro Denver… Producing wind gusts to 60 mph and scattered areas of pea to marble size hail. Small trees and branches were blown down by the strong thunderstorm winds…which also caused minor power outages across southern and eastern sections of metro Denver. The strong winds uprooted a 25- to 30-foot tree in the acres green subdivision of northern Douglas County. The tree blocked a busy street for several hours. A pilot reported hail as large as 1 1/2 inches in diameter covering the ground near the north end of a runway at Stapleton International Airport. Heavy rain caused a rock and mud slide that partially closed the Boulder canyon highway 10 miles west of Boulder. Thunderstorm winds gusted to 41 mph at Stapleton International Airport.
In 2001…lightning ignited a fire which destroyed a luxury home on bear mountain near Evergreen. Estimated damage was set at 1 million dollars.
In 2003…flash flooding occurred in the Hayman Fire burn area after as much as 1 inch of rain fell in 30 minutes. The heavy rainfall washed out many access roads and closed State Highway 67 between Deckers and west creek. A 3-foot wall of water ran down Fourmile Creek from the YMCA camp at Shady Brook…damaging one building in the camp and flooding roads. Hail as large as 3/4 inch in diameter fell near Roggen in weld County.
In 2005…lightning struck as least 20 homes in Westminster. Only minor damage was reported. Severe thunderstorms produced hail as large as 1.25 inches in and near Fort Lupton and hail to 3/4 inch near Indian Hills in Jefferson County.
In 2014…heavy rainfall…nearly 1.2 inches in 30 minutes… produced localized street flooding in Boulder. The heavy rain coupled with the already swollen creeks from the spring runoff along Boulder Creek resulted in the flooding. Street flooding was reported at 6th St and Canyon Blvd and at Baseline Road. Some cars were stranded in the high water in low lying areas and one person reported being trapped in his vehicle.
30-31
In 1935…heavy thunderstorm rains overnight caused flash flooding east of the city on both Kiowa and Bijou Creeks… Resulting in a total of 9 deaths. Most of the damage was on Kiowa Creek where there were more structures. The water rose rapidly during the storm…ripping houses and stores from their foundations and sweeping them downstream. Precipitation in Denver totaled only 0.01 inch. Hail fell in the city for a short time. The hail was very small and caused no damage.
In 1983…a late storm of rain and snow hit the Front Range. Over an inch of rain fell at some spots…and above 7 thousand feet…1 to 5 inches of snow whitened the ground. Some snowflakes even fell in the western suburbs of metro Denver on the night of the 30th.
In 2002…unseasonably warm weather at the end of the month resulted in 3 temperature records. High temperature of 91 degrees on the 30th equaled the record maximum for the date. Low temperature of 61 degrees on the 31st was a record high minimum for the date. High temperature of 93 degrees on the 31st was a record maximum for the date.
Damage from a May 24, 2016 tornado is seen on a farm near Platner, Colorado. (National Weather Service)
The thunder rolled across eastern Colorado on Tuesday, May 24 – as did hail, wind and tornadoes. Washington County saw the most intense activity with multiple twisters including one damaging tornado that has been rated an EF-1.
The National Weather Service sent survey teams to the area to evaluate the damage inflicted by Mother Nature.
They found two tornadoes of relatively weak EF-0 strength occurred near Akron. Neither any caused damage.
Near Platner though, a more powerful tornado ripped through a farm at about 6:50pm that evening. The twister lifted a pole barn, destroying it. Debris was found one mile away.
Wind and hail ripped across an area six miles wide near Akron causing extensive damage. Farm equipment was toppled and a barn heavily damaged by the wind while houses saw the siding punctured and windows broken from hail.
Below are images taken by the National Weather Service of the area.
[flickr_set id=”72157668536532282″]
Public Information Statement
National Weather Service Denver/Boulder CO
1056 AM MDT THU MAY 26 2016
...NWS DAMAGE SURVEY FOR 05/24/16 TORNADO EVENT...
.OVERVIEW...A long-lived supercell thunderstorm moved across
eastern Colorado and produced two EF-1 tornadoes and two EF-0
tornadoes in Washington County on May 24, 2016. Widespread wind
and hail damage also occurred, with a swath of damage nearly 6
miles wide at some points east and northeast of Akron.
.Washington County tornado near Platner...
Rating: EF-1
Estimated peak wind: 86-110 mph
Path length /Statute/: 0.9 miles
Path width /Maximum/: 20 yards
Fatalities: 0
Injuries: 0
Start date: May 24 2016
Start time: 650 PM MDT
Start location: 1 mile northeast of Platner / Washington County / CO
Start Lat/Lon: 40.1647 / -103.0467
End date: May 24 2016
End time: 655 PM MDT
End location: 1 mile east of Platner / Washington County / CO
End_lat/lon: 40.155 / -103.0366
This tornado struck one farm, lofting and completely destroying
a pole shed, and also damaging trees. Power lines were snapped
just to the southeast of the farm.
.Washington County tornado near Yuma County line...
Rating: EF-1
Estimated peak wind: 110 mph
Path length /Statute/: 0.1 mile
Path width /Maximum/: 90 yards
Fatalities: 0
Injuries: 0
Start date: May 24 2016
Start time: 715 PM MDT
Start location: 9 miles north/northwest of Yuma / Washington County / CO
Start Lat/Lon: 40.2350 / -102.7943
End date: May 24 2016
End time: 716 PM MDT
End location: 9 miles north/northwest of Yuma / Washington County / CO
End_lat/lon: 40.2348 / -102.7936
This tornado struck one farm, destroying a pole shed. Slight roof damage
occurred to the house, along with some tree damage.
