Category Archives: Weather History

News and related items pertaining to national, Colorado, Denver and Thornton weather.

December 8 to December 14: This Week in Denver Weather History

This Week in Denver Weather History

A little bit of everything in the history books for this week in Denver weather history. We see a prolonged period of nearly spring-like temperatures and on the opposite end, multiple occasions of bitter cold. There have been, of course, some significant snowfalls as well.

From the National Weather Service:

2-17

In 1939…more than 2 weeks of unseasonably warm weather made the month the 3rd warmest on record. Seven daily temperature records were set…including the all-time record high temperature for the month of 79 degrees on the 5th. Daytime highs were balmy with 14 days in the 60’s and 70’s. Low temperatures dipped to freezing or below on only 5 days. The period was dry with only a trace of snow on the 12th.

3-15

In 1972…a protracted cold spell held an icy grip on metro Denver when maximum temperatures never reached above freezing for 10 consecutive days from the 3rd through the 12th and minimum temperatures dipped below zero on eleven consecutive days from the 5th through the 15th. Daily low temperature records were set with 15 degrees below zero on the 5th…17 degrees below zero on the 6th… And 18 degrees below zero on the 10th. Daily record low maximum readings were set with 3 degrees on the 6th and 6 degrees on the 9th. The very cold temperatures were caused by 3 to 5 inches of snow cover and a Canadian air mass.

5-8

In 1983…high winds occurred in and near the foothills each day. Wind gusts to 63 mph were registered in Golden Gate Canyon on the evening of the 5th. On the evening of the 6th…winds knocked down trees…snapped power lines…and blew out windows across metro Denver. Gusts were clocked to 102 mph in southwest metro Denver…while wind gusts to 38 mph were recorded at Stapleton International Airport. On the 7th…winds overturned a tractor trailer near Castle Rock. After midnight on the 8th…gusts to 97 mph were reported in southeast Boulder. Wind speeds of 60 to 70 mph were reported in other parts of metro Denver.

7-9

In 1919…an apparent arctic cold front brought extreme cold and light snow to the city. Snowfall totaled only 2.5 inches on the 7th and 8th. Temperatures dipped to lows of 14 degrees below zero on the 8th and to 20 degrees below zero on the 9th. Both readings were daily record minimums. High temperatures were only 4 degrees on the 8th and 7 degrees on the 9th.

In 1923…a major storm dumped 13.5 inches of snowfall on downtown Denver. The apparent post-frontal snowfall started during the late afternoon of the 7th and continued through the evening of the 9th. Temperatures dipped from a high of 66 degrees on the 7th with west winds sustained to 35 mph to a low of only 14 degrees on the 9th…with north winds sustained to 25 mph.

8

In 1880…severe winds buffeted the eastern foothills…causing some damage in Boulder.

In 1987…high winds damaged a chimney and roof of a house near Bergen Park in the foothills west of Denver. Gusts were estimated to 70 mph. Northwest winds gusted to 33 mph at Stapleton International Airport.

8-9

In 1943…4.5 inches of snow fell in downtown Denver. This was the only measurable snow of the month. North winds were sustained to 26 mph on the 8th.

In 2003…snowfall totaled 3 to 6 inches across metro Denver. Snowfall was heavier in and near the foothills with 8.0 inches measured in Boulder and 10 miles southwest of Sedalia. Snowfall was 3.9 inches at the site of the former Stapleton International Airport. Most of the snow fell on the 8th…as the snow ended shortly after midnight. North winds gusted to 29 mph at Denver International Airport.

In 2008…an upslope snowstorm produced heavy snow in and near the foothills of Boulder…Jefferson and Douglas counties… And along the palmer divide south of Denver. Storm totals in the foothills ranged from 8 to 15 inches. In Boulder and in areas west and south of Denver…storm totals ranged from 6 to 13 inches. The snowfall measurement at Denver International Airport was 3.9 inches.

8-10

In 1985 a slow moving storm dumped 10 to 20 inches of snow over the northeast plains…closing schools and businesses in many areas along the Front Range north of Denver. At Stapleton International Airport…snowfall totaled 9.9 inches with a maximum snow depth of 7 inches on the ground. North winds gusted to 24 mph. The snow caused long air traffic delays at Stapleton International Airport on the 9th.

In 1997…persistent light to moderate snowfall combined with strong and gusty northerly winds to produce much blowing and drifting snow across metro Denver. The hardest hit areas were south of Denver where north winds at speeds of 20 to 35 mph with gusts to 45 mph caused near whiteout conditions. The strong winds produced drifts 2 to 4 feet deep and dropped wind chill temperatures well below zero. Sections of both I-25 and I-70 and other roads were closed as travel became impossible due to blowing snow. Numerous traffic accidents were reported and a handful of people were stranded during the snowstorm. Snowfall totals included: 22 inches at Conifer…13 inches at Castle Rock…12 inches at Parker…and 8 inches in southeast Aurora. Snowfall totaled 5.5 inches at the site of the former Stapleton International Airport. North winds gusted to 36 mph at Denver International Airport on the 10th.

8-12

In 1932…the second longest sub-zero period on record in Denver occurred. The temperature fell below zero shortly after 1:00 pm on the 8th and remained below zero for 92 hours until 9:00 am on the 12th. The lowest temperature recorded during this period was 13 degrees below zero on both the 9th and 11th. That temperature on the 11th was a record low for the date. High temperatures of 4 on the 8th…5 below zero on the 9th…1 below zero on the 10th… And 6 below zero on the 11th were record low maximum temperatures for those dates. Light north winds at 5 to 10 mph were accompanied by occasional light snow…which totaled only 2.2 inches.

9

In 1898…the very cold air mass that settled over the city behind an apparent cold front on the 7th plunged temperatures to a low of 20 degrees below zero. The high temperature climbed to only 5 degrees.

In 1910…Chinook west winds sustained to 46 mph warmed the temperature to 60 degrees…the warmest reading of the month that year.

In 1919…the minimum temperature dipped to 20 degrees below zero in downtown Denver…setting a record low for the date.

In 1984…high winds occurred in the foothills with a gust to 69 mph recorded at Golden Gate Canyon west of Denver. West winds gusted to 36 mph at Stapleton International Airport.

In 1992…high winds were recorded over most of the day in the Front Range foothills. Wind gusts to 95 mph were measured in the Table Mesa area of Boulder. Northwest winds gusted to 43 mph at Stapleton International Airport.

In 1993…a weather observer in Boulder recorded a wind gust to 73 mph. North winds gusted to 37 mph at Stapleton International Airport.

In 1998…metro Denver and areas in the foothills received the first significant snowfall in more than a month. The upslope snow event deposited up to 17 inches in the foothills with generally 4 to 8 inches across metro Denver west of I-25. Snowfall totals included 17 inches at Crescent Park and 16 inches in nearby Coal Creek Canyon. Other snow amounts included: 16 inches at tiny town; 14 inches at Chief Hosa…Evergreen…and Genesee; 13 inches in Conifer; 12 inches at Nederland; 11 inches in Eldorado Canyon; 9 inches just west of Boulder; 8 inches in Boulder; and 7 inches in Broomfield and Golden. Only 3.6 inches of snow fell at the site of the former Stapleton International Airport. Northeast winds gusted to 26 mph at Denver International Airport.

9-13 Continue reading December 8 to December 14: This Week in Denver Weather History

December 1 to December 7: This Week in Denver Weather History

This Week in Denver Weather History

Extreme weather in December is hardly unusual as long-time residents can attest to. The most common major events involve wind, cold or snow and sometimes all three at once was we can see in our look back at this week in Denver weather history.

From the National Weather Service:

30-1

In 1929…heavy snow blanketed the city. Snowfall totaled 9.8 inches downtown. North winds were sustained to 32 mph with gusts to 37 mph on the 30th.

In 1970…high winds blasted Boulder and the eastern plains. In Boulder…a wind gust to 112 mph was recorded at the National Center for Atmospheric Research with a gust to 96 mph at the National Bureau of Standards.

In downtown Boulder…wind gusts reached 76 mph. At Stapleton International Airport…winds gusted to 47 mph. The high winds caused widespread light to moderate property damage across most of metro Denver. Roofs…signs…trees…power lines…and other property were damaged. Blowing dust reduced visibility to near zero over most of eastern Colorado. Several mobile homes…campers…and semi- trailers were blown off the highways north of Denver.

