December can of course be cold and that is why Chinook winds are sometimes welcomed as they bring warm air to the Front Range.  However, those winds can also cause a great deal of damage if they blow too hard and we see that in our look back at this week in Denver weather history.  Particularly notable were winds on December 14th & 15th which caused accidents, toppled power poles and fences, ripped off roofs and more.

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.

9-13

In 1961…cold arctic air produced a protracted cold period. The temperature plunged to 16 degrees below zero on the 10th…establishing a new record for the date and the coldest reading since 25 degrees below zero on February 1… 1951.  Low temperatures dipped below zero on 5 consecutive days with 9 degrees below zero on the 9th…16 below on the 10th…10 below on the 11th…and 12 below on both the 12th and 13th.  High temperatures reached only 3 degrees on the 10th and 6 degrees on the 11th.

11-13

In 1940…5.4 inches of snow fell across downtown Denver. This was the only snowfall of the month.  Temperatures were quite cold on the 13th with a high of 6 degrees and a low of 2 degrees below zero.

In 1984…up to 6 inches of new snow fell over metro Denver… Hampering flight operations at Stapleton International Airport where snowfall totaled 3.8 inches and east winds gusted to 25 mph on the 11th.

12-13

In 1916…snowfall totaled 5.7 inches in downtown Denver. Northeast winds were sustained to 27 mph with gusts to 28 mph on the 12th.

In 1992…an upslope snowstorm whitened metro Denver.  While snowfall totaled only 4.1 inches at Stapleton International Airport…7 inches of new snow fell in Morrison…with 12 inches measured in Castle Rock.  North winds gusted to 23 mph at Stapleton International Airport on the 13th.

In 1995…strong winds gusting to nearly 100 mph whipped across the foothills west of Denver.  The strongest wind gusts included 98 mph atop Squaw Mountain and 75 mph at the Eldora Ski Area.  West-northwest winds gusted to 41 mph at Denver International Airport on the 13th.

12-15

In 1921…downslope Chinook winds produced warm temperatures in the city…which resulted in 4 temperature records. High temperatures of 72 degrees on the 13th and 68 degrees on the 15th were record maximums for the dates.  Low temperatures of 47 degrees on both the 12th and 13th were record high minimums for the dates.  West winds were sustained to 38 mph on the 12th and to 25 mph on the 13th.

13

In 1955…strong winds raked the foothills.  A wind gust to 72 mph was recorded at rocky flats northwest of Denver.  Some damage occurred in Boulder.  Northwest winds were sustained to speeds of 23 mph at Stapleton Airport.

In 1988…high winds again occurred in Boulder where winds were clocked to 66 mph.  West winds gusted to 43 mph at Stapleton International Airport.
13-14 in 1902…heavy snowfall totaled 6.4 inches in the city overnight.  North winds were sustained to 18 mph with gusts to 20 mph on the 13th.

In 1925…heavy apparent post-frontal snowfall totaled 7.8 inches across downtown Denver.  Northwest winds were sustained to 34 mph with gusts to 42 on the 13th… And north winds were sustained to 33 mph with gusts to 38 mph on the 14th.

In 1951…heavy snowfall totaled 5.9 inches at Stapleton Airport.

In 1987…a snowstorm dropped 2 to 8 inches of snow along the Front Range foothills.  Eight to 12 inches fell just south of Denver.  Icy streets and highways contributed to many traffic accidents across metro Denver and flights were delayed at Stapleton International Airport where 2.7 inches of snow fell and northeast winds gusted to 17 mph.

In 1991…high winds pummeled metro Denver.  Wind gusts to 93 mph were recorded at Rollinsville.  Wind speeds across metro Denver were generally 35 to 50 mph.  Northwest winds gusted to 48 mph at Stapleton International Airport on the 13th.

14

In 1926…an intrusion of cold air resulted in temperatures remaining below zero.  The high temperature of one degree below zero was a record low maximum for the date.  The low temperature was 11 degrees below zero.  North winds were sustained to 17 mph.

In 1985…a wind gust to 61 mph was recorded at Table Mesa in Boulder.