.Washington County tornado 1 mile Northeast of Akron...
Rating: EF-0
Estimated peak wind: 65-85 mph
Path length /Statute/: 0.0 miles
Path width /Maximum/: 10 yards
Fatalities: 0
Injuries: 0
Start date: May 24 2016
Start time: 644 PM MDT
Start location: 1 mile southeast of Akron / Washington County / CO
Start Lat/Lon: 40.1490 / -103.1981
End date: May 24 2016
End time: 644 PM MDT
End location: 1 mile southeast of Akron / Washington County / CO
End_lat/lon: 40.1490 / -103.1981
Brief touchdown with no damage.
.Washington County tornado 1 mile Southeast of Akron...
Rating: EF-0
Estimated peak wind: 65-85 mph
Path length /Statute/: 0.0 miles
Path width /Maximum/: 10 yards
Fatalities: 0
Injuries: 0
Start date: May 24 2016
Start time: 647 PM MDT
Start location: 1 mile northeast of Akron / Washington County / CO
Start Lat/Lon: 40.1708 / -103.1959
End date: May 24 2016
End time: 647 PM MDT
End location: 1 mile northeast of Akron / Washington County / CO
End_lat/lon: 40.1708 / -103.1959
Brief touchdown with no damage.
EF Scale: The Enhanced Fujita Scale Classifies
Tornadoes into the following categories.
EF0...Weak...... 65 to 85 mph
EF1...Weak...... 86 to 110 mph
EF2...Strong.... 111 to 135 mph
EF3...Strong.... 136 to 165 mph
EF4...Violent... 166 To 200 mph
EF5...Violent... >200 mph*
NOTE:
The information in this statement is PRELIMINARY and subject to
change pending final review of the events and publication in
NWS Storm Data.
May 22 to May 28: This week in Denver weather history
If history is a teacher, our look back at this week in Denver weather history should provide great instruction on the dangers severe weather presents in our history. It was eight years ago this week that the infamous Windsor tornado tore through the area killing one man and damaging hundreds of homes.
From the National Weather Service:
20-22
In 1959…a three-day rain caused some flooding in metro Denver where rain totaled 1.68 inches at Stapleton Airport. Showers…accompanied by hail near Brighton…caused some damage to truck crops. Heavy snow in the foothills caused damage to power and telephone lines.
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.
21-22
In 1878…overnight heavy rains of cloudburst intensity on the Palmer Divide to the south of the city caused flash flooding on Cherry Creek in Denver…which resulted in 2 deaths. A wall of water swept through the city between 2:00 am and 3:00 am on the morning of the 22nd. The flood was so sudden and unexpected that homes along the creek in the city were submerged in water knee deep before the slumbering occupants knew anything about it. By daybreak the banks on both sides of the creek were lined by residents viewing the destruction caused by the raging waters in such a short time. Seven bridges across the creek were destroyed in the city. Damage to private and city property was estimated between 30 and 50 thousand dollars. Quite a number of cattle and sheep were killed along the reach of the creek. Only 0.01 inch of rain fell in the city on the 21st with a trace of rain on the 22nd. Flash flooding also occurred on Kiowa Creek near Bennett on the night of the 21st when the flood waters washed out the Kansas Pacific Railroad bridge. An east bound freight train plunged into the turbulent waters killing the three crewmen. The locomotive was completely buried in the sand and never found to this day!
21-23
In 1876…snow changed to heavy rain over the city…resulting in widespread flooding along Cherry Creek and the South Platte River…nearly as great as the flash flood of May 19-20…1864. However…damage was greater because the city had grown much larger and there were more bridges for the flood waters to destroy. Precipitation in the city totaled 6.70 inches from 10:00 pm on the 21st through 3:00 am on the 23rd. The greatest precipitation ever recorded in Denver in 24 hours…6.53 inches…occurred on the 21st and 22nd. Small buildings and bridges along Cherry Creek were washed away by the flood waters. Bridges over the South Platte River were damaged. The city irrigation ditch was damaged and rendered unfit for service. Strong winds at speeds of 30 to 40 mph drove the heavy rain through brick walls 12 to 16 inches thick. Many sheep and cattle were either killed by lightning or drowned…including some 100 head of cattle in Jefferson County alone. There was immense damage to railroad tracks…especially the Kansas Pacific line to the east of the city. The Colorado central suffered estimated damage of 10 to 15 thousand dollars. In addition…the heavy rain caused extensive flooding on soda and bear creeks in the foothills. Flooding along Boulder creek inundated farm and pasture land in the Boulder valley and damaged a few bridges. Rail travel had to be suspended in the area for several days.
22
In 1876…the most precipitation in Denver on any calendar day…6.50 inches…occurred.
In 1901…northeast winds were sustained to 41 mph with gusts to 45 mph.
In 1903…west winds were sustained to 45 mph with gusts to 55 mph from an apparent microburst…which produced a trace of rain.
In 1976…the public reported 3/4 inch diameter hail and wind gusts to 53 mph near Littleton.
In 1987…golf ball size hail fell in the Lorretto Heights area of south metro Denver.
In 1991…a tornado touched down briefly in Castle Rock. No injuries were reported.
In 1993…an off duty national weather service employee reported hail up to golf ball size just west of the city of Denver in Jefferson County. Thunderstorm wind gusts reached 58 mph at Jefferson County Airport near Broomfield and 33 mph at Stapleton International Airport.