In 1985…an intrusion of cold arctic air into metro Denver resulted in setting 3 temperature records. The temperature climbed to only 17 degrees on the 30th…setting a record low maximum for the date. On the 1st…the temperature plunged to 6 degrees below zero…setting a record low for the date… And warmed to only 7 degrees…setting a record low maximum for the date.

30-2

In 1975…very strong Chinook winds up to 100 mph caused damage to homes…aircraft…aircraft hangars…mobile homes… Cars…and power lines along the eastern foothills. Strong northwest winds gusted to 39 mph at Stapleton International Airport on both the 30th and the 1st.

1

In 1899…northwest Chinook winds were sustained to 47 mph with gusts to 60 mph. The strong Chinook winds warmed the temperature to a high of 61 degrees…the warmest of the month. The low temperature dipped to only 39 degrees.

In 1972…strong Chinook winds gusted in excess of 65 mph in Boulder. There were no reports of damage. Northwest winds gusted to 38 mph at Stapleton International Airport.

In 1992…strong winds continued through the early morning hours. Wind gusts to over 70 mph were measured at reporting sites in the foothills west of Denver. In west Boulder…wind gusts reached 71 mph with 77 mph measured at Rollinsville. At Stapleton International Airport northwest winds gusted to 39 mph. The walker ranch…an historic site west of Boulder…burned down overnight during the high wind event. Although the winds did not cause the fire…they did hamper efforts to extinguish the blaze.

In 1996…high winds howled in and near the Front Range foothills. Winds gusted to 105 mph at Wondervu southwest of Boulder and to 70 mph at Jefferson County Airport near Broomfield. West winds gusted to only 24 mph at Denver International Airport.

1-2

In 1933…apparent post-frontal heavy snowfall totaled 8.0 inches across downtown Denver. North winds were sustained to 17 mph with an extreme velocity to 18 mph on the 1st.

In 1981 strong winds gusted to over 70 mph along the foothills. A peak gust to 100 mph was recorded at Wondervu. A gust to 94 mph was recorded just west of Boulder. Roofs on houses were damaged in the Evergreen area…and some mobile homes also were damaged. At Stapleton International Airport…northwest winds gusted 44 mph on the 1st and 37 mph on the 2nd.

1-5

In 1913…the 1st marked the start of the heaviest 5-day total snowfall in the city’s history. During this period snowfall totaled 45.7 inches. Starting on the 1st…snow fell intermittently for 3 days and accumulated a little over 8 inches. On the 4th and 5th…an additional 37.4 inches of snow fell. At Georgetown in the foothills west of Denver even more snow fell…86 inches over the 5 days with the most…63 inches…on the 4th. In Colorado…snowfall was heavy along the eastern slopes of the mountains from the Palmer Divide north. High winds during the storm caused heavy drifting…which blocked all transportation. Snow cover of an inch or more from the storm persisted for 60 consecutive days from the 1st through January 29…1914. Additional snowfall in December and January prolonged the number of days. This is the third longest period of snow cover on record in the city.

2

In 1893…northwest winds were sustained to 42 mph with gusts to 46 mph. Snowfall was only 1.4 inches in the city.

In 1895…0.01 inch of melted snow from 0.7 inch of snowfall was the only measurable precipitation of the month in downtown Denver…ranking the month the 3rd driest December on record.

In 1899…post-frontal northeast winds sustained to 44 mph with gusts to 59 mph caused the temperature to plunge from a high of 55 degrees to a low of 15 degrees. Snowfall was only 1.0 inch.

In 1902…apparent post-frontal northwest winds were sustained to 45 mph with gusts to 53 mph. A trace of snow fell.

In 1905…only a trace of snow fell in downtown Denver. This was the only snow and precipitation for the month… Ranking the month the second driest and the second least snowiest December on record.

In 1921…snowfall was 5.5 inches in downtown Denver. Northwest winds were sustained to 24 mph with an extreme velocity of 25 mph.

In 1951…a vigorous pacific cold front produced a northwest wind gust to 51 mph at Stapleton Airport where brief blowing dust was observed.

In 1957…a strong Pacific cold front produced northwest wind gusts to 54 mph at Stapleton Airport where the surface visibility was briefly reduced to 1 1/2 miles in blowing dust.

In 1977…high winds in Boulder lifted a warehouse from its foundation and ripped it apart. Wind gusts from 60 to 103 mph toppled and injured a man while walking. Winds were clocked to 104 mph at Nederland…100 mph at Morrison…and 62 mph at Rocky Flats. Northwest winds gusted to 41 mph at Stapleton International Airport.

In 1996…for the second day in a row high winds ripped the Front Range foothills. Winds gusted to 81 mph in Golden Gate Canyon. West-northwest winds gusted to 37 mph at Denver International Airport.

In 2013…high winds developed ahead of an approaching storm system. The strong winds downed several trees around Evergreen. Peak wind gusts included: 79 mph…4 miles west-southwest of Eldorado Springs; 78 mph…3 miles south of Evergreen; 75 mph and the NCAR Mesa Lab; and 69 mph in Longmont.

2-3

In 1955…snowfall totaled only 2.9 inches at Stapleton Airport. This was the only measurable snowfall of the month.

In 1973…post-frontal heavy snowfall totaled 7.6 inches at Stapleton International Airport where northeast winds gusting to 37 mph caused some blowing snow.

In 1990…strong downslope winds raked the eastern foothills and most of metro Denver. A wind gust to 87 mph was recorded at Rollinsville with wind gusts to 58 mph in Arvada and 55 mph in Lakewood. West winds gusted to 48 mph at Stapleton International Airport on the 2nd.

In 1997…heavy snow fell in the foothills. Conifer received 10 inches of new snow. Snowfall totaled only 2.4 inches at the site of the former Stapleton International Airport on the 1st…2nd…and 3rd. North winds gusted to 24 mph at Denver International Airport on the 2nd.

2-4

In 1909…post-frontal snowfall totaled 6.1 inches in downtown Denver. Most of the snow…5.9 inches…fell between 6:00 pm on the 2nd and 6:00 pm on the 3rd. North winds were sustained to 18 mph on both the 2nd and 3rd.

2-17

In 1939…more than 2 weeks of unseasonably warm weather made the month the 3rd warmest on record. Seven daily temperature records were set…including the all-time record high temperature for the month of 79 degrees on the 5th. Daytime highs were balmy with 14 days in the 60’s and 70’s. Low temperatures dipped to freezing or below on only 5 days. The period was dry with only a trace of snow on the 12th.

3

In 1977…high winds continued in Boulder and were clocked from 74 to 90 mph…causing only minor damage. Northwest winds gusted to 33 mph at Stapleton International Airport where the strong Chinook winds warmed the temperature to a high of 63 degrees.

In 1985…wind gusts to 78 mph were clocked at Table Mesa in Boulder. Winds gusted to 70 mph at Echo Lake west of Denver.

In 2011…another round of snow developed in and near the Front Range foothills. The heaviest snowfall occurred in the foothills of Boulder and northern Jefferson counties. Storm totals included: 13 inches…7 miles southwest of Boulder; 10.5 inches…4 miles east-northeast of Nederland; 10 inches at Genesee; 9.5 inches…4 miles west-northwest of Boulder; 9 inches at Gross Reservoir and 4 miles east of Pinecliffe. Around the urban corridor…storm totals ranged from 3 to 8 inches…heaviest in and around Boulder. At Denver International Airport…3 inches of snow fell.

3-4

In 1968…strong Chinook winds in Boulder gusting to 52 mph downtown caused 7 thousand dollars in damage. Flying debris damaged cars…houses…and other property in Boulder. West winds gusted to 49 mph late on the 3rd and to 45 mph on the 4th at Stapleton International Airport where the temperature climbed to a high of 60 degrees on the 4th.

In 1970…strong winds whistled through Boulder. Sustained winds of 40 mph with gusts to 70 mph were recorded at the National Bureau of Standards in Boulder. Wind gusts to 50 mph occurred in downtown Denver. No damage was reported. On the 3rd…northwest winds gusted to 40 mph at Stapleton International Airport where the Chinook winds warmed the temperature to a high of 66 degrees on the 4th.

