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May 22 to May 28: This week in Denver weather history

This Week In Denver Weather History
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.

Continue reading May 22 to May 28: This week in Denver weather history

May 15 to May 21: This Week in Denver Weather History

This Week In Denver Weather History
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.

Continue reading May 15 to May 21: This Week in Denver Weather History

May 7, 2016 Eastern Colorado tornadoes rated at EF-2s

Severe weather more typical of June than late September hit Colorado yesterday.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

This Week In Denver Weather History
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.

Thornton’s May weather preview: Anything from snow to severe storms

Thornton, Colorado May 2013 weather preview.
Thornton, Colorado May 2016 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.

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.

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

May 1 to May 7: This week in Denver weather history

This Week In Denver Weather History
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.

Continue reading May 1 to May 7: This week in Denver weather history

April 2016 weather recap: Temps near normal, precipitation and snow above average

Coming off a very snowy and cold March, Thornton saw a relatively seasonal April 2016.  Temperatures were right near normal but we did see a healthier than average dose of snow and precipitation.

The month started out quite mild.  In fact 13 of the first 14 days saw above average high temperatures.   That changed quickly though at the middle of the month when a storm system brought cold and snow to the Front Range. While most of the white stuff fell to our south, Thornton managed respectable totals over the 16th and 17th of the month.

We then returned to mild weather but only for a few days as a series of low pressure systems passed through the state.  The final three days of the month saw well-below average high temperatures and periods of rain and snow.

Thornton saw an average temperature for the month of 48.0 degrees.  Out at the airport where Denver’s official measurements are kept, the monthly average was a bit cooler at 47.2 degrees.  Both were quite close to the April long term average of 47.4 degrees.

Temperatures in Thornton ranged from a maximum of 78.3 degrees on the 22nd down to a low of 21.9 degrees on the first of the month. DIA saw a maximum of 77 degrees on the 22nd and 23rd and a low of 25 degrees on the first.

In terms of precipitation, Denver’s long term April average is 1.71 inches. On this front, both Thornton and Denver came out above normal.  We saw 2.47 inches of liquid precipitation in our bucket in Thornton while Denver recorded 2.56 inches.

Snowfall was above the 8.9 inch April average in Thornton and Denver.  Thornton however only bested it by a half inch with a total of 9.4 inches for the month. Out at the airport, 15.6 inches was recorded.

Click here to view Thornton’s April 2016 climate report.

Thornton, Colorado's April 2016 temperature summary. (ThorntonWeather.com)
Thornton, Colorado’s April 2016 temperature summary. (ThorntonWeather.com)
Thornton, Colorado's April 2016 precipitation summary. (ThorntonWeather.com)
Thornton, Colorado’s April 2016 precipitation summary. (ThorntonWeather.com)
CLIMATE REPORT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
244 AM MDT SUN MAY 1 2016

...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF APRIL 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              90   04/30/1992
 LOW               -2   04/02/1975
HIGHEST            77   04/23        90     -13       79  04/30
                        04/22
                        04/14
LOWEST             25   04/01        -2      27       27  04/03
AVG. MAXIMUM     59.4              61.5    -2.1     62.1
AVG. MINIMUM     35.1              33.3     1.8     35.3
MEAN             47.2              47.4    -0.2     48.7
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      0               0.3    -0.3        0
DAYS MIN <= 32     11              13.0    -2.0        7
DAYS MIN <= 0 0 0.0 0.0 0 PRECIPITATION (INCHES) RECORD MAXIMUM 8.24 1900 MINIMUM 0.03 1963 TOTALS 2.56 1.71 0.85 2.65 DAILY AVG. 0.09 0.06 0.03 0.09 DAYS >= .01        10               9.1     0.9        9
DAYS >= .10         6               4.5     1.5        6
DAYS >= .50         2               0.9     1.1        2
DAYS >= 1.00        1               0.5     0.5        1
GREATEST
 24 HR. TOTAL    1.22   04/15 TO 04/16           04/16 TO 04/17
                                                          04/17 TO 04/17
                                                          04/17 TO 04/17
 STORM TOTAL       MM                                 MM
 (MM/DD(HH))            MM                    04/17(00) TO 04/17(00)
                                                 04/17(00) TO 04/17(00)7
                                                 04/17(00) TO 04/17(00)7