In 1996…a severe thunderstorm pummeled northwest and northern sections of metro Denver with large hail ranging in size from 3/4 to 2 inches in diameter. The cities of Arvada and Westminster were the hardest hit. The insurance industry estimated 60 million dollars in damage to homes and personal property and 62 million dollars in damage to automobiles…for a total of 122 million dollars in insured losses. This estimate also included the cities of Golden… Thornton…and wheat ridge. This was the fourth worst hailstorm to hit metro Denver in the last 10 years.
In 1998…large hail fell across north metro Denver. Hail as large as 1 1/2 inches in diameter was measured in Broomfield and Hudson. Hail to 1 1/4 inches fell in Roggen. Hail to 1 inch fell in Brighton…near Keenesburg… In Watkins…and in the city of Denver. Lightning ignited a house fire in Ft. Lupton. A warehouse worker in Denver was injured when he was knocked off a loading dock by a lightning bolt. The bolt skipped off a nearby radio tower and struck him in the arm. He was treated for numbness in his right arm and released.
In 1999…severe thunderstorms produced 7/8 inch diameter hail over the city of Denver…with one inch diameter hail reported in Aurora…and 3/4 inch hail near Watkins.
In 2006…a lightning strike sparked a fire and damaged the roof of a recreation center in Evergreen. The fire spread into some brush and consumed about one quarter acre before it was extinguished. Severe thunderstorms produced strong wind gusts across portions of metro Denver. Winds gusted to 72 mph in Georgetown…62 mph near Parker and Bennett… 60 mph in Castle Rock…and 59 mph in Longmont. The winds caused no reportable damage. A thunderstorm produced southwest wind gusts to 52 mph at Denver International Airport.
In 2008…a powerful tornado swept north-northwestward across Weld County…carving a path of destruction nearly 39 miles in length. The tornado…up to one-mile wide at times… Initially touched down northeast of Platteville and finally lifted 6 miles west-northwest of wellington. A tornado assessment in the aftermath of the tornado revealed extensive areas of damage. On the Enhanced Fujita Scale… There were pockets of ef3 damage near the Missile Silo Park campground and to businesses and a home in eastern Windsor. Farmers reported extensive damage to crops and irrigation equipment. There was one fatality and 78 injuries… Ranging from broken bones to minor cuts and lacerations. One man was killed when he tried to escape a trailer park in his motor home. Tractor trailers were flipped along U.S. Highway 85…and over 200 power poles were snapped or blown down. Approximately 60000 people were left without electricity. The tornado overturned 15 railroad cars and destroyed a lumber car. The tornado also flattened the main feedlot in Windsor and destroyed a dairy barn. Most of the 400 cows were killed in the tornado or destroyed later. The thunderstorm also produced hail up to the size of baseballs. Another tornado from a separate thunderstorm… Rated an ef1…briefly touched down near Dacono and destroyed 5 buildings. The tornado overturned a five-wheel trailer and injured a man sitting inside. Preliminary estimates from FEMA indicated 850 homes were damaged…and nearly 300 homes were significantly damaged or destroyed. The Poudre Valley Rural Electric Associated reported $1 million of damage to electric transmission lines. Privately insured damages totaled $147 million…making it the state’s 4th costliest disaster. Large hail up to 1 1/2 inches in diameter…was reported in the vicinities of Golden and Longmont.
In 2014…a severe thunderstorm Denver area produced nickel to quarter size hail in parts of west Denver and near Bennett. Locally heavy rainfall produced some minor street flooding in parts of metro Denver. The heavy rainfall produced localized flash flooding near Bennett. Rainfall totaled 0.54 inches at Denver International Airport.
22-23
In 1933…high winds and gales overnight caused considerable damage in and near the city. Much greenhouse glass was broken…which caused damage to sheltered plants. Great numbers of plants growing in the open were damaged or killed by wind-driven sand and soil. Fields were eroded by the wind and a few trees were uprooted. West winds were sustained to 38 mph with gusts as high as 65 mph in downtown Denver on the 22nd.
23
In 1916…southeast winds were sustained to 43 mph with gusts as high as 52 mph. The winds were strong for several hours during the afternoon.
In 1965…thunderstorm outflow wind gusts to 59 mph were recorded at Stapleton International Airport.
In 1987…slow moving thunderstorms bombarded metro Denver. One inch diameter hail was reported in south central Denver. Torrential rain caused widespread street flooding… Stalling traffic throughout the area. Rainfall totaled 2.10 inches in just 25 minutes in extreme southeast Aurora. Many other locations in Aurora and east Denver reported 1 to 1 1/2 inches of rain in about 30 minutes. Thunderstorm rainfall totaled 1.33 inches at Stapleton International Airport where 1/4 inch diameter hail was measured and north winds gusted to 40 mph. A man was slightly injured by lightning near Stapleton International Airport. Lightning also started a fire that severely damaged a house in Aurora.
In 1990…a microburst wind gust to 52 mph at Stapleton International Airport produced some blowing dust.
In 1991…thunderstorms moving from southwestern sections of metro Denver to the east of Denver produced large hail up to golf ball size. An estimated 5 thousand homes and 8 thousand cars received considerable damage. Early estimates placed damage costs around 60 million dollars. Three funnel clouds were also reported…two by personnel at Buckley Field and the other by a storm spotter. Heavy rain produced street flooding in Aurora where hail accumulated to a depth of 6 inches. As the storms moved to the east…golf ball size hail was reported at Strasburg.
In 1997…hail to 3/4 inch diameter fell in Broomfield.
In 2002…a very strong microburst near Strasburg swept a woman into a swirl of dirt and carried her about 150 feet. The woman was in an open field…corralling a yearling horse… When the incident occurred. Fortunately…she received only minor injuries.