In 1999…heavy snow fell over the foothills and metro Denver. The heaviest snowfall occurred in the foothills south of I-70 and near the Palmer Divide. Snowfall totals included: 25 inches near Tiny Town; 18 inches at Conifer; 15 inches near Evergreen; 14 inches at Chief Hosa…8 miles west of Castle Rock…and near Blackhawk; 12 inches at Pine Junction and 8 miles south of Sedalia; 11 inches atop Floyd Hill and in Roxborough; and 10 inches at Castle Rock. Around metro Denver…snowfall totals included: 10 inches at Highlands Ranch…9 inches at Parker…and 8 inches in Aurora and Wheat Ridge. Elsewhere around the metro area…snowfall generally ranged from 3 to 5 inches. Only 3.2 inches of snow fell at the site of the former Stapleton International Airport. North winds gusted to 32 mph at Denver International Airport on the 3rd.

In 2007…high winds developed in and near the Front Range foothills. Peak wind reports included: 88 mph atop Niwot Ridge; 87 mph atop Mines Peak; 80 mph…3 miles southeast of Jamestown; 78 mph at Longmont; 74 mph at Table Mesa. A few power outages occurred in Longmont as broken branches downed power lines. Northwest winds gusted to 38 mph at Denver International Airport on the 4th.

In 2013…a storm system brought heavy snow to parts of the Front Range Foothills. Storm totals included: 12 inches.. 7 miles west-southwest of Evergreen; 10.5 inches…3 miles north of Bailey; 9.5 inches…3 miles west of Jamestown and 5 miles northeast of Ward; 9 inches in Bailey…8.5 inches… 3 miles north of Conifer.

Continue reading December 1 to December 7: This Week in Denver Weather History

November 24 to November 30: This Week in Denver Weather History

This Week in Denver Weather History

Some weeks on the Denver weather history calendar just seem to be busier than others and such is the case with this one. Numerous significant snow and wind events dominate the period around Thanksgiving as well as some examples of extreme cold.

From the National Weather Service:

21-25

In 1952…snowfall of 6.2 inches was measured at Stapleton Airport where northeast winds gusted to 17 mph on the 21st.

23-24

In 1992…a pre-Thanksgiving blizzard belted metro Denver. Gusty north to northeast winds at 30 to 40 mph caused near-whiteout conditions as visibilities were often below 1/4 mile. The strong winds drove snow into drifts of more than 4 feet. Hundreds of holiday travelers were stranded when airlines canceled flights at Stapleton International Airport where snowfall totaled 7.6 inches and north winds gusted to 37 mph. Blizzard conditions began around mid- morning on the 23rd and ended by mid-afternoon…but heavy snow fell through the night. Snowfall totaled: 12 inches at Conifer…Morrison…and Wheat Ridge; 19 inches at Littleton; 16 inches at Castle Rock; 9 inches in Brighton; 8 inches in Aurora; and 6 inches in Parker.

In 1993…a moist upper level disturbance dumped heavy snow over most of Colorado. Snowfall amounts averaged 5 to 8 inches across metro Denver. Snowfall totaled 4.6 inches at Stapleton International Airport where northeast winds gusted to only 20 mph on the 23rd. The very cold air mass caused the temperature to dip to a record low of 8 degrees below zero on the 24th. The temperature that day climbed to only 9 degrees…also setting a record low maximum for the date.

24

In 1915…Chinook winds from the southwest sustained to 40 mph with gusts to 46 mph warmed the temperature to a high of 61 degrees. It was windy most of the day.

In 1949…the low temperature dipped to 56 degrees…the all-time record highest minimum temperature ever recorded during the month of November.

In 1960…violent wind gusts caused some damage in Boulder. West winds gusted to only 22 mph at Stapleton Airport.

In 1980…a snow storm brought 3 to 6 inches of snow across metro Denver. At Stapleton International Airport…only 2.1 inches of snow fell.

In 1989…high winds were recorded in Boulder with a gust to 64 mph. West winds gusted to only 24 mph at Stapleton International Airport.

24-25

In 1908…heavy snowfall totaled 7.0 inches over downtown Denver overnight. North winds were sustained to 15 mph.

In 1930 strong winds raked the Front Range eastern foothills. Winds gusted to 40 mph at Valmont just east of Boulder where minor damage occurred.

In 1970…strong Chinook winds warmed Boulder. At the National Center for Atmospheric Research in Boulder…wind gusts reached 97 mph…while in downtown Boulder winds peaked to 69 mph. Some minor damage occurred. Northwest winds gusted to 39 mph at Stapleton International Airport…and the high temperature warmed to 76 degrees on the 25th…setting a new record maximum for the date.

25

In 1877…northwest winds were sustained to 50 mph.

In 1902…northwest winds were sustained to 45 mph with gusts to 48 mph. The strong apparent bora winds warmed the temperature to a high of only 45 degrees.

In 1943…snowfall of 4.0 inches was the only measurable snow of the month. North winds were sustained to 17 mph.

In 1958…strong pre-frontal Chinook winds struck Boulder and the eastern foothills. A wind gust to 100 mph was recorded northwest of Denver. A gust to 88 mph occurred at Rocky Flats south of Boulder. The windstorm caused considerable structural damage to residential sections of north metro Denver.

In 1959…strong winds raked the eastern foothills including Boulder and Eldorado Springs. Wind gusts to 100 mph were estimated at the Matterhorn restaurant located atop Rocky Flats south of Boulder.

In 1993…a wind gust to 99 mph was recorded atop Squaw Mountain near Idaho Springs.

In 1998…strong winds developed over portions of the Front Range foothills for a brief time following the passage of a weak upper level disturbance. A wind gust to 71 mph was measured atop Blue Mountain near Coal Creek Canyon.

In 1999…strong Chinook winds developed in and near the foothills. Peak wind reports included 100 mph at the Eldora Ski Resort and 77 mph at the National Center for Atmospheric Research mesa lab above Boulder. West winds gusted to 38 mph at Denver International Airport.

In 2010…high winds developed in the foothills of Boulder County. A gust to 75 mph occurred 5 miles northwest of Boulder with a gust to 72 mph at the National Center for Atmospheric Research mesa lab above Boulder. West winds gusted to 24 mph at Denver International Airport.

25-26

In 1887…snowfall totaled 2.9 inches in the city. This was the only measurable snow of the month. Northeast winds were sustained to 18 mph on the 26th when the temperature dipped to 12 degrees below zero.

In 1959…a sharp cold front produced a northwest wind gust to 51 mph…followed by snow and falling temperatures from a high of 60 degrees to a low of 23 degrees at midnight on the 25th. Snowfall totaled 4.4 inches at Stapleton Airport before ending early on the 26th.

In 1972…winds gusted to 104 mph at the Rocky Flats plant south of Boulder. Gusts to 70 mph were recorded at the National Bureau of Standards in Boulder…while in downtown Boulder winds peaked to 68 mph. Some damage was reported. Northwest winds gusted to 47 mph at Stapleton International Airport on the 26th.

In 1984…blowing snow closed I-70 east of Denver…stranding over a thousand travelers in Limon. Denver received only 2.3 inches of snowfall. North winds gusted to 31 mph at Stapleton International Airport.

In 1999…strong Chinook winds redeveloped overnight in and near the foothills. Peak wind gusts included 72 mph atop Blue Mountain near Wondervu and at the National Center for Atmospheric Research mesa lab above Boulder.

25-27

In 1978…heavy snowfall of 6.0 inches was measured at Stapleton International Airport where north winds gusted to 20 mph. Most of the snow…4.8 inches…fell on the 25th. The greatest amount of snow measured on the ground was 5 inches due to settling and melting.

Continue reading November 24 to November 30: This Week in Denver Weather History

November 17 to November 23: This Week in Denver Weather History

 

This Week in Denver Weather History

Powerful, damaging winds, heavy snow and the first official weather observation in the Mile High City highlight this week in Denver weather history.

From the National Weather Service:

14-18

In 1964…the first measurable snowfall of the season totaled 6.0 inches at Stapleton International Airport where northeast winds gusted to 32 mph on the 14th. Most of the snow…4.2 inches…fell on the 14th. This was the only measurable snow of the month.

15-17

In 1991…a strong winter storm dumped heavy snow over metro Denver. Snowfall amounts totaled 15 inches at Castle Rock and Conifer…14 inches at Morrison and Parker…12 inches in southeast Aurora…and 11.6 inches at Stapleton International Airport. Winds were light with the storm.

16-17

In 2010…the combination of heavy snow and strong winds produced dangerous driving conditions in the high country. Blizzard conditions forced the closure of U.S. Highway 6 at Loveland pass and U.S. Highway 40 at Berthoud Pass. Blowing and drifting snow forced the closure of a 65-mile stretch of Interstate 70…west of Idaho Springs. Peak wind gusts included: 68 mph atop Niwot Ridge…55 mph near Blackhawk and Gunsight…and 52 mph at Berthoud Pass. Storm totals in the ski areas west of Denver ranged from 12 to 21 inches. Northwest winds gusted to 55 mph at Denver International Airport on the 16th.