SNOWFALL (INCHES)
TOTALS           15.6               8.9    6.7

DEGREE_DAYS
HEATING TOTAL     526               529      -3      481
 SINCE 7/1       5230              5731    -501     5205
COOLING TOTAL       0                 1      -1        0
 SINCE 1/1          0                 1      -1        0

FREEZE DATES
RECORD
 EARLIEST     09/08/1962
 LATEST       06/08/2007
EARLIEST      04/01             10/07
LATEST                          05/05
........................................................ 

WIND (MPH)
AVERAGE WIND SPEED              10.9
RESULTANT WIND SPEED/DIRECTION   2/243
HIGHEST WIND SPEED/DIRECTION    43/300    DATE  04/05
HIGHEST GUST SPEED/DIRECTION    53/300    DATE  04/05

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.60
NUMBER OF DAYS FAIR            6
NUMBER OF DAYS PC             15
NUMBER OF DAYS CLOUDY          9

AVERAGE RH (PERCENT)     55

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       2
LIGHT RAIN                6     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                1     SNOW                       5
LIGHT SNOW                8     SLEET                      0
FOG                       9     FOG W/VIS <= 1/4 MILE      4
HAZE                      1

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

April 2016 top shots: Monthly photo slideshow

A picture perfect evening in Adams County. (Carolyn Owens Smith)
A picture perfect evening in Adams County. (Carolyn Owens Smith)

April can be a tricky month weather-wise with everything from mild temperatures to snow to severe weather being possible.  The good thing about that is that it provides plenty of chances for great photos!

April marks a transition between winter and summer for most of the country but for Denver it is especially true as we can see a stunning variety of weather.

The proverbial April showers are certainly a possibility for Denver. Snow? Tornadoes? Thunderstorms? You bet – all can happen!

Throw in our usual wildlife plus the wide variety of birds that return to the Centennial State for the spring and summer and there is a lot going on.

  • Slideshow updated April 23, 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=”72157666986103395″]

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!

Monday brings warmest day of the week for Thornton

We will enjoy one mild day this week and today is it. After this, it goes downhill with unsettled, cooler conditions for the balance.

Today starts out with mostly sunny skies and calm, mild conditions. Temperatures will be climbing to a high of around 73 degrees, a good bit above the average for the date of 64 degrees.

Winds will be a bit breezy this afternoon and the latter part of the afternoon and into the evening brings a chance for showers and thunderstorms. Right now we expect most of these storms to be high-based and bring primarily wind.

Looking ahead, low pressure is going to reign for the balance of the workweek and through the weekend. Temperatures are going to generally be about 10 degrees below normal and each day will feature opportunities for showers, maybe even just a touch of snow even early tomorrow morning and Wednesday morning. Get a complete look at the extended weather forecast here.

April 24 to April 30: This week in Denver weather history

This Week In Denver Weather History
April 24 to April 30: This week in Denver weather history

Weather in Colorado is always interesting but springtime can bring the entire gamut of conditions. Looking back at this week in Denver weather history we see just how varied this time of year – from flooding rains to heavy snowfall to severe thunderstorms it can and has all happened.