May 15 to May 21: This Week in Denver Weather History
Springtime in Denver brings a variety of weather and flooding becomes a very real threat. In our look back at this week in Denver weather history we see many such events including one in 1864 that killed 19 people and destroyed the Rocky Mountain News building.
From the National Weather Service:
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.
15
In 1894…southwest winds were sustained to 38 mph with gusts to 50 mph.
In 1910…an apparent cold front produced sustained northeast winds to 48 mph.
In 1986…a thunderstorm dumped an inch of rain in an hour over the eastern part of Aurora. Total rainfall from the storm was 1.62 inches.
In 1989…a 47 year old man…a Lakewood police officer…was struck and injured by lightning. Small hail piled up 3 to 4 inches deep near Golden. There was reported street flooding from heavy thunderstorm rains over western metro Denver. Rainfall totaled 0.76 inch at Stapleton International Airport.
In 1990…a thunderstorm produced a wind gust to 69 mph at Jefferson County Airport in Broomfield. Thunderstorm winds gusting to 49 mph at Stapleton International Airport produced some blowing dust.
In 1991…a funnel cloud was sighted near Morrison. Later… Hail up to 2 inches deep covered U.S. Highway 285 at South Turkey Creek Road in west metro Denver. Baseball size hail was reported on the east side of Littleton. Dime size hail was reported in Boulder.
In 1993…lightning started a fire which damaged a home in Boulder. No one was injured.
In 1997…a wind gust to 58 mph was recorded at the site of the former Stapleton International Airport. A street sign was blown down at the Havana Street exit along I-70.
In 1999…lightning ignited a small fire in a 3-story structure in sunshine canyon above Boulder. The fire was quickly extinguished and caused only minor damage.
In 2003…thunderstorms produced very heavy rainfall and localized flash flooding in the foothills of central Boulder County. Rainfall ranged from 1.5 to 2.5 inches in less than 2 hours. Water ranging in depth from 6 to 9 inches covered State Highway 119 in Boulder Canyon. Dirt and rocks also washed over the roadway. Some basements were flooded in the sugarloaf area. Rockslides were also reported at Boulder falls…Lefthand Canyon…and Fourmile Canyon.
15-16
In 1957…heavy snowfall totaled 8.8 inches at Stapleton Airport. The greatest amount on the ground was 3 inches.
In 1986…a spring storm dumped 1 to 2 inches of rain over metro Denver…but 2.71 inches fell at Buckley Field in Aurora. Rainfall only totaled 0.84 inch at Stapleton International Airport. Snow fell in the foothills with 7 inches recorded in Coal Creek Canyon southwest of Boulder.
16
In 1875…a heavy hail storm turned into heavy rain during the afternoon. Rainfall totaled 0.86 inch in just 37 minutes…while the temperature dropped 22 degrees in 22 minutes. Precipitation totaled 0.90 inch.
In 1894…west winds were sustained to 48 mph with gusts to 56 mph.
In 1949…a tornado was observed for 16 minutes…20 miles to the southeast of Stapleton Airport. The tornado moved 5 miles to the northeast before dissipating. No damage was reported.
In 1963…intense lightning started several forest fires in the foothills southwest of Denver near Deckers and Cheeseman Lake. Little precipitation fell from the storms to alleviate the unusual dry conditions so early in the season.
In 1978…thunderstorm winds caused damage in southeast Aurora. Winds of 60 to 80 mph blew down numerous fences and damaged several homes under construction. High winds tore docks loose at Cheery Creek Reservoir…sinking 3 or 4 boats and damaging about 15 others. At Stapleton International Airport where winds gusted to 60 mph…a 727 jet suffered 15 hundred dollars damage when wind toppled a runway light onto it. The public reported an unconfirmed tornado 7 miles south-southwest of Stapleton International Airport.
In 1990…a line of thunderstorms moving across metro Denver uprooted a large ash tree…which fell and blocked the outside doors to a Denver elementary school…briefly trapping the students inside. Thunderstorm wind gusts to 69 mph were reported at Jefferson County Airport. Northwest winds gusted to 44 mph at Stapleton International Airport.
In 1991…two tornadoes touched down briefly in Castle Rock… But no injuries or damage were recorded. Heavy thunderstorm rains of 0.50 to 1.10 inches in a couple of hours caused Lena Gulch near Golden to flood. No damage was reported.
In 1996…dry microburst winds of unknown strength overturned a trailer and damaged storage sheds in Strasburg east of Denver.
16-17 In 1981…a heavy rain storm dumped 1 to 2 1/2 inches of rain across metro Denver. Rainfall totaled 1.27 inches at Stapleton International Airport where north winds gusted to 38 mph on 17th.
In 1983…a very strong late spring storm dumped heavy snow over the Front Range. Strong winds with the storm produced blizzard conditions at times. Sustained winds were 20 to 40 mph with a peak gust to 55 mph at Stapleton International Airport. The foothills received 1 to 2 feet of snow with 4 to 12 inches along the foothills. Howling winds whipped the snow into drifts several feet deep…closing schools and highways. Stapleton International Airport was forced to reduce flight operations…closing 2 of 4 runways and stranding hundreds of travelers. Most of the damage and inconvenience caused by the storm was in power outages… Which occurred when wind and heavy wet snow caused hundreds of power poles to snap and topple. About 20 square miles of Denver were blacked out. Precipitation from the storm totaled 1 to 3 inches. At Stapleton International Airport… Snowfall totaled 7.1 inches with a maximum snow depth on the ground of only 2 inches due to melting. The high temperature of 40 degrees on the 17th was a record low maximum for the date. Due to the heavy moisture content of the storm…widespread street flooding occurred on the 18th when much of the snow melted under the warm May sun and temperatures climbed to a high of 57 degrees.