In 2010…the combination of snow and strong winds produced dangerous driving conditions in the mountains west of Denver. Near blizzard conditions forced the closure of U.S. Highway 6 at Loveland pass and U.S. Highway 40 at Berthoud Pass. Blowing and drifting snow closed a 65-mile stretch of interstate 70…between Idaho Springs and Vail Pass. Peak wind gusts included: 68 mph atop Niwot Ridge…62 mph at Loveland Pass…55 mph near Blackhawk and 52 mph at Berthoud Pass.

16-18

In 1921…heavy snowfall totaled 6.5 inches over downtown Denver. This was the only measurable snow of the month. East winds were sustained to 14 mph on the 17th.

17

In 1948…a dry vigorous cold front accompanied by north winds gusting to 60 mph produced extensive blowing dust…which briefly reduced the visibility to 1/2 mile at Stapleton Airport.

In 1993…a wind gust to 70 mph was recorded atop Squaw Mountain near Idaho Springs.

In 1994…winds gusted to 66 mph in Boulder and to 63 mph on Rocky Flats south of Boulder. West winds gusted to 49 mph at Stapleton International Airport.

In 2000…snow fell in the foothills west of Denver…mainly south of the I-70 corridor. Snowfall totals included: 8.5 inches…7 miles south of tiny town; 6 inches at Genesee; and 5 inches…11 miles southwest of Morrison. Only a trace of snow was recorded at the site of the former Stapleton International Airport.

In 2016…bands of moderate to heavy snow fell along the Interstate 70 Corridor as strong fast moving storm system moved across Colorado. Wet roads quickly became icy and snowpacked. A 20-vehicle crash involving semis kept both directions of I-70 closed near Evergreen for a couple of hours. Storm totals included:  11.5 inches…4.5 miles south-southeast of Idaho Springs; 8 inches…5 miles west of Evergreen; 7.5 inches near Conifer…with 4 to 7 inches elsewhere. At Denver International Airport…1.7 inches of snowfall was observed.

17-18

In 1869…the heaviest wind storm in 5 or 6 years raked the eastern foothills including Boulder…Denver…Georgetown… And Golden. Some hundreds of dollars in damage occurred in Boulder.

18

In 1872…fresh west winds contributed to the relative humidity dipping to zero at 2:43 pm. The maximum temperature was 54 degrees.

In 1907…heavy snowfall totaled 6.0 inches over downtown Denver. Snow fell all day. North winds were sustained to 19 mph.

In 1915…northwest winds were sustained to 42 mph with gusts as high as 48 mph. It was windy most of the day.

In 1996…high winds struck the foothills west of Denver. Wind gusts ranged from 70 to 75 mph. A few power lines were downed…but no major outages were reported.

In 1998…strong downslope winds developed during the morning. Wind gusts reached a peak of 72 mph at Jefferson County Airport near Broomfield. West winds gusted to 41 mph at Denver International Airport.

In 1999…high winds developed in and near the Front Range foothills. The strong winds downed power lines…which sparked several small brush fires. In Broomfield… Scaffolding was damaged at the Wadsworth Recreation Center…while flying rocks broke several windows at a local bank building. Peak wind gusts included: 91 mph atop Blue Mountain near Wondervu…88 mph atop the Gamow Tower on the University of Colorado campus in Boulder… 83 mph at Jefferson County Airport…81 mph at the National Center for Atmospheric Research mesa lab above Boulder…and 80 mph at Wondervu. West-northwest winds gusted to 48 mph at Denver International Airport.

18-19

In 1975…snowfall totaled only 5.5 inches and north winds gusted to 35 mph causing some blowing snow at Stapleton International Airport…while a major blizzard struck southeastern Colorado.

In 1985…4 to 7 inches of snow fell across metro Denver. Snowfall totaled 4.4 inches at Stapleton International Airport where north winds gusted to 23 mph.

In 1991…another strong winter storm produced heavy snow over metro Denver. Snowfall totaled 9.5 inches at Stapleton International Airport with 9 inches at Parker… And 8 inches in southeast Denver…Morrison…and Wheat Ridge. This second storm brought the 5 day (15th-19th) snowfall total at Stapleton International Airport to 21.1 inches. The greatest depth of snow on the ground was 13 inches on the morning of the 19th. The adverse effects of the two storms were diminished by the lack of significant winds.

Continue reading November 17 to November 23: This Week in Denver Weather History

November 10 to November 16: This Week in Denver Weather History

This Week in Denver Weather History

Wintry weather is not unusual this time of year but as our look back at this week in Denver weather history shows, high winds can be just as common and oftentimes more damaging.

From the National Weather Service:

8-10

In 1985…Indian summer came to an abrupt end when a winter storm dumped 10 to 18 inches of snow in the Front Range foothills and 6 to 10 inches across metro Denver…snarling traffic and causing flight delays of up to 3 hours at Stapleton International Airport. The temperature plunged from a high of 66 degrees on the 8th to a low of only 13 degrees on the 9th…after the passage of a vigorous cold front with northeast winds gusting to 32 mph. The temperature climbed to only 19 degrees on the 10th…setting a record low maximum for the date. Snowfall totaled 7.3 inches at Stapleton International Airport with most of the snow…7.1 inches…falling on the 9th.

10

In 1897…west Chinook winds sustained to 51 mph with gusts to 60 mph warmed the temperature to a high of 64 degrees.

In 1915…southwest winds were sustained to 41 mph with gusts as high as 44 mph.

In 1955…strong winds raked the eastern foothills. A wind gust to 80 mph was recorded atop Rocky Flats south of Boulder where some damage occurred.

In 1995…snowfall totaled 6 to 9 inches in the foothills west of Denver…while only 2.2 inches of snow fell at the site of the former Stapleton International Airport. North-northeast winds gusted to 31 mph at Denver International Airport.

In 1998…strong bora winds gusting from 70 to 92 mph coupled with blowing snow created whiteout and slick black ice conditions at the base of the foothills west of Denver. State Highway 93 between Golden and Boulder and C-470… Near the Morrison interchange were closed for several hours due to multiple car accidents. Dozens of motorists were stranded until weather conditions improved. A small motor home was a total loss when it caught fire after being blown on its side by strong crosswinds. A man was injured when he was blown off a vehicle while attempting to rescue the occupants. Wind gusts included: 92 mph atop Blue Mountain near Coal Creek Canyon…83 mph atop Fritz Peak near Rollinsville…and 77 mph at Jefferson County Airport near Broomfield. West winds gusted to 36 mph at Denver International Airport.

In 2000…freezing drizzle was widespread across northeastern Colorado with the heaviest amounts near the foothills in the evening. The freezing drizzle made many highways icy and slick…which contributed to a number of traffic accidents. Some highways across metro Denver were closed at times…including portions of State Highway 119 between Boulder and Longmont and U.S. 36 between Westminster and Boulder. State Highway 93 between Boulder and Golden atop Rocky Flats became nearly impassable due to a coating of ice by late evening.

10-11

In 1911…a strong cold front produced snow and a cold wave. The temperature dropped 68 degrees from a high of 66 degrees at 12:40 pm on the 10th to a low of 2 degrees below zero at 7:15 am on the 11th. The low temperature of 23 degrees at midnight on the 10th was also the high temperature on the 11th. Northeast winds were sustained to 42 mph with gusts to 51 mph. Snowfall was only 2.5 inches.

In 1982…up to 4 inches of snow fell over the higher terrain between Denver and Colorado springs. Winds gusted to 50 mph along the foothills. Rainfall totaled 0.27 inch with only 0.1 inch of snow on the 11th at Stapleton International Airport where north winds gusted to 39 mph. Dense fog with visibilities as low as zero persisted all day on the 10th.