In 1996…high winds gusting from 60 to nearly 80 mph moved off the Front Range foothills and over the northeast Colorado plains in the wake of a fast moving cold front. The strongest wind gusts included 79 mph at Golden gate canyon and 70 mph near Table Mesa in southwest Boulder. At Denver International Airport…west-northwest winds gusted to only 39 mph.

14-15

In 1988…a snow storm again whitened metro Denver. Snowfall along the Front Range was in the 6 to 12 inch range.  Snowfall totaled 5.8 inches at Stapleton International Airport where north winds gusted to 38 mph.

In 1990…high winds howled across metro Denver behind a strong pacific cold front.  Boulder was hardest hit by the high winds.  A wind gust to 120 mph was recorded in south Boulder where winds stripped the roof off a garage…a vacant gas station…and a house under construction. Elsewhere in Boulder…several trees were blown down.  In Boulder canyon…the winds toppled two cinder block walls on a house under construction.  Four Boulder County women were treated for injuries caused by the wind.  The injuries were confined to a broken wrist…a mild concussion…bruises…and facial cuts.  Two semi-tractor trailers were blown over by the fierce winds south of Boulder.  Another truck rollover occurred southeast of Golden.  Drivers of all three trucks suffered only cuts and bruises.  Several vehicles were trapped in a blinding dust storm on the Denver-Boulder Turnpike near Broomfield.  Drivers were forced to stop along the highway for several minutes during the storm and witness their vehicles being pelted with sand and gravel. A wind gust to 97 mph was recorded in Golden.  High winds were also reported in Arvada…Boulder…and Lakewood.  Winds toppled a number of utility poles and wooden fences…blew out windows…and caused structural damage to a large apartment complex on the west side of Golden.  Wind gusts of 70 to 100 mph caused considerable damage to several large billboards north of Golden…as well as damaging the paint…trim…and glass on numerous vehicles in the area. A west wind gust to 51 mph was recorded at Stapleton International Airport.

15

In 1999…high winds developed in and near the foothills as a strong upper level jet moved into the area.  Although most wind gusts were in the 70 to 80 mph range…a weather spotter located 1 mile south of Fritz Peak near Rollinsville measured a peak wind gust to 124 mph.  Other wind reports included wind gusts to 77 mph at the National Center for Atmospheric Research in Boulder and atop Blue Mountain and 70 mph at the national wind technology center on Rocky Flats south of Boulder.  West winds gusted to only 32 mph at Denver International Airport.

In 2000…high winds developed in the foothills of Boulder County…but winds were strong across all of metro Denver. Winds gusted as high as 72 mph at the National Center for Atmospheric Research on the mesa just southwest of Boulder. West winds gusted to 44 mph at Denver International Airport.

15-16

In 1964…high winds raked metro Denver…causing considerable damage.  Wind gusts to 81 mph were recorded at rocky flats northwest of Denver…94 mph at Jefferson County airport near Broomfield…48 mph in downtown Boulder…and 70 mph in Littleton.  West wind gusts to 67 mph were recorded at Stapleton International Airport.  A man working on construction in downtown Denver died from injuries after being struck by a 5-foot by 8-foot section of plank runway blown by the strong winds.  Several people were blown down by the strong winds or hit by flying objects.  Buildings… Roads…trees…and power equipment were damaged.  Roads were closed east of Denver due to blowing dust.

In 1981…wind gusts to 60 mph were common in the foothills northwest of Denver.  West wind gusts to 47 mph were recorded at Stapleton International Airport where the visibility was briefly reduced to 3 miles in blowing dust.

In 1996…strong pre-frontal winds developed in the foothills of Boulder County ahead of an arctic cold front that moved into northeastern Colorado late on the morning of the 16th. Wind gusts of 70 to 75 mph were clocked at Table Mesa in southwest Boulder.

16

In 1912…northwest winds were sustained to 44 mph with an extreme velocity of 45 mph.

In 1921…north winds were sustained to 46 mph with gusts to 50 mph behind a vigorous cold front.  Only a trace of snow fell.

In 1954…a vigorous cold front produced sustained north winds to 45 mph with gusts as high 54 mph.  Visibility was reduced to 1 