As we get further into spring the chances for severe weather increase greatly across northeastern Colorado and that is seen in our look back at this week in Denver weather history. We also note the dangers this weather presents as we see events where the weather injured and even killed Coloradoans.

From the National Weather Service:

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 powerlines in the foothills. In Thornton…the roof of a school was damaged by water from the heavy rain. At Stapleton International Airport…1.49 inches of rain were measured over the two day period. The heavy rain ended a severe and prolonged drought.

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

13

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

13-14

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

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

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

14

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

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

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

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

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

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

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

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

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

14-15

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

14-18

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

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 bank full 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.

17

In 1903…southwest winds were sustained to 42 mph with gusts to 45 mph from an apparent microburst which produced only a trace of rain.

In 1960…hail to 3/4 inch diameter was measured in Thornton. Golf ball size hail fell in Arvada.

In 1972…microburst winds gusted to 51 mph at Stapleton International Airport.

In 1975…hail 1/2 to 3/4 inch in diameter fell over western metro Denver.

In 1978…a small tornado touched down in south Aurora damaging 40 homes…6 to a considerable extent. One garage was demolished and blown across the street. Parts of roofs were completely blown away. Several 2×4-inch boards were blown into the sides of houses. Another small tornado in Parker damaged two airplanes. Other funnel clouds were sighted over Northglenn and near Golden.

In 1985…a thunderstorm produced a total of 1.50 inches of rain in Brighton where 0.72 inches fell in 40 minutes. Small hail covered the ground…and there was some street and basement flooding.

In 1987…small hail piled up 4 inches deep in southwest Aurora. There was also widespread street flooding and a few power outages. Hail as large as 3/4 inch in diameter fell at Castle Rock.

In 2000…high winds occurred along and east of the Front Range foothills…as a deep surface low pressure center formed over the northeast plains of Colorado. An amusement park in north Boulder received about 25 thousand dollars in property damage. Peak wind reports included: 88 mph at the National Wind Technology Center…84 mph in Boulder…and 80 mph at the National Center for Atmospheric Research Mesa Laboratory. A powder keg of severe weather…including tornadoes and thunderstorms producing large hail…damaging winds and heavy rain…occurred over the plains to the northeast of Denver. The only severe weather reported across metro Denver was 1 inch diameter hail in Littleton.

18

In 1864…heavy rains combined with melting snow to cause much flooding on north clear creek in Blackhawk. Many bridges on the road to Denver were washed away by the high water on clear creek.

In 1893…northwest winds were sustained to 56 mph with an extreme velocity to 60 mph.

In 1960…large hail to 1 inch in diameter damaged roofs and cars in metro Denver. Heavy snow and rain in the foothills caused rock and landslides…which blocked some highways. There was widespread minor damage from lightning. Hail as large as 1 1/8 inch in diameter was measured at Stapleton Airport where winds gusted to 44 mph.

In 1975…a tornado touched down briefly just south of Buckley Field in Aurora. A few minutes later the same tornado touched down in open country 8 miles northeast of Stapleton International Airport. No damage was reported.

In 1985…3/4 inch hail fell just southeast of Aurora.

In 1988…lightning started a fire at a home in the foothills west of Boulder…causing 50 thousand dollars in damage.

In 1995…strong thunderstorms rumbled across metro Denver dropping mainly pea to marble size hail. However…hail stones as large as 1 1/4 inches in diameter fell in Wheat Ridge and downtown Denver. Hail piled up to 2 inches deep in Wheat Ridge and northwest Denver.

In 1996…the Buffalo Creek Wildfire started and spread rapidly on strong southwest winds at 20 to 30 mph. Dry weather conditions contributed to the spread of the fire… Which burned nearly 12 thousand acres and destroyed 12 structures including some houses.

In 2001…a 19-year-old man was struck and killed by lightning as he was walking along the shoulder of U.S. Highway 36 in Westminster.

In 2003…hail to 3/4 inch in diameter was measured at Denver International Airport.

In 2010…a small tornado touched down near firestone but did no damage.

18-19

In 2011…a severe thunderstorm in central Adams County produced large hail and heavy rainfall on the 18th. Large hail from 1 inch to 1 3/4 inches in diameter…was reported in Commerce City…2 miles south-southeast of Federal Heights…Northglenn…and 2 miles south of Thornton. In Commerce City…the storm uprooted trees and knocked out power lines. A carport was lifted off the ground and struck the power lines overhead. Heavy rain…from 1.0 to 1.5 inches fell in less than 2 hours in Commerce City and near Brighton. The combination of hail and strong winds broke windows in Northglenn. In the foothills…moderate to heavy snow showers developed overnight. Storm totals included: 10.5 inches at gold hill…9.5 inches…3 miles west of Jamestown; 9 inches at Lake Eldora; with 6 inches… 11 miles southwest of Gilpin and 4 miles east-northeast of Nederland. At Denver International Airport…total rainfall over the 2-day period totaled 1.71 inches. In addition…a peak wind gust to 37 mph was recorded on the 18th.

18-20

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

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

19

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

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

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

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

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

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

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

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

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

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

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

19-20

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