10-14

In 2014…an Arctic cold front on the 10th…associated with a strong storm system over the northern Rockies blasted into northeast Colorado. The temperature in Denver plummeted from the high of 64 degrees at 4:37 pm to 34 degrees by 5:53 pm. The temperatures continued to fall and dropped into the teens by early evening. The Arctic airmass remained entrenched over the region through the morning of the 14th…with the high temperatures failing to reach the teens from the 11th through the 13th. This was the first time since records have been taken in Denver…dating back to 1872…that there were three consecutive days with the maximum temperatures remained below 20 degrees in the month of November. In addition to the frigid temperatures…0.1 inch of snowfall was observed on 11th at Denver International Airport…which marked the first measureable snowfall for the season. An additional 2.2 inches of snowfall was measured on the 12th. Several temperature records were broken. A record low max of 16 degrees on the 11th broke the previous record of 19 set back in 1916. A record low max of 6 degrees on the 12th broke the previous record of 9 degrees…also set in 1916. The record low of -13 on the 12th…shattered the previous record of -4 degrees set back in 1872. Even more impressive…the record low of -14 degrees on the 13th broke the previous record of -3 degrees set back in 1916. The sudden drop in temperatures on the 10th…followed by several days of sub-freezing temperatures chilled trees to the core. The record drop in temperatures…preceded by mild fall temperatures…damaged or killed scores of trees across the Urban Corridor and Northeast Plains. At the time…the trees were not finished with the hardening process that enables them to withstand winter weather. Many were instantly flash-frozen…and some would not show signs of damage until spring of 2015. Of the 2.2 million trees in the city of Denver alone…tens of thousands were killed from the November frost. Denver estimated a citywide loss of more than 10 million dollars.

11

In 1901…a trace of rain fell in the morning…and a trace of snow fell in the afternoon. This was the only snowfall and precipitation for the month…ranking it the driest November on record…along with November of 1899 and 1949. The month also ranks as the second least snowiest November…along with Novembers in other years.

In 1903…northwest winds sustained to 45 mph with gusts to 56 mph warmed the temperature to a high of 56 degrees.

In 1912…rain changed to snow…which became heavy…and totaled 6.5 inches over downtown Denver. Precipitation was 1.02 inches…the greatest calendar day precipitation ever recorded in November. Northeast winds were sustained to 27 mph with gusts to 29 mph.

In 1919…light snow fell from an apparent clear sky during the early afternoon. The first snow was observed at about 12:40 pm and continued at least 30 minutes before clouds could be seen forming…followed by the sky becoming totally cloudy. During this time the temperature fell from 50 degrees at noon to only 18 degrees at 100 pm and plunged to 6 degrees at 5:45 pm. A low temperature of 2 degrees was recorded overnight. Northeast winds were sustained to 33 mph with gusts to 36 mph between noon and 1:00 pm behind an apparent arctic cold front. Snowfall was only 0.1 inch.

In 1949…north winds gusted to 50 mph at Stapleton Airport. A trace of rain fell. Another trace of rain on the 15th was the only precipitation of the month…making the month one of the driest Novembers on record and the least snowiest with no snow. This was the first November since 1882 without snow.

In 1959…strong northwest winds struck Boulder and the foothills causing some damage. West winds gusted to 37 mph at Stapleton Airport.

In 1995…strong downslope winds gusting to 84 mph blew out a few car windows in Boulder County. Winds gusted to 69 mph at Golden…Lakewood…and Table Mesa in Boulder. West-northwest winds gusted to 43 mph at Denver International Airport.

In 2000…heavy snow occurred in the foothills southwest of Denver and over monument ridge south of Denver. Snowfall totals included: 6.5 inches near Parker… 6 inches near Bergen Park…5 inches at Genesee and near Sedalia…and 4 inches at Coal Creek Canyon and St. Mary’s glacier. Snowfall totaled 1.6 inches at the site of the former Stapleton International Airport.

In 2003…strong downslope winds developed along the Front Range. Peak wind reports included 91 mph atop Blue Mountain near Wondervu and 75 mph in Boulder. Damaging winds downed power lines in Boulder County. North of Golden…a semi-truck was blown over by the winds near the intersection of State Highways 72 and 93 atop Rocky Flats. At the same location…blowing rocks shattered several car windows at an RTD Park and Ride. West winds gusted to 40 mph at Denver International Airport.

Continue reading November 10 to November 16: This Week in Denver Weather History

November 3 to November 9: This Week in Denver Weather History

This Week in Denver Weather History

Heavy snow and damaging winds, extreme conditions typical this time of year, make repeated appearances in our look back at this week in Denver weather history.

From the National Weather Service:

2-3

In 1974…heavy snowfall totaled 6.1 inches at Stapleton International Airport where north winds gusted to 23 mph on the 3rd. Most of the snow fell on the 3rd. Maximum snow depth on the ground was 5 inches.

In 1990…a winter storm dumped 3 to 8 inches of heavy wet snow across metro Denver. In the foothills snow amounts ranged from 4 to 10 inches. Slushy snow and ice-covered roads snarled traffic. The snow…ice…and poor visibilities were blamed for numerous traffic accidents. Low clouds… Fog…and snow delayed air traffic at Stapleton International Airport for at least 90 minutes on the afternoon of the 2nd. Snowfall totaled 5.4 inches at Stapleton International Airport where north winds gusted to 21 mph.

In 2018…a powerful and moist Pacific jet stream brought a period of moderate to heavy snow and blowing snow to the mountains west of Denver with up to a foot of snow. A strong gust front generated from dissipating showers near the foothills of southeast Larimer and eastern Boulder counties pushed across the I-25 corridor and adjacent plains. As the gust front swept across Denver International Airport…a peak wind gust to 58 mph was observed from the west-northwest.

2-5

In 1946…a major snow storm dumped 30.4 inches of heavy snowfall downtown and 31.0 inches at Stapleton Airport. The winter storm closed schools and disrupted all forms of transportation in the city. The greatest depth of snow on the ground was 28 inches at the airport. The duration of the snowfall…from 4:22 am on the 2nd to 3:08 am on the 5th… A total of 70 hours and 46 minutes…is the second longest period of continuous precipitation on record and the second heaviest snowfall of record at the time in Denver. The 17.7 inches of snowfall on the 2nd and 3rd was the greatest 24- hour snowfall ever recorded during the month of November. Buses and street cars had a difficult time…and many cars were abandoned along roadsides and streets for several days. Secondary roads in rural areas were blocked for 2 to 3 weeks. Several buildings in the city collapsed or were damaged from the weight of the heavy snow. Football games were canceled. Livestock losses were high over eastern Colorado. The precipitation from this storm alone exceeded the greatest amount ever recorded in Denver during the entire month of November previously. The precipitation recorded downtown was 2.03 inches…and the previous record for the entire month of November was 1.95 inches in 1922. North winds were sustained to 26 mph on the 2nd.

3

In 1940…the longest period without snow…200 days…ended on this date with the first snow of the season…a trace…on November 4…1940. The last snow of the previous season… Also a trace…occurred on April 17…1940.

In 1959…a rare thunderstorm in November occurred around sunrise. Rainfall measured only 0.02 inch at Stapleton Airport.

In 1993…periodic high winds buffeted the foothills west of Denver. Wind gusts to 90 mph were recorded at Rollinsville in the foothills southwest of Boulder…while gusts to 85 mph were observed atop Squaw Mountain near Idaho Springs. West winds gusted to 37 mph at Stapleton International Airport.

In 1996…a rare November thunderstorm during the early evening produced 0.10 inch of rain at Denver International Airport and only 0.06 inch of rain at the site of the former Stapleton International Airport.

In 2005…strong winds developed over the urban corridor. While the damaging winds were in the Fort Collins area… High winds also developed to the south of Denver in Douglas County. Peak wind reports included 70 mph at Franktown…65 mph in Castle Rock…and 61 mph in Sedalia. West winds gusting as high as 47 mph warmed the temperature to a high of 69 degrees at Denver International Airport. Winds were strong and gusty for most of the daytime hours across metro Denver.

3-4

In 1994…a fast moving snow storm dumped 8 to 9 inches of snow on Boulder…Broomfield…and Lafayette. Snowfall totaled only 1.8 inches at Stapleton International Airport where on the 3rd east winds gusted to 20 mph and some freezing drizzle fell.

4

In 1940…a trace of snow fell in downtown Denver. This marked the start of the shortest snow season on record… 167 days…through April 19…1941…when 0.4 inch of snow fell.

In 1959…high winds caused damage in many areas of the eastern plains. In Denver…winds averaged 40 mph with gusts to 70 mph. Some damage was reported to utility lines…signs…and vehicles. Northeast winds were sustained to 30 mph at Stapleton Airport.

In 2017…strong winds developed over the Palmer Divide. Peak wind gusts included 66 and 61 mph near Monument.

4-5

In 1933…the first measurable snow of the season totaled only 2.5 inches. This was the only measurable snow of the month. Northwest winds were sustained to 27 mph on the 4th.

