While significant snow events become less frequent this time of year, our look back at this week in Denver weather history shows that they can still occur even toward the end of April. Thrown into the mix is a variety of spring severe weather including tornadoes and deadly lightning.

From the National Weather Service:

19-21

In 1984…a large snowstorm buried most of Colorado under a thick mantle of wet snow. Total snow amounts ranged from 10 to 20 inches across metro Denver and a whopping 20 to 40 inches in the adjacent foothills. The snow closed roads and damaged electrical transformers…causing numerous power outages. Nearly 14 inches (13.6) of snow fell at Stapleton International Airport where the combination of snow and wind closed all but one runway…resulting in the cancellation of many flights. Both I-70 and I-76 were closed to the east of Denver.

19-22

In 1933…a major storm dumped 16.8 inches of snowfall over downtown Denver when rain changed to snow during the early morning of the 20th and continued through midday of the 22nd. Most of the snow fell on the 21st. Due to melting… The most snow on the ground was 10.5 inches at 6:00 pm on the 21st. Before the snow started…a strong cold front on the evening of the 19th produced north winds sustained to 35 mph with gusts to 37 mph. The strong winds deposited a thin layer of dust on the city. North to northwest winds were sustained to 31 mph with gusts to 35 mph on the 20th and to 29 mph with gusts to 32 mph on the 21st.

20-22

In 1957…strong and gusty south to southeast winds raked metro Denver each day. The strongest wind gust of 55 mph occurred on the 21st when blowing dust briefly reduced the visibility to 3/4 mile at Stapleton Airport.

20-23

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.

21

In 1885…rain changed to snow during the early morning and was the heaviest snow of the season. Total snowfall was estimated at 8.0 inches over downtown Denver…but the snow melted rapidly on the ground as it fell. However… The weight of the snow…as well as northwest winds sustained to 29 mph downed telegraph and telephone wires. Several large branches of trees were also broken by the weight of the snow. Precipitation totaled 1.01 inches from the storm.

In 1887…west winds were sustained to 47 mph.

In 1932…the temperature dipped to a low of only 60 degrees… The all-time record high minimum for the month.

In 1988…a small tornado was observed by National Weather Service employees about 3 miles northwest of Thornton. It was on the ground for about 2 minutes. No damage was reported. Later…lightning struck two 14-year-old girls on a softball field in Westminster. One was killed…while the other suffered moderate injuries. Northwest winds gusted to 44 mph at Stapleton International Airport behind a cold front.

In 2010…severe thunderstorms produced large hail…strong winds and a tornado across parts of Adams…Arapahoe… Elbert…and weld counties. The hail…up to 1.50 inches in diameter…came down so heavy along parts of I-70 and I-76 that snowplows had to be called out to remove it. Numerous vehicles were damaged by hail. In weld County…very heavy rain and hail accompanied thunderstorm winds up to 75 mph. Hail up to 1.50 inches was reported near Bennett; 1.25 inches…5.3 miles east of Englewood; 1.0 inch size hail near Buckley Field; with 0.88 inch size hail near Boulder. A weak tornado touched down briefly in Elbert County…about 9 miles southwest of Deer Trail…but did no damage. Several minor accidents were reported with snowpacked and slick road conditions along with very low visibilities. Minor street flooding was reported in southeast Aurora. Denver International Airport recorded 0.30 inches of rainfall. Also…a peak wind gust to 36 mph from the southeast was observed at the airport.

21-22

In 1910…north winds were sustained to 45 mph behind a cold front. Rainfall totaled 0.63 inch.

In 1923…snowfall of 2.0 inches in the city was the only snow of the month and the last measurable snow of the season. Northwest winds were sustained to 25 mph on the 21st.

In 1952…heavy snowfall totaled 7.6 inches at Stapleton Airport. The storm was accompanied by north winds gusting to 33 mph.

In 2001…the second major snow storm in 11 days moved into metro Denver with blizzard conditions developing again across the plains to the northeast of Denver. Snowfall amounts ranged up to 9 inches in metro Denver with up to 23 inches in the foothills. Northwest winds were sustained at 20 to 30 mph with gusts as high as 36 mph at Denver International Airport which was again shut down for nearly an hour by power outages on the 22nd. The outages affected lighting in the concourses…train operations…de-icing and refueling operations…flight information displays…and security screenings. Navigational aids were also affected… Resulting in the cancellation of 58 arriving and departing flights which stranded about 5000 passengers. Across metro Denver storm totals included: 9 inches at Eldorado Springs; 7 inches in Boulder; 6 inches at Ken Caryl…Northglenn and near Sedalia; and 5 inches in Arvada and Morrison. Only 1.7 inches of snow were measured at the site of the former Stapleton International Airport. In the foothills snow totals included: 23 inches near Fritz Peak south of Rollinsville…17 inches near Jamestown…16 inches near Blackhawk…14 inches in Coal Creek Canyon…13 inches at Idaho Springs and near Nederland…11 inches at Aspen Springs…and 10 inches near Bergen Park.

21-23

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.

22

In 1896…southwest winds were sustained to 39 mph with gusts as high 56 mph. The apparent Chinook winds warmed the temperature to a high of 78 degrees.

In 1904…west winds sustained to 40 mph with gusts to 48 mph warmed the temperature to a high of 69 degrees.

In 1925…southeast winds sustained to 42 mph with gusts to 46 mph warmed the temperature to a high of 76 degrees.

In 1958…west-northwest winds gusted to 48 mph at Stapleton Airport.

22-23

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.
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 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.

