Certainly April can bring pleasant weather but it also can bring thunderstorms and even heavy, damaging snow as we see in our look back at this week in Denver weather history.

From the National Weather Service:

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In 1989…unusually warm weather resulted in several daily temperature records being broken in Denver. The high temperature of 89 degrees on the 21st exceeded the record maximum for the month at that time. Daily record high temperatures were either exceeded or equaled with 83 degrees on the 20th…88 degrees on the 22nd…and 85 degrees on the 23rd. The low temperature of 55 degrees on the 22nd equaled the record high minimum for the date.

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In 1999…a spring snowstorm dumped heavy snowfall over metro Denver and in the foothills. Nearly 3 feet of snow fell in the foothills with over a foot in the city. The heavy wet snow downed power lines in Douglas and Elbert counties. Scattered outages were reported at Parker…Franktown… Sedalia…and Castle Rock. Some residents were without electricity for as long as 20 hours. The inclement weather was blamed…at least in part…for several traffic accidents along the I-25 corridor between Denver and Castle Rock. Snowfall totals included: 32 inches at Idaho Springs; 31 inches on Crow Hill; 29 inches near Evergreen; 26 inches at Chief Hosa and Coal Creek Canyon; 25 inches at Bailey; 24 inches at Floyd Hill; 23 inches at conifer…Genesee…Golden Gate Canyon…North Turkey Creek…and Pine Junction; 13 inches at Broomfield and near Sedalia; 12 inches in Boulder; 11 inches at Louisville and Parker; and 9 inches at the site of the former Stapleton International Airport.

In 2004…heavy snow fell across metro Denver…when low level upslope conditions developed against the foothills and Palmer Divide. Snowfall totals included: 18 inches in the foothills southwest of Boulder…17 inches at Intercanyon and near Conifer…10 inches near Blackhawk and Parker…9 inches at Castle Rock and near Sedalia…7 inches in Centennial… Littleton…and near Lone Tree. Elsewhere across metro Denver…snowfall generally ranged from 2 to 5 inches. Snowfall was 4.7 inches at Denver Stapleton. Northwest winds gusted to 35 mph at Denver International Airport on the 21st.

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In 1885…the worst snow storm since station records began in 1872 dumped a total of 24.0 inches of snowfall on the city. The 23.0 inches of snow recorded on the 22nd and 23rd was the greatest 24-hour snowfall ever recorded during the month of April. Streets were impassable…roofs caved in… Telegraph and telephone wires were downed…railroads were blocked and trains delayed…and most business came to a complete standstill. Estimated losses were reported to 50 thousand dollars. The total snowfall was partly estimated due to melting. Precipitation from the storm totaled 2.79 inches.

In 1915…post-frontal rain during the day and overnight totaled 2.00 inches. Most of the rain fell on the 22nd.

In 1945…6.7 inches of snow fell over downtown Denver. This was the third major snow in a little over 3 weeks…which made this month the 4th snowiest on record. Northeast winds were sustained to 25 mph and light hail fell on the 22nd.

In 2013…a spring storm brought heavy snow to the mountains… with period of moderate to heavy snow to portions of the Front Range Foothills and Urban Corridor. In the mountains and foothills…storm totals included: 18 inches at Niwot Ridge SNOTEL; 16.5 inches near Ward; 13 inches at Arapahoe Basin and Roach SNOTEL…12 inches near Blackhawk; 11.5 inches near Nederland; 11 inches near Allenspark and at Loveland Ski Area; 10 inches near Idaho Springs and Pinecliffe; with 9.5 inches and near Silverthorne. Along the Urban Corridor storm totals included: 7.5 inches near Morrison; 7 inches at the National Weather Service Office in Boulder and Niwot; 6.5 inches near Arapahoe Park and Superior; with 6 inches at Lafayette and Lakewood. At Denver International Airport…4.7 inches of new snowfall was observed.

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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. Continue reading →

As we enter the latter half of April the weather history calendar starts to reflect shift in the type of weather events we see. There are still plenty of significant snowfall events. However spring severe weather starts to appear with greater frequency including heavy rain, hail and even tornadoes.

From the National Weather Service:

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In 2001…a huge dust storm over southern and Inner Mongolia during April 3rd through the 6th lifted desert dust into the jet stream. This dust cloud moved over metro Denver on the 13th and persisted through the 17th. The cloud created widespread haze…giving the sky a milkish cast due to the scattering of incoming solar radiation.

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In 1900…heavy rainfall totaled 2.33 inches. A trace of snow was mixed with the rain at times.

In 1950…thunderstorms and heavy rain behind a cold front produced 2.13 inches of rain in 24 hours at Stapleton Airport.

In 2003…a fast moving pacific storm system moved across Colorado allowing strong winds to develop over the eastern foothills and metro Denver. Northwest winds gusted to 59 mph at Denver International Airport late in the evening of the 15th.

In 2016…1.22 inches of precipitation was measured at Denver International Airport which was the greatest daily amount for the month.