From the National Weather Service:

22-24

In 2010…a potent spring storm brought heavy… Wet snow to areas in and near the Front Range Foothills and widespread rainfall across the adjacent plains. In the Front Range Foothills and North-Central Mountains east of the Continental Divide…storm totals ranged from 15 to 30 inches. Storm totals included: 29.5 inches…3 miles southeast of Pinecliffe; 27 inches…8 miles northeast of Four Corners; 23 inches at Willow Creek; 22.5 inches… 13 miles northwest of Golden; 21 inches at Never Summer; 17 inches at Eldorado Springs; 16.5 inches…3 miles west of Jamestown. Denver International Airport reported just a trace of snowfall…but measured 2.01 inches of rainfall for the duration of the storm. In addition…a peak wind gust to 54 mph from the northwest was observed at the airport on the 23rd

23-24

In 1883…snowfall totaled 7.6 inches in downtown Denver.

In 1904…a thunderstorm produced hail during the late evening of the 23rd. Apparent post-frontal rain changed to snow during the early morning of the 24th…but totaled only 2.0 inches. Precipitation consisting of rain…melted hail…and snow totaled 0.60 inch. Northeast winds were sustained to 41 mph with gusts as high as 52 mph on the 24th.

In 1905…rain changed to snow and totaled 8.0 inches. Much of the snow melted as it fell with only 2.5 inches measured on the ground. Precipitation totaled 1.88 inches. Northeast winds were sustained to 20 mph on the 23rd.

In 1942…the South Platte River reached flood conditions in the city. As many as 15 thousand residents were warned to evacuate their homes temporarily. Two lives were lost in the city. Four bridges were washed out by the flood waters and other bridges were endangered. The damage was generally limited to bridges that were in poor condition. However…the flood waters did not overflow their channel banks within the city limits.

In 1980…heavy rain began in the eastern foothills on the night of the 23rd and turned to heavy wet snow on the 24th. Up to a foot and a half of snow fell in the foothills west of Denver. At Stapleton International Airport precipitation totaled 1.58 inches…but only 3.7 inches of snow fell from the storm. East winds gusted to 24 mph.

In 1997…locations in and near the foothills received the greatest snow of the year as a winter-like storm system moved into metro Denver. East to southeast winds at speeds of 15 to 35 mph were common with even stronger gusts above 9 thousand feet. Snow fell at a rate of 2 to 3 inches an hour as deep upslope combined with a moist and unstable air mass. The snow began in the foothills above 7500 feet during the evening of the 23rd. By sunrise the snow level had dropped to 5000 feet. The hardest hit areas extended from I-25 into the foothills. Snowfall totals in the foothills ranged from 1 1/2 to over 3 1/2 feet. In the city…snowfall ranged from 8 to 18 inches. Some snowfall amounts included: 36 inches at Coal Creek Canyon; 31 inches at Nederland and Wondervu; 20 to 24 inches near Blackhawk… At Echo Lake…and North Turkey Creek Canyon; 15 to 19 inches at Boulder…central city…conifer…Evergreen…Georgetown… And Louisville; 8 to 14 inches in Arvada…Broomfield… Westminster…Wheat Ridge…Castle Rock…and Ken Caryl Ranch. Only 2.3 inches of snow fell at the site of the former Stapleton International Airport on the 24th. East winds gusted to 36 mph at Denver International Airport on the 24th.

In 2003…a strong and deep northerly flow circulating around a closed upper low pressure center allowed heavy snow to fall in the mountains and eastern foothills. Snowfall totaled 14 inches in Idaho Springs. Rain was mixed with snow and thunder across metro Denver. Snowfall was only 0.9 inch overnight at the site of the former Stapleton International Airport. Precipitation totaled 1.34 inches at Denver International Airport…where northwest winds gusted to 55 mph on the 23rd.