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

In 1889…north winds were sustained to 48 mph.

In 1913…northeast winds were sustained to 46 mph with gusts to 60 mph behind a dry cold front.

In 1914…a thunderstorm produced considerable hail and 0.29 inch of rain. West winds were sustained to 42 mph with gusts to 48 mph.

In 1942…hail of unknown size fell over the city.

In 1958…a funnel cloud was sighted for 20 minutes…15 miles southeast of Stapleton Airport. The funnel formed in advance of a thunderstorm and hung about a thousand feet below the base of the cloud…but remained aloft. Later in the day…3.6 inches of snow fell at Stapleton Airport.

In 2002…persistent dry conditions in the foothills contributed to the first large forest fire of the season near Bailey. Very dry and windy conditions allowed the fire…initially started by a careless smoker…to grow into a 2400-acre blaze before it could be contained. Fortunately…no significant damage occurred to homes or other property in the area.

In 2006…severe thunderstorms produced large hail across metro Denver. Hail as large as 1.25 inches in diameter fell in south Denver with hail to 0.88 inch across the rest of the city. Hail to 1.00 inch in diameter was reported near Morrison…in south Lakewood…and in Aurora near Cherry Creek. Hail to 0.88 inch was measured in Golden with 0.75 inch hail in east Lakewood.

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 jacknifed 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.

23-25

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.

24

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.

24-26

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.

25

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.

In 2016…a severe thunderstorm produced hail up to one inch in diameter near Castle Rock.

25-26

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.

25-27

In 1877…snow ended around 7:00 am on the morning of the 27th… After falling continuously for 48 hours and totaling an estimated 13 inches in the city. The storm…likely accompanied by strong winds…caused trains to be delayed for 2 to 3 days. One or two roofs of small buildings were crushed by the weight of the snow…and many tree branches were broken in the city. There were a number of reports of livestock losses. One stockman lost 17 horses and several cattle from the snow and cold. Precipitation totaled 1.30 inches from the storm.

26

In 1965…while only 0.40 inch of rain fell at Stapleton International Airport…some communities in the foothills west of Denver reported over 30 inches of snow from the storm.

In 1972…a spring snow storm accompanied by thunder dumped 15.8 inches of heavy wet snow on metro Denver. Strong northwest winds gusting to 35 mph produced blowing snow. The storm was quite intense and greatly hampered travel. High winds caused drifts 10 to 15 feet deep in some areas… Blocking roads and stranding hundreds of motorists. An estimated 500 to 600 people were stranded in the Castle Rock area. Rescue service was provided by heavy army equipment from Fort Carson. Power lines were downed…power poles were toppled…and a number of steel towers carrying high voltage power lines were downed. Some areas northeast of Denver were without power for a week. A large number of cattle and sheep were killed by the storm. The greatest snow depth on the ground at Stapleton International Airport was 12 inches. Warm temperatures following the storm quickly melted the snow.

In 1995…the third major snow storm of the month dumped heavy snow in and near the Front Range foothills. Six to 12 inches of heavy wet snow fell in the western metro suburbs with the heaviest amounts above 6 thousand feet. Both Boulder and Golden measured 10 inches of snow. Only 2.4 inches of snowfall were measured at the site of the former Stapleton International Airport. North winds gusted 28 mph at Denver International Airport.

In 1998…the last in a series of April storms blanketed the foothills with heavy snow. Snowfall amounts included: 17 inches near Blackhawk…15 inches at Idaho Springs…14 inches at Georgetown…11 inches near Conifer and Morrison. Only a trace of snow fell at the site of the former Stapleton International Airport. North winds gusted to 28 mph at Denver International Airport.

26-27

In 1906…rain changed to heavy snow overnight and totaled 7.0 inches over downtown Denver. North winds were sustained to 16 mph on both days. Precipitation totaled 2.16 inches.

In 1932…the temperature remained below freezing for more than 30 consecutive hours. For about 4 of those hours the temperature hovered around 24 to 25 degrees. At this time some early cherry trees were in bloom and apple and lilac blossoms were beginning to open. The leaves of many plants were partly unfurled and vegetation in general was correspondingly advanced due to the warm weather from the 11th to the 22nd. However…there was little apparent injury to foliage and blossoms…but some of the early cherry and apple blossoms were injured. Rain changed to snow on the 26th and continued intermittently through the 27th. Snowfall totaled only 2.0 inches and northeast winds gusted to 22 mph on the 26th.

In 1964…strong winds caused damage to buildings…trees…and power lines. Sustained winds of 37 mph with gusts of 50 to 60 mph were recorded in metro Denver. West-northwest winds gusted to 44 mph at Stapleton International Airport on the 26th.

27

In 1955…west winds at 43 mph with gusts as high as 55 mph were recorded at Stapleton Airport where blowing dust briefly reduced the visibility to 3/8 mile.

In 1966…a northwest wind gust to 51 mph was recorded at Stapleton International Airport.
27-28 in 1919…rainfall totaled 2.03 inches for the two days… Along with a trace of snowfall. Northwest winds were sustained to 24 mph with gusts to 26 mph on the 27th.

In 1975…high winds gusting to 85 mph severely damaged a mobile home in Boulder and caused other minor damage. West winds gusted to 46 mph at Stapleton International Airport on the 28th.

In 1996…heavy snow fell over portions of the Front Range foothills west of Denver. Snowfall amounts ranged from 4 to 7 inches. Only 0.3 inch of snow fell at the site of the former Stapleton International Airport. North winds gusted to 41 mph at Denver International Airport on the 27th.