In 2020…a potent storm system dropped out of the northern Rockies and produced moderate to heavy snow over portions of the Front Range mountains…foothills and adjacent plains. The heaviest snow fell in and near the foothills north of I-70. In the mountains and foothills…storm totals included: 30 inches near Jamestown…27 inches near Nederland…22 inches near Allenspark…21 inches near St Mary`s Glacier…18 inches in Estes Park…16 inches near Crescent Village and Deer Ridge…15.5 inches near Aspen Springs…and 15 inches near Pinecliffe. In Boulder…16.9 inches of snow helped to establish a new seasonal snowfall record of 151.2 inches. The previous seasonal snowfall record in Boulder was 142.9 inches in 1908-1909. Along the I-25 corridor…storm totals included: 14.5 inches in Niwot…13.5 inches in Frederick…13 inches in Broomfield… 12 inches in Lafayette and near Longmont…10.5 inches in Arvada…10 inches in Erie…Louisville…and Westminster…7 inches in Brighton…6.5 inches in Edgewater and Northglenn…and 5.5 inches in Greeley. Snowfall totaled 1.9 inches at Denver International Airport. In 2021…a storm system produced bands of heavy snow in and near the Front Range Foothills. Storm totals included: 13.8 inches at St. Mary`s Glacier…12.9 inches at Aspen Park…10 inches in Genesee…9.5 inches at Ken Caryl…9 inches in Crescent Village…8.5 inches in Arvada and Westminster…8 inches at Evergreen and Sedalia…with 3 to 7 inches elsewhere. At Denver International Airport… 5.7 inches inches of snowfall was observed.

In 2021…a storm system produced bands of heavy snow in and near the Front Range Foothills. Storm totals included: 13.8 inches at St. Mary`s Glacier…12.9 inches at Aspen Park…10 inches in Genesee…9.5 inches at Ken Caryl…9 inches in Crescent Village…8.5 inches in Arvada and Westminster…8 inches at Evergreen and Sedalia…with 3 to 7 inches elsewhere. At Denver International Airport… 5.7 inches inches of snowfall was observed.

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In 1922…heavy snowfall totaled 9.0 inches in downtown Denver. Most of the snow…6.0 inches…fell on the 16th. This was the third major snow storm in a week. Northwest winds were sustained to 43 mph with gusts to 47 mph on the 15th.

In 2016…a powerful spring snowstorm brought heavy…wet snow to areas in and near the Front Range Foothills and Palmer Divide. Storm totals generally ranged from 2 to 4 feet in the foothills with 1 to 2 feet in the mountain west of Denver and along the Palmer Divide. Along the I-25 Corridor storm totals ranged from 6 to 20 inches…with highest amounts across the western and southern suburbs. Some of those totals included: 16 inches in Aurora and Superior…15 inches at the National Weather Service Office in Boulder… 14.5 inches in Broomfield…13.5 inches in Westminster… officially 12.1 inches at Denver International Airport…12 inches in Louisville…11.5 inches in Arvada…11 inches near Englewood…and 10.5 inches near Wheat Ridge. At Denver International Airport…there were 852 flight cancellations… most of which occurred on the 16th. The heavy wet snowfall broke trees limbs and caused scattered power outages. Over five thousand customers were without power on the 16th…and over two thousand on the 17th. Xcel Energy brought in extra crews from surrounding states to help restore power and minimize outage times through the storm. Numerous but mostly temporary road closures from 1 to 5 hours occurred throughout the storm. This included portions of I-70 east and west of Denver…Highway 103 from Idaho Springs to Evergreen and Highway 119 through Black Hawk.

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In 1960…a wind storm struck all of metro Denver. Estimated wind gusts up to 80 mph were registered in Boulder. At Stapleton Airport sustained west-northwest winds over 50 mph with gusts as high as 70 mph produced some blowing dust. The high winds damaged buildings…power and telephone lines…and signs. Five people were injured in metro Denver as a result of the wind storm. Blowing dust reduced visibility at times. The winds were strong and gusty for most of the day.

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In 1944…heavy snowfall totaled 7.5 inches in downtown Denver. Northwest winds were sustained to 18 mph on the 16th.

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In 2009…a potent spring storm brought heavy snow to locations in and near the Front Range foothills. A deep easterly upslope produced nearly 5 feet of snow in parts of the foothills. The heavy snow resulted in the closure of Interstate 70…from Golden west to Vail…for approximately 16 hours. The heavy snow snapped power lines in Evergreen and Nederland. The ensuing outages affected 14200 residents. In the Front Range foothills…storm totals included: 56 inches…3 miles south of Rollinsville; 54 inches…3 miles southeast of Pinecliffe…43 inches at Aspen Springs…42 inches at Evergreen…38 inches near conifer; 37 inches at St. Mary’s glacier…and 34 inches near Nederland. Along the urban corridor and Palmer Divide…the heaviest snow occurred above 5500 feet on the 17th. Storm totals included: 22 inches…8.5 miles southwest of Franktown; 18 inches…10 miles south-southeast of Buckley Air Force Base; 17 inches near Cherry Creek and 7 miles south of Sedalia… 16 inches…6.5 miles southwest of Castle Rock; 15 inches near Beverly Hills; 12 inches near Highlands Ranch and Lafayette…with 11 inches in Broomfield. Elsewhere storm totals ranged from 4 to 10 inches. Officially…only 2.6 inches of snow was observed at Denver International Airport. The 24-hr precipitation for the day however was 1.16 inches… Which established a new record for April 17th.

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In 1889…northwest winds were sustained to 48 mph.

In 1899…apparent post-frontal north winds were sustained to 42 mph with gusts as high as 48 mph.

In 1935…light dust moved over the city behind an apparent dry cold front…which produced northeast winds to 19 mph with gusts to 20 mph.

In 1978…winds estimated to 70 mph occurred in Morrison. Northwest winds gusted to 49 mph at Stapleton International Airport.

In 2000…strong pre-frontal winds and widely scattered thunderstorms caused high winds to develop across northern metro Denver and portions of the northeast plains. Peak wind gusts included 75 mph at Louisville. South winds gusted to only 28 mph at Denver International Airport.

In 2002…strong southwest winds in advance of a cold front gusted to 52 mph at Denver International Airport.

In 2003…severe thunderstorms produced 1 inch diameter hail 7 miles east of Brighton. Strong thunderstorm winds blew out an auto windshield near Denver International Airport where south winds gusted to 48 mph. Continue reading →