In 2007…a storm system intensified over southeast Colorado… Allowing for heavy snow and rain to develop over much of north-central and northeast Colorado. Severe thunderstorms preceded the storm system on the 23rd…affecting the urban corridor. Nickel size hail was reported in Boulder and a small landspout touched down near Byers. On the 24th…heavy snow fell in the foothills west of Denver and Boulder…where storm totals ranged from 1 to 2 feet. Heavy snow also occurred along the palmer divide…with storm totals of 10 to 16 inches. Elsewhere…a steady moderate to heavy rainfall was reported. Denver International Airport measured 2.09 inches of rainfall…which shattered the previous 24-hr record of 1.29 inches for the 24th of April. The heavy wet snow caused several power outages. In some instances it took several days to restore power. Several road closures were reported…including interstates 25 and 70. A jackknifed semi-trailer backed up traffic for nearly 20 miles…on southbound I-25…between Denver and Colorado springs. In addition…a 50-ton Boulder blocked the southbound lane of State Highway 285…near Parmalee Gulch. Crews had to use explosives to break up the Boulder and clear the debris. Stranded buses and impassable roadways also forced several school closures.

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In 1935…heavy wet snow fell across metro Denver. The storm started as rain on the 23rd and changed to snow early on the morning of the 24th. There was continuous precipitation for a period of 48 hours. Snowfall totaled 19.0 inches over the city and 20.0 inches at Denver municipal airport. However… Due to warm temperatures in the 30’s…much of the snow melted as it fell and did not seriously disrupt traffic. The greatest snow accumulation on the ground downtown was 12 inches…but it quickly melted. The highest sustained wind speed recorded during the storm was 28 mph from the north on the 23rd. The storm contained 3.16 inches of moisture.

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In 1959…wind gusts to 60 mph recorded in downtown Boulder caused very limited minor damage. West winds gusted to 38 mph at Stapleton Airport.

In 1986…a wind gust to 60 mph was clocked at Golden Gate Canyon.

In 1989…1 3/4 inch diameter hail was reported in Lafayette. Boulder and Louisville reported 3/4 inch hail.
24-25 in 1890…rain changed to snow and totaled 7.0 inches in downtown Denver.

In 1931…heavy snowfall totaled 9.3 inches over downtown Denver. Winds were light during the storm.

In 1996…the second wind storm in less than a week developed east of the continental divide and spread over metro Denver. High winds gusted from 60 to 90 mph. Several power lines and poles were downed. Some of the stronger wind gusts included: 91 mph atop squaw mountain west of Denver…90 mph atop Table Mesa near Boulder…85 mph in Golden Gate Canyon…and 82 mph at Wondervu. Northwest winds gusted to 41 mph at Denver International Airport on the 25th.

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In 1924…post-frontal rain changed to snow…which became heavy and totaled 10.2 inches over downtown Denver. The greatest amount of snow on the ground was 6.0 inches on the 25th due to melting. North winds were sustained to 38 mph with gusts to 42 mph on the 24th.

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In 1902…northeast winds were sustained to 42 mph with gusts to 48 mph.

In 1908…north winds were sustained to 40 mph behind an apparent cold front. Snowfall was 0.5 inch.

In 1928…rain changed to snow…which became heavy and totaled 7.4 inches in downtown Denver. Due to melting…the maximum snow depth on the ground was 4.0 inches at 6:00 pm. This was the last snow of the season. Southeast winds were sustained to 19 mph with gusts to 20 mph.

In 1976…a south wind gust to 54 mph was recorded at Stapleton International Airport. The high winds toppled a 70-foot high cottonwood tree onto the rear of house and a neighboring residence in central Denver.

In 1989…lightning caused heavy damage to a radio transmitter in Parker…knocking a Denver area radio station off the air for 3 hours.

In 1994…weather spotters reported dime-size hail at the intersection of U.S. Highway 287 and c470 in Jefferson County. Marble-size hail covered the ground near Golden to a depth of 1 inch. Pea-size hail was reported covering the ground to a depth of 3 inches in Arvada.

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In 1985…a spring storm brought much rain and snow to metro Denver. The foothills were buried with 15 inches of snow at conifer and 12 inches at Evergreen. At lower elevations… An inch or more of rain fell in Denver and Boulder. The heavy precipitation caused brief power outages in the Denver area. Precipitation totaled 1.06 inches at Stapleton International Airport…including only 0.7 inch of snowfall.

Continue reading April 24 to April 30: This week in Denver weather history