In 1995…significant moisture and upslope flow caused flooding across metro Denver. Moderate to heavy rains… Which began on the evening of the 16th…developed in the foothills and spread eastward over metro Denver throughout the night. The heavy rains brought many creeks and small streams to bankfull or slightly over. Locations along the foothills received between 3 and 4 inches of rainfall from the storm. Boulder received 3.60 inches of rainfall for the 24-hour period…causing minor street flooding near small streams. To the northwest of Boulder…a bridge which crossed Fourmile Creek was washed out. Numerous rock and mudslides occurred in foothills canyons…closing portions of U.S. Highways 6 and 40 and State Highway 119 for a few hours at a time. Rocks were piled 6 feet deep on a stretch of State Highway 119 along with Boulders as large as cars on U.S. Highway 6. A parking lot near a creek in Golden caved in leaving a hole the size of an 18-wheeler. Rushing water washed out a 50-foot stretch of a road in Westminster. Rainfall totaled 1.75 inches at Denver International Airport…but only 1.42 inches at the site of the former Stapleton International Airport.
Severe weather struck the plains of Colorado on Saturday spawning multiple tornadoes. The two most powerful of these, one near Wiggins and another near Wray, have been rated EF-2s on the Enhanced Fujita Scale.
Damage and injuries from both twisters were relatively light, certainly not as bad as they could have been.
The tornado west of Wiggins crossed I-76 and traveled nearly 9 miles reaching 3/4 of a mile wide at one point. It ripped through a private campground at Empire Reservoir damaging and destroying multiple RVs. There were some minor injuries with the storm.
Further east, near Wray, multiple tornadoes were reported, the most significant of which damaged three residences and businesses near the town’s borders. It traveled about 8 miles and at its widest was 440 yards across.
Three other tornadoes were confirmed near Wray although they caused no damage and were rated EF-0s.
Below is some amazing video of the tornado near Wray. Scroll below that for the detailed damage survey from the National Weather Service.
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
314 PM MDT MON MAY 9 2016
...NWS DAMAGE SURVEY FOR 05/07/16 TORNADO EVENT ACROSS MORGAN
AND WELD COUNTIES - UPDATE # 1...
.UPDATE...ADDING ADDITIONAL TORNADOES.
.OVERVIEW...A TORNADO DEVELOPED JUST SOUTH OF INTERSTATE 76 OVER
WELD COUNTY AND THEN MOVE NORTH ACROSS EMPIRE RESERVOIR BEFORE
LIFTING 2 MILES NORTHWEST OF ORCHARD IN MORGAN COUNTY. THERE WERE
TWO MINOR INJURIES WHEN A CAMPER WAS ROLLED OVER. IN ADDITION SEVERAL
CAMPERS WERE DESTROYED AT EMPIRE RESERVOIR.
.TORNADO # 1
RATING: EF-2
ESTIMATED PEAK WIND: 115-120 MPH
PATH LENGTH /STATUTE/: 8.8 MILES
PATH WIDTH /MAXIMUM/: 1320 YARDS
FATALITIES: 0 INJURIES: 2
START DATE: MAY_07_2016
START TIME: 255 PM_MDT
START LOCATION: 5 WEST OF WIGGINS/WELD COUNTY
END DATE: MAY_07_2016
END TIME: 310 PM_MDT
END LOCATION: 2 NORTHWEST OF ORCHARD/MORGAN COUNTY
SURVEY_SUMMARY: MOST OF THE DAMAGE WAS EF0 TO EF1 HOWEVER THERE
WERE A FEW AREAS OF EF2. THE TORNADO WAS LARGE AND 3/4 OF A
MILE WIDE AT ITS PEAK.
.TORNADO # 2...
RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH /STATUTE/: 0.5 MILES
PATH WIDTH /MAXIMUM/: 50 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: MAY_07_2016
START TIME: 315 PM_MDT
START LOCATION: 6 NORTH OF ORCHARD/MORGAN COUNTY
END DATE: MAY_07_2016
END TIME: 316 PM_MDT
END LOCATION: 7 NORTH OF ORCHARD/MORGAN COUNTY
.TORNADO # 3...
RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH /STATUTE/: 0.5 MILES
PATH WIDTH /MAXIMUM/: 50 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: 05_07_2016
START TIME: 325 PM_MDT
START LOCATION: 14 SOUTHWEST NEW RAYMER/WELD COUNTY
END DATE: 05_07_2016
END TIME: 326 PM_MDT
END LOCATION: 13 SOUTHWEST NEW RAYMER/WELD COUNTY
.TORNADO # 4...
RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH /STATUTE/: 0.5 MILES
PATH WIDTH /MAXIMUM/: 50 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: 05_07_2016
START TIME: 335 PM_MDT
START LOCATION: 7 NORTHWEST FORT MORGAN/MORGAN COUNTY
END DATE: 05/07/2016
END TIME: 336 PM_MDT
END LOCATION: 8 NORTHWEST FORT MORGAN/MORGAN COUNTY
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GOODLAND KS
500 PM MDT SUN MAY 8 2016 /600 PM CDT SUN MAY 8 2016/
THIS INFORMATION IS PRELIMINARY AND SUBJECT TO CHANGE PENDING
FURTHER REVIEW OF DOPPLER RADAR, STORM SPOTTER REPORTS AND STORM
VIDEOS, WHICH ARE STILL ARRIVING INTO THE OFFICE.
...NWS DAMAGE SURVEY FOR 05/07/2016 TORNADO EVENT...
.TORNADO #1...
RATING: EF-2
ESTIMATED PEAK WIND: 130 MPH
PATH LENGTH /STATUTE/: 8 MILES
PATH WIDTH /MAXIMUM/: 440 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: MAY 07 2016
START TIME: 551 PM MDT
START LOCATION: 2 N WRAY
END DATE: MAY 07 2016
END TIME: 616 PM MDT
END LOCATION: 10 NNE WRAY
TORNADO PATH WAS ONLY SURVEYED BETWEEN 2 AND 5 MILES NORTH OF
WRAY ALONG AND JUST EAST OF HIGHWAY 385. TORNADO LIKELY CONTINUED
WELL NORTH-NORTHEAST OF WRAY BUT LACK OF ROADS PREVENTED FURTHER
SURVEY. THREE RESIDENCES AND TWO BUSINESSES NORTH OF WRAY WERE
IMPACTED...MAJORITY OF TRACK WAS OVER OPEN COUNTRY.
.TORNADO #2...
RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH /STATUTE/: 0.5 MILES
PATH WIDTH /MAXIMUM/: 25 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: MAY 07 2016
START TIME: 410 PM MDT
START LOCATION: 4 N HEARTSTRONG
END DATE: MAY 07 2016
END TIME: 411 PM MDT
END LOCATION: 5 N HEARTSTRONG
.TORNADO #3...
RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH /STATUTE/: 3 MILES
PATH WIDTH /MAXIMUM/: 50 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: MAY 07 2016
START TIME: 454 PM MDT
START LOCATION: 4 N ECKLEY
END DATE: MAY 07 2016
END TIME: 458 PM MDT
END LOCATION: 7 N ECKLEY
.TORNADO #4...
RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH /STATUTE/: 1 MILE
PATH WIDTH /MAXIMUM/: 50 YARDS
FATALITIES: 0
INJURIES: 0
START DATE: MAY 07 2016
START TIME: 539 PM MDT
START LOCATION: 3 S WRAY
END DATE: MAY 07 2016
END TIME: 541 PM MDT
END LOCATION: 2 S WRAY
THE ENHANCED FUJITA SCALE CLASSIFIES
TORNADOES INTO THE FOLLOWING CATEGORIES.
EF0...WEAK......65 TO 85 MPH
EF1...WEAK......86 TO 110 MPH
EF2...STRONG....111 TO 135 MPH
EF3...STRONG....136 TO 165 MPH
EF4...VIOLENT...166 TO 200 MPH
EF5...VIOLENT...>200 MPH
NOTE:
THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENTS AND PUBLICATION IN
NWS STORM DATA.
May 8 to May 11: This week in Denver weather history
Think we are done with snow for the season? That may be the case this year but it isn’t always so. Looking back at this week in Denver history we do see snowfall has occurred along with more typical spring weather including heavy rains that led to flooding.
From the National Weather Service:
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 land slides…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.
7-8
In 1958…rainfall totaled 2.50 inches at Stapleton Airport.
8
In 1873…a very light rain fell until 5:00 am…when it turned into light snow and sleet and was accompanied by brisk northeast winds. The snow froze as it fell… Breaking the telegraph lines in many places. Precipitation totaled only 0.14 inch in the city.
In 1883…a severe rain and hailstorm struck the city. In 25 minutes the hail was 5 inches deep in the vicinity of the weather office in downtown Denver and reported as deep as 10 to 12 inches in other parts of the city. Gutters were blocked by the hail…and many cellars were flooded. Precipitation from the storm was 1.90 inches with the total for the day recorded at 2.02 inches. The size of the hail was not recorded.
In 1988…a wind gust to 68 mph was recorded at Echo Lake. Northwest winds gusted to 35 mph at Stapleton Airport.
In 1995…high winds of unknown strength blew a camper shell from the back of a pickup truck near Fort Lupton. North winds gusted to 49 mph at Denver International Airport.
In 1996…1 to 2 inch diameter hail was measured in Lochbuie northeast of Denver. Bean size hail fell in Brighton. The large hail fell from severe thunderstorms to the northeast of metro Denver.
In 2003…tornadoes touched down briefly near Brighton… Watkins…and Strasburg…but did no reported damage. Hail to 3/4 inch in diameter was measured near Hudson.
8-9
In 1957…intense heavy rain caused flash flooding on toll gate creek in Aurora where 3 people were killed in a car. Up to 4 inches of rain fell in 5 hours in the Toll Gate Creek basin. The rain also caused flash flooding on sand creek in Aurora and Denver. Rainfall totaled 3.29 inches at Stapleton Airport with most of the rain…2.34 inches… Occurring on the 9th.
8-10
In 1979…4.3 inches of snow fell at Stapleton International Airport where northwest winds gusted to 30 mph on the 8th. Most of the snowfall…2.3 inches…occurred on the 9th. High temperature of only 35 degrees on the 9th equaled the record low maximum for the date.
9
In 1875…a heavy windstorm swept across the city for most of the day. West-northwest winds averaged a sustained speed of 31 mph between 6:00 am and 3:00 pm. The peak wind was sustained to 45 mph at 9:50 am.
In 1918…post-frontal winds were sustained to 40 mph with gusts as high as 43 mph. Only a trace of rain fell.