In 1951…heavy snowfall of 5.7 inches was measured at Stapleton Airport where northwest winds gusted to 32 mph.

Continue reading November 3 to November 9: This Week in Denver Weather History

October 27 to November 2: This Week in Denver Weather History

This Week in Denver Weather History

Our look back this week in Denver weather history highlights why being prepared for winter weather is so crucial. From massive winter storms to damaging wind and deadly exposure to the elements, we have seen each in the past.

From the National Weather Service:

25-27

In 1897…a major storm dumped 13.5 inches of snowfall over downtown Denver. Rain changed to snow during the evening of the 25th and continued through mid-morning of the 27th. Most of the snow…12.0 inches…fell on the 26th when north winds were sustained to 36 mph and gusts were as high as 46 mph. Temperatures during the storm were in the 20’s and lower 30’s. Precipitation (rain and melted snow) totaled 1.21 inches.

In 2021…the minimum temperature at Denver International Airport dropped into the single digits for three consecutive mornings: 8 degrees…4 degrees and 8 degrees respectively.

26-27

In 1971…strong winds raked Boulder. At the National Bureau of Standards wind gusts to 62 mph were recorded…while in downtown Boulder winds peaked to 48 mph. At Stapleton International Airport…northwest winds gusted to 38 mph on the 26th and north winds gusted to 36 mph on the 27th.

In 1976…the first measurable snow of the season turned into a major storm. Traffic was halted for several hours on highways to the west of Denver where 8 to 12 inches of snow fell in the foothills. Snowfall totaled 7.2 inches at Stapleton International Airport where north winds gusted to 30 mph. Most of the snow…6.3 inches…fell all day on the 26th. The greatest snow depth on the ground was 5 inches on the morning of the 27th.

27

In 1980…the first snowfall of the season totaled only 1.5 inches with 0.10 inch of moisture at Stapleton International Airport where the maximum snow depth on the ground was only 1 inch due to melting. This was the only measurable precipitation of the month…making it the driest October since 1962 when only 0.03 inch of precipitation was measured.

In 1994…wind gusts to 70 mph were recorded atop Squaw Mountain…5 miles south of Idaho Springs…and at Rollinsville in the foothills southwest of Boulder. Northwest winds gusted to 28 mph at Stapleton International Airport.

27-28

In 1874…strong west winds in Boulder along with a reported tornado produced 150 dollars in damage.

In 1913…a strong cold front produced sustained northeast winds to 35 mph with gusts as high as 38 mph on the 27th. Overnight snowfall totaled 5.8 inches. Temperatures plunged to a low of 17 degrees on the morning of the 28th after a high of 60 degrees on the 27th.

27-30

In 2009…a powerful early season storm brought heavy snow to the Front Range. The combination of a deep northeasterly upslope flow coupled with abundant moisture and lift with the developing storm system produced an extended period of moderate to heavy snowfall. The heavy wet snow accumulated on trees and resulted in broken branches and scattered electrical outages. Interstates 70 and 76 were closed east of Denver. Numerous other roads and highways were shut down. The Red Cross set up numerous emergency shelters for stranded travelers. The blowing snow at Denver International Airport forced the cancellation of hundreds of flights. Schools were also closed. In the foothills storm totals included: 46 inches… 3 miles southeast of Pinecliffe; 42 inches…3 miles southwest of Conifer; 34 inches…3 miles north of Blackhawk; 30 inches at Aspen Springs and near Evergreen… 23 inches at Roxborough Park…and 20 inches…3 miles south-southeast of Morrison. Across the urban corridor storm totals included: 25 inches in Highlands Ranch; 21.5 inches near Louisville…20.5 inches in Broomfield… 20 inches at Lafayette…17.5 inches in Boulder…17 inches in Westminster…16.5 inches in Erie; 15.5 inches in Arvada and 5 miles west-northwest of Littleton…15 inches in Littleton…14 inches in Englewood…13.5 inches in Lakewood and 6 miles north of Thornton; 13.3 inches at Denver International Airport…11 inches…4 miles south of Denver; 10.5 inches…2 miles north of cherry hills village and Niwot.

28

In 1917…post-frontal snowfall totaled 6.5 inches in the city. North winds sustained to 30 mph with gusts to 33 mph caused the temperature to plunge from a high of 58 degrees to a low of 9 degrees by midnight.

In 1967…winds gusted to 65 mph in downtown Boulder…causing minor damage. South winds gusted to 32 mph at Stapleton International Airport.

In 1991…the first major snow of the season hit metro Denver as a cold arctic air mass moved over the area. Snowfall amounts across northeast Colorado ranged from 3 to 10 inches with 4.4 inches of snowfall recorded at Stapleton International Airport where north winds gusted to 22 mph. The low temperature dipped to 13 degrees.

In 1993…high winds buffeted the Front Range foothills. A wind gust to 83 mph was recorded atop Squaw Mountain…35 miles west of Denver…and a gust to 76 mph occurred near Rollinsville southwest of Boulder.

28-29

In 1993…an upper level disturbance combined with a moist upslope flow to bring heavy snow to portions of metro Denver. Snowfall amounts ranged from 5.4 inches at Stapleton International Airport to 14 inches in Boulder. New snowfall totaled 8 inches at Gross Reservoir in the foothills 5 miles southwest of Boulder. On the 28th…north winds gusted to 30 mph at Stapleton International Airport where the temperature climbed to only 25 degrees on the 29th…equaling the record low maximum for the date.

28-30

In 1971…a vigorous cold front plunged temperatures from a high of 70 degrees on the 27th to record low levels on the 29th and 30th. Snowfall totaled 3.1 inches at Stapleton International Airport where north winds gusted to 23 mph. Some freezing drizzle also fell on the 28th. Record daily low maximum temperatures of 32 degrees on the 28th and 25 degrees on the 29th were established along with a daily record minimum of 13 degrees on the 30th.

Continue reading October 27 to November 2: This Week in Denver Weather History

October 20 to October 26: This Week in Denver Weather History

This Week in Denver Weather History

Temperatures continue to cool as we get further into fall and our look back at this week in Denver weather history provides some insight into the types of extreme weather that are possible this time of year. Noteworthy events include many incidences of damaging wind and some monstrous snowstorms.

From the National Weather Service:

18-23

In 2003…an extended warm spell resulted in 5 new temperature records. The high temperature of 84 degrees on the 18th equaled the record high for the date. High temperatures of 86 degrees on the 19th…83 degrees on the 21st…and 84 degrees on the 22nd were record highs for the dates. Low temperature of 49 degrees on the 23rd was a record high minimum for the date. Low temperatures during the period were in the 40’s and lower 50’s.

19-20

In 1990…an early winter storm dumped heavy snow across metro Denver. Snowfall amounts ranged from 4 to 8 inches in the foothills above 6500 feet elevation…4 to 7 inches in the Castle Rock area…and 2 to 5 inches across most of metro Denver and Boulder. Snowfall totaled 3.6 inches at Stapleton International Airport where northwest winds gusting to 48 mph kicked up some blowing dust shortly after a cold frontal passage on the 19th. However… Temperatures were warm enough to keep most roadways wet and slushy at lower elevations.

19-23

In 1906…heavy snowfall totaled 22.7 inches in the city over the 5 days. Rain changed to snow on the evening of the 19th…and snow continued through the late afternoon of the 23rd. The heaviest amount of snowfall…16.0 inches…fell from 8:00 pm on the 20th to 8:00 pm on the 22nd. The most snow on the ground was 13.3 inches on the evening of the 23rd. This was the first snow of the season and the only snow of the month. Winds during the storm were from the north at sustained speeds of 20 to 30 mph each day. Temperatures during the storm were generally in the 20’s.

20

In 1878…between 3:00 pm and 4:00 pm wind speeds averaged 48 mph with a maximum 1 minute sustained velocity to 96 mph at both 3:27 pm and 3:48 pm in downtown Denver. This is the highest sustained wind speed ever recorded in the city.

In 1986…a rare late October thunderstorm produced 3/4 inch diameter hail at Centennial Airport. Hail piled up 2 1/2 inches deep…causing some street flooding in south metro Denver.

In 2019…strong bora winds swept across the foothills and adjacent plains. Peak gusts included: 82 mph…3 miles southwest of Rocky Flats; 78 mph near White Ranch Open Space; 75 mph near Genesee and Georgetown; with 63 mph at Firestone. At Denver International Airport…a peak gust of 49 mph was observed from the west.