In 1941…a tornado was noted at 2:20 pm to the northeast of downtown and was followed by another similar shaped cloud or dust roll estimated 3 miles behind. Thick dust followed with heavy gusts of wind. The temperature fell 15 degrees in 10 minutes following the twister. The mild tornado did little damage except to unprotected frame structures. Winds were sustained to 50 mph with the passing of the tornado at Stapleton Airport. It was visible to observers for 10 minutes and was lost from sight as it traveled east into huge rolls of dust. Hail and rain followed with a few hailstones as large as 1/2 inch in diameter downtown. No damage was reported from the hail. Thunderstorm winds sustained to 31 mph produced blowing dust downtown. Precipitation was only 0.07 inch.
In 1983…streams swollen by recent rain and snowmelt caused an earthen dam to collapse…washing out portions of State Highway 67 near Deckers in southern Douglas County.
In 1992…three boys…ages 11…12…and 16…were struck by lightning while taking cover under a large tree during a thunderstorm in Jefferson County…just 7 miles northwest of Denver. The three were seriously injured.
9-10
In 1889…heavy rainfall totaled 2.15 inches in downtown Denver. The cold rain was mixed with snow at times overnight. Temperatures on the 10th ranged from a high of 38 degrees to a low of 32 degrees with north winds sustained to 22 mph.
In 2003…a late spring snowstorm hammered the mountains… Eastern foothills…and urban corridor. The heaviest snowfall occurred north of interstate 70. The heavy wet snow caused damage to trees throughout metro Denver and downed power lines. About 40 thousand people along the urban corridor were without power. Storm total snowfall amounts included: 11.5 inches in Louisville… 8 inches in Boulder and Broomfield; 7 inches in Thornton…Broomfield…at Denver International Airport… And at the site of the former Stapleton International Airport; and 6 inches 4 miles east of Denver. Snowfall ranged from 4 to 9 inches across extreme southern weld County. In the foothills…15 inches of snow fell near Jamestown…9 inches at Rollinsville and Rawah…with 8 inches at Chief Hosa and atop Lookout Mountain. The snow was accompanied by thunder on the afternoon of the 9th at Denver International Airport where west winds gusted to 25 mph on the 9th and north winds gusted to 22 mph on the 10th.
10
In 1875…a windstorm sand-blasted the city from 10:00 am until midnight. Northwest winds sustained to 60 mph brought clouds of sand…which caused high damage to unfinished buildings.
In 1912…a vigorous cold front produced strong north winds and rain. North winds were sustained to 48 mph with gusts as high as 60 mph. Rainfall totaled 1.10 inch.
In 1935…no precipitation occurred…making this one of only two days without precipitation during the entire month. The other day was the 21st. Precipitation totaled 4.95 inches for the month.
In 1956…northwest winds gusted to 53 mph at Stapleton Airport where the visibility was briefly reduced to 1/2 mile in blowing dust.
In 1974…strong winds caused 30 thousand dollars in damage to a building under construction in Lakewood. Microburst winds gusted to 46 mph at Stapleton International Airport.
In 1988…lightning struck a house in Boulder…setting it afire. The house…valued at 170 thousand dollars…was a total loss.
In 1989…golf ball size hail fell over southeast Denver near the junction of I-25 and I-225. Hail to 3/4 inch in diameter fell over southeast Aurora. Only 3/8 inch hail fell at Stapleton International Airport.
In 1991…high winds up to 63 mph raked the eastern foothills. Winds estimated to 50 mph tore a roof from a home in Lafayette. A tower at Jefferson County stadium in west metro Denver was blown over by the high winds. No injuries were reported. Southeast winds gusting to 48 mph at Stapleton International Airport produced some blowing dust. The temperature climbed to a high of 86 degrees… Equaling the record maximum for the date.
In 2005…severe thunderstorms produced hail as large as 2 inches in diameter in and near Longmont.
10-11 in 1918…post-frontal snowfall totaled 4.7 inches in downtown Denver. Northwest winds gusted to 19 mph on the 10th.
In 1923…winds were strong and gusty on both days. Northwest winds were sustained to 40 mph with gusts to 44 mph on the 10th. North winds were sustained to 39 mph with gusts to 46 mph behind an apparent cold front on the 11th.
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.
11
In 1879…an apparent cold front during the afternoon produced sustained north winds as high as 60 mph and great clouds of blowing dust. The dust filled the air until the thunderstorm rain began…which produced 1.46 inches of rainfall. The rain ended during the evening.
In 1900…southwest winds were sustained to 40 mph with gusts to 46 mph.
In 1958…a microburst caused a brief wind gust to 55 mph at Stapleton Airport.
In 1963…south-southwest winds gusted to 48 mph at Stapleton Airport. Winds May have been stronger over west Denver where some buildings were damaged.
In 1998…large hail fell over south metro Denver. Hail as large as 1 1/4 inches in diameter was measured in Parker with 1 inch hail recorded in Littleton and 4 miles south of Lakewood in Jefferson County. Hail to 3/4 inch diameter was measured in Douglas County…11 miles west- northwest of Parker.
11-12
In 2014…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…stormtotals 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.
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.
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…golfball 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.
Colorado’s famously highly variable weather seems to showcase itself during the month of May when a variety of weather conditions can be seen.
Winter-like temperatures and snow are possible as are mid-summer like temperatures or the more typical spring severe weather.
As the month starts out in 2016 we see snow but then warmer, milder weather is expected to arrive for the balance of the first week of the month. Long range forecasts lean toward overall cooler and wetter than normal conditions.
However the month can 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.
May 1 to May 7: This week in Denver weather history
May can bring a variety of conditions from snow and cold to severe thunderstorms and flooding rains. Looking back at this week in Denver weather history we see where all of those events have made an appearance in our past.
From the National Weather Service:
29-2
In 1954…a major storm dumped 10.1 inches of snowfall at Stapleton Airport. Most of the snow…7.5 inches…fell on the 29th and 30th. The maximum snow depth on the ground was 5 inches on the 30th due to melting. No strong winds accompanied the storm.
30-1
In 1980…to the west of Denver…heavy rain changing to snow buried the foothills above 7 thousand feet in 4 to 8 inches of snow. Precipitation in the foothills ranged from 1 to 3 inches…which caused some local flooding. Rain fell at lower elevations. Rainfall at Stapleton International Airport totaled 1.05 inches from the storm.
1
In 1902…northwest winds were sustained to 68 mph with gusts as high as 74 mph in the city during the early morning. The apparent very strong Chinook winds warmed the temperature to a high of 78 degrees.
In 1912…south winds were sustained to 42 mph with gusts as high as 58 mph. South to southwest winds were strong all afternoon.
In 1935…a moderate duststorm blew into the city at around 2:00 pm on northwest winds sustained to 17 mph with gusts to 19 mph. Later in the afternoon…the dust receded to the east in advance of a rainstorm from the west.
In 1988…very strong winds behind a vigorous cold front produced a blinding dust storm that closed I-70 east of Denver. Northeast winds over metro Denver peaked to 45 mph at Stapleton International Airport…but only kicked up some blowing dust. The temperature plunged from a high of 76 degrees at midday to 36 degrees at midnight as light rain changed to light snow.
In 1991…3/4 inch diameter hail fell at Standley Lake in northwest metro Denver.
In 1999…heavy snow developed in the foothills above 7 thousand feet elevation. Snow totals included: 10 inches at Rollinsville…7 inches near conifer…and 6 inches atop Crow Hill. Rain fell across metro Denver.
1-2
In 1903…post-frontal rain changed to light snow overnight… But totaled only 2.0 inches. This was the last snow of the season. Northeast winds were sustained to 45 mph with gusts to 48 mph on the 1st.
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
In 1874…strong winds upset two railroad passenger coaches near Georgetown. The baggage was retrieved and placed in a heavy…large wagon. The passengers then seated themselves on top of the baggage. Another strong gust of wind upset the wagon. The driver’s shoulder was dislocated…and a passenger’s leg was badly injured. In Denver…northwest winds increased and blew in gusts and heavy winds were observed on the ridge tops. On the Kansas Pacific R.R. east of Denver…the wind was so strong that it blew the train back several lengths…which caused the train to be about 7 hours late arriving in the city.
In 1901…south winds were sustained to 50 mph with gusts to 60 mph from an apparent thunderstorm with hail.
In 1944…snowfall of 8.3 inches was accompanied by a thunderstorm. This was the last snowfall of the season and the only snow of the month. Northwest winds were sustained to 25 mph.
In 1955…southwest winds at speeds of 37 mph with gusts as high as 58 mph caused some blowing dust at Stapleton Airport.
In 1983…1 inch diameter hail fell a few miles south of Bennett.
In 1984…3/4 inch diameter hail fell in Northglenn.
In 1988…I-70 east of Denver was closed for the second straight day…this time due to snow and blowing snow producing up to 2 foot drifts. While only 2 to 4 inches of snow fell across metro Denver…Strasburg…just east of Denver…received a foot of snow. North winds peaked to 51 mph at Stapleton International Airport where snowfall totaled only 1.3 inches.
In 1995…lightning struck a house in Westminster sparking an attic fire.
2-3
In 1979…heavy rain changed to snow on the 2nd. Snowfall totaled 3.9 inches at Stapleton International Airport… Where northwest winds gusted to 26 mph. The greatest depth of snow on the ground was only 1 inch at midday on the 2nd due to melting. Total precipitation for the 2 days was 1.65 inches.
2-4
In 1987…a slow moving storm brought rain…wind…and snow to metro Denver. Rainfall totaled 1.04 inches at Stapleton International Airport where north winds gusted to 48 mph on the 3rd. The foothills received 5 to 10 inches of snow.
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
In 1898…heavy snowfall of 6.2 inches fell over downtown Denver. Most of the snow melted as it fell. The greatest snow depth on the ground was 2.5 inches during the evening.
In 1907…the all-time lowest recorded temperature in the month of May…19 degrees…occurred.
In 1925…an apparent microburst produced sustained northeast winds to 44 mph with gusts to 52 mph. Rainfall was only 0.01 inch in downtown Denver.
In 1981…lightning struck 9 golfers at the south suburban golf course. None were injured seriously.
In 1983…hail 1 1/2 inches in diameter fell at Green Mountain west of Lakewood…with 3/4 inch stones reported in Lakewood.
In 1986…a thunderstorm wind gust to 51 mph was recorded at Stapleton International Airport.
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
In 1893…northwest winds were sustained to 42 mph.
In 1971…a funnel cloud was sighted 10 miles southwest of Boulder. Hail stones to 1 inch in diameter fell in southeast Denver…but caused only minor damage.
In 2006…a severe thunderstorm produced hail to 1.00 inch in diameter in Aurora near Cheery Creek Reservoir.
In 2010…high winds downed trees and power lines across parts of the Front Range foothills and urban corridor. Downed power lines sparked a 12-acre wildfire near Conifer. In Boulder…Longmont and Louisville…the wind damaged roofs and broke windows and skylights. Peak wind gusts included: 75 mph in northwest Longmont…71 mph at the national wind technology center and 4 miles south-southwest of Superior…61 mph at Broomfield and 56 mph in Erie. At Denver International Airport…a peak wind gust to 46 mph was observed.