20-21

In 2007…a storm system brought heavy snow to the southern Denver suburbs as well as the Palmer Divide south of Denver. Storm totals included: 7.5 inches near Castle Rock…Lone Tree and Greenwood Village…with 6.5 inches at Elizabeth. Snow drifts up to 2 feet deep were observed 6 miles south-southwest of Elizabeth. In the Denver Stapleton area…2.0 inches of snow was observed.

In 2009…heavy snow developed along the Palmer Divide south and southeast of Denver as a storm system tracked across southern Colorado and northern New Mexico. Storm totals included: 15 inches…15 miles north of Elizabeth…9 inches…5 miles south-southwest of Arapahoe Park; 8 inches in Highlands Ranch…5 miles south- southeast of Sedalia; 6.5 inches…8 miles southwest of Bennett and 6 inches in Parker. At Denver international… Only 1.5 inches of snowfall was observed.

20-22

In 1936…5.5 inches of snow fell over downtown Denver. Most of the snow…4.5 inches…fell on the 20th.

21

In 1920…the rare event of snow from a thunderstorm occurred in the city during the evening. Brilliant flashes of lightning and loud peals of thunder were first noted at 7:35 pm. Light rain began falling at 8:30 pm…and light moist snow began falling a few minutes later. Some soft hail was also seen falling with the rain and snow…but both melted almost as fast as they fell. The hail only continued for a few minutes…and the rain and snow ceased about 9:40 pm. The snowfall was the first to occur in Denver this season. The amount of precipitation at the station measured only 0.01 inch…but heavier amounts were reported from other parts of the city. Snowfall was only a trace.

21-22

In 1978…heavy rain on the 21st changed to snow by daybreak on the 22nd and continued the rest of the day. This was the first measurable snowfall of the season…but totaled only 1.7 inches at Stapleton International Airport where east winds gusted to 29 mph. While only a trace of snow covered the ground…precipitation totaled 1.27 inches.

22

In 1878…winds were sustained to 42 mph.

In 1887…the first measurable snow of the season occurred… Ending the longest snow-free period in Denver…232 days… Since the last snow on March 5th.

In 1947…the first snow of the season totaled only 1.6 inches. Post-frontal north winds caused temperatures to plunge from a high of 60 degrees at midnight to a low of only 30 degrees 24 hours later. This was the only snow of the month.

In 1985…high winds gusting from 60 to 80 mph buffeted the Front Range foothills. The strongest reported wind gust was 89 mph in eastern Boulder. A treehouse east of Boulder was set on fire by a downed power line. Two people in Boulder were injured. A woman broke her arm when the strong winds knocked her to the ground. A carpenter in the city suffered a severely cut hand while he was trying to repair a roof that was being torn from a building. At Stapleton International Airport…northwest winds gusted to 41 mph.

In 2001…west-northwest winds gusting as high as 54 mph warmed the temperature to a high of 70 degrees at Denver International Airport.

22-23

In 1914…post-frontal rain changed to snow. Precipitation totaled 2.72 inches…most of which was in the form of moist snow which melted as it fell in the business section of the city. About 3 inches of snow was measured on lawns in the residential areas on the morning of the 24th. Official snowfall totaled only 0.4 inch downtown… But an estimated 8.0 inches of snow melted as it fell. North to northeast winds were sustained to 29 mph with gusts to 30 mph on both days.

In 1975…a vigorous cold front moving across metro Denver followed by strong northeast winds gusting to 52 mph produced billows of blowing dust and plunged the temperature 21 degrees in an hour. The surface visibility was reduced to 1/4 mile in blowing dust at Stapleton International Airport. The temperature cooled from a daily record high of 81 degrees to a low of 38 degrees by day’s end. The first snowfall of the season totaled 2.7 inches on the 23rd. This was the only measurable snow of the month at Stapleton International Airport.

In 1995…heavy snow fell on the Palmer Ridge south of Denver and in the foothills west of Denver where snow amounts ranged from 4 to 8 inches. Sedalia…south of Denver… Received 8 inches of snow. Winds strengthened on the plains and produced blizzard conditions…reducing surface visibilities to less than 1/4 mile. I-70 was closed from just east of Denver at Gun Club Road to the Kansas border. Ten inches of snow fell at Strasburg east of Denver where north winds at sustained speeds of 35 to 45 mph with gusts as high as 60 mph produced 2 to 4 foot drifts. Snowfall totaled only 2.2 inches at the site of the former Stapleton International Airport. North winds gusted to 51 mph at Denver International Airport.

Continue reading October 20 to October 26: This Week in Denver Weather History

October 13 to October 19: This Week in Denver Weather History

This Week in Denver Weather History

Certainly snow begins to enter the equation as we get further into the season and our look back at Denver weather history for the week shows many such notable events. Others including damaging winds and even a tornado and monstrous hail storm.

From the National Weather Service:

11-13

In 1892…apparent post-frontal rainfall totaled 3.33 inches in downtown Denver over the 3 days. A trace of snow on the 12th melted as it fell. Rainfall of 2.58 inches on the 12th into the 13th was the greatest 24-hour precipitation ever recorded during the month of October. Northwest winds were sustained to 48 mph with gusts as high as 55 mph on the 12th.

12-13

In 2001…overnight peak wind gusts to 82 mph and 70 mph were measured atop Niwot Ridge and Squaw Mountain… Respectively.

12-14

In 1969…record breaking extremely cold temperatures for so early in the season occurred. The high temperature of 26 degrees on the 13th was two degrees lower than the previous record minimum temperature of 28 degrees for the date set in 1885. The high temperature of 24 degrees on the 12th exceeded the record low temperature (22 degrees set in 1885) for the date by only 2 degrees. In addition… 3 new record low temperatures for the dates were set. The low temperature dipped to 10 degrees on the 12th breaking the old record (22 degrees in 1885) by 12 degrees. On the 13th the mercury plunged to a low of 3 degrees breaking the old record (28 degrees in 1885) by 25 degrees. On the 14th the temperature reached a minimum of 4 degrees breaking the old record (25 degrees in 1966) by 21 degrees.

13

In 1990…strong downslope winds stirred up clouds of dust and gravel…rattled windows…and stripped autumn-colored leaves from trees in Boulder. A wind gust to 78 mph was clocked in southwest Boulder…while a 96 mph gust was recorded in northwest Boulder. West winds gusted to only 36 mph at Stapleton International Airport.

13-14

In 1910…light smoke from nearby forest fires drifted over the city.

In 1966…the first measurable snow of the season caused widespread damage to trees and shrubs. The heavy wet snow totaled 6.9 inches at Stapleton International Airport where north-northwest winds sustained at 20 to 25 mph and gusting to 45 mph caused much blowing and drifting snow. South and east of Denver…up to a foot of snow fell. Heavy wet snow accumulations followed by freezing temperatures and strong winds resulted in extensive damage to trees…cars… And utility lines by falling limbs. A woman was killed by a falling snow laden tree limb in Denver. Several other people received minor injuries from falling tree limbs.

In 1987…rain drenched metro Denver. The South Platte Canyon area southwest of Denver received the most with 1.11 inches at Kassler and 1.49 inches upstream at Strontia Springs. At Stapleton International Airport…0.62 inch of rain was measured…northwest winds gusted to 29 mph…and thunder was heard.

In 2007…a new 24-hour record of 2.65 inches of precipitation was set at Denver International Airport for the month of October; breaking the previous record of 2.58 inches set in 1892.

13-16

In 1873…smoke from several large forest fires in the mountains made the air very hazy in the city.

14

In 1952…the first measurable snowfall of the season left 1.2 inches of snow at Stapleton Airport. North winds gusted to 38 mph.

In 1974…rain changed to snow early in the day…but snowfall totaled only 1.0 inch at Stapleton International Airport where northeast winds gusted to 20 mph.

In 2021…very strong wind gusts developed over the higher mountain areas. Peak wind gusts atop Berthoud Pass ranged from 90 to 104 mph. At Denver International Airport…a peak wind gust to 41 mph was observed from the northwest.

15

In 1871…a terrible wind occurred during a snow storm in the foothills above Boulder. Damage was minor.

In 1878…high winds reached sustained speeds of 60 mph at times.

In 1911…post-frontal northwest winds were sustained to 41 mph with gusts to 43 mph.

In 1948…strong winds struck the Boulder area. Winds averaged 50 mph at Valmont just east of Boulder. Wind gusts in excess of 60 mph were recorded at the Boulder airport. Wind gusts to 40 mph briefly reduced the visibility to 1 1/2 miles in blowing dust at Stapleton Airport.

In 1980…a rare October tornado touched down in Boulder… Damaging a vocational training building and throwing three nearby cars together damaging them extensively. A mile and half away several camper vehicles were thrown 200 feet. The storm also produced 1 inch diameter hail in the Boulder area.

15-16

In 1928…a thunderstorm produced hail shortly after midnight on the 15th. Rain changed to snow by evening. Through the afternoon of the 16th…the heavy snowfall totaled 7.3 inches in the city. North winds were sustained to 23 mph on the 15th.

In 1984…the heaviest October snowstorm in several years hit eastern Colorado with a vengeance. The storm was known as the “Bronco Blizzard” since it occurred during a nationally televised Monday Night Football game in Denver. One to two feet of snow fell near the foothills in west metro Denver with 2 to 3 feet in the foothills. Wind gusts up to 55 mph whipped the snow into drifts as high as 4 feet. The storm closed schools…roads…and airports. I-70 was closed both east and west of Denver. I-25 was closed south to Colorado Springs. Flights were delayed for several hours at Stapleton International Airport. Power outages were widespread. Snowfall totaled 9.2 inches at Stapleton International Airport where north winds gusting as high as 40 mph caused frequent surface visibilities of 1/4 to 1/2 mile in moderate to heavy snow and blowing snow overnight. The high temperature of only 35 degrees on the 15th was a record low maximum for the date.

Continue reading October 13 to October 19: This Week in Denver Weather History

October 6 to October 12: This Week in Denver Weather History

This Week in Denver Weather History

Wind is arguably one of the most annoying weather conditions and as our look back at this week in Denver weather history shows, it is often present this time of year. We also notice some decent shots of snow, including one in 2005 that brought nearly a foot to the Mile High City.

From the National Weather Service:

6

In 1900…northwest winds were sustained to 40 mph with gusts as high as 50 mph in downtown Denver.

In 1903…northwest winds were sustained to 40 mph with gusts to 50 mph. The strong winds warmed the temperature to a high of 71 degrees in the city. The low reading was only 46 degrees.

In 1910…light smoke from forest fires drifted over the city.

In 1976…an arctic cold front brought light snow over the foothills above 6 thousand feet. Traffic was snarled at many locations. Only a trace of snow fell at Stapleton International Airport where rainfall totaled 0.20 inch and northeast winds gusted to 41 mph.

In 1991…the brilliant orange sunset was apparently the result of an extensive volcanic smoke layer in the upper atmosphere.

In 1994…strong west to northwest winds developed in the foothills above 9500 feet. A wind gust to 78 mph was recorded atop squaw mountain west of Denver and to 72 mph at Ward northwest of Boulder. Northwest winds gusted to 35 mph at Stapleton International Airport.

In 2011…strong winds developed in and around the Denver area ahead of an approaching storm system. At the National Wind Technology Center…peak wind gusts ranged from 79 to 92 mph during the early morning hours. Across metro Denver…the strong winds toppled a few trees and damaged patio furniture. The wind caused a few flight delays at Denver International Airport due to a partial ground stoppage of incoming flights. Peak wind reports also included: 66 mph at Cedar Point…63 mph at Denver International Airport…60 mph at Buckley Air Force Base; 59 mph at Highlands Ranch; 58 mph at Deer Trail and Rocky Mountain Metro Airport in Broomfield; 55 mph at Bennett…Centennial Airport and City Park in Denver.

7

In 1903…north winds were sustained to 40 mph with gusts to 48 mph.

In 1917…post-frontal northwest winds were sustained to 45 mph with gusts to 52 mph. Rain was mixed with a trace of snow…the first of the season. Precipitation totaled 0.22 inch and included the occurrence of hail… Even though no thunder was heard.

In 1950…strong winds caused a power outage in Boulder. This was the heaviest windstorm since January. Damage was minor. Northwest winds gusted to only 35 mph at Stapleton Airport.

In 1985…strong Chinook winds buffeted the Front Range foothills. Wind gusts between 60 and 70 mph were reported in Boulder and atop Squaw Mountain west of Denver. Southwest winds gusted to 41 mph at Stapleton International Airport.

7-8

In 1990…the season’s first snow occurred. Snowfall amounts varied from 3 to 7 inches across metro Denver. Snowfall totaled 4.0 inches at Stapleton International Airport where north winds gusted to 29 mph.

8

In 1923…southeast winds were sustained to 44 mph with gusts to 47 mph. The strong winds persisted through the afternoon. The high temperature of 77 degrees was the warmest of the month that year.

In 1975…a wind gust to near 100 mph was recorded in Boulder. Frequent wind gusts to 60 mph were reported along the foothills causing only minor damage. West winds gusted to 45 mph at Stapleton International Airport.

8-9

In 2017…an early season snowstorm produced heavy wet snow which broke branches and downed power lines. About ninety-eight thousand outages occurred in Denver and the surrounding metro area. Almost half the outages were very short…while 54210 were sustained outages that lasted longer than five minutes. Some however lasted for several hours. Snow amounts varied greatly along the Interstate 25 Corridor. West of I-25…storm totals included: 7.5 inches in Arvada…7 inches in Broomfield…6 inches Boulder and Louisville…with 5 inches at Ralston Reservoir. East of I-25…storm totals ranged from a trace to 4 inches. In the mountains and foothills…storm totals included: 12.5 inches near Genesee…10 inches at Eldorado Springs… Idledale and Nederland…with 8.5 inches near Jamestown.

9

In 1910…light smoke from forest fires in the mountains was sighted over the city.

In 1982…northwest winds gusted to 49 mph at Stapleton International Airport.

9-10

In 2005…a major winter storm brought heavy…wet snowfall to the Front Range mountains…eastern foothills…portions of metro Denver…and the palmer divide. Snow accumulations ranged from 8 to 26 inches with drifts from 3 to 4 feet in places. The heaviest snow occurred to the east and southeast of the city…closing most major highways in that area…including I-70 from Denver to Limon. The Red Cross opened four shelters for people who were stranded along I-70 in eastern Colorado. Since many trees had not yet shed their leaves…the storm caused significant tree damage. One woman in Denver was killed when a tree branch… 8 to 10 inches in diameter…snapped under the weight of the heavy…wet snow and struck her as she was shoveling her driveway. Xcel Energy reported power outages to about 35 thousand customers. Several incoming flights were delayed at Denver International Airport. Snow totals included: 16 inches in the foothills near Boulder…12 inches at Genesee and near Golden…22 inches near Watkins…19 inches near Bennett…17 inches southeast of Aurora…14 inches near Parker…13 inches near Castle Rock…12 inches in Centennial… 11 inches in Parker…and 10 inches at Denver International Airport and in Littleton. While many areas of metro Denver received heavy snow…others experienced almost entirely rain. This included west and northwest metro Denver…Boulder…and Longmont. Rainfall amounts were significant as storm totals ranged between 1.50 and 2.50 inches. The steady rainfall triggered 3 rockslides in foothills canyons. Two of the slides occurred on State Highway 119 in Boulder Canyon and the longest slide…7 feet in length…on State Highway 74 in Bear Creek Canyon at Idledale. North winds were sustained to around 23 mph with gusts to 31 mph at Denver International Airport on the 9th. The high temperature of only 34 degrees on the 10th was a record low maximum for the date. The low temperature on both days was 32 degrees.

In 2019…a vigorous winter like storm system brought intense northerly winds and the cold front blasted through the urban corridor. Peak wind gusts from 50 to 60 mph accompanied the front. Some trees in Denver were uprooted by the strong winds. Light rain and drizzle overnight…changed over to the season`s first snow during the predawn hours of the 10th. Bands of moderate to heavy snow brought 2 to 6 inches of snow in the Front Range mountains…foothills and urban corridor. The morning commute was especially hazardous as falling temperatures froze wet roads. Multiple crashes occurred including: I-25 in Denver…I-70 from Denver west to the Eisenhower Tunnel and State Highway 285 towards Fairplay. Over 300 crashes were reported in Denver and Aurora alone. After reaching a maximum temperatures of 83 degrees on the afternoon of the 9th…the temperature plummeted to 13 degrees on the 10th. A temperature change of 70 degrees…the second largest 2-day swing for the month of October in Denver weather history.

Continue reading October 6 to October 12: This Week in Denver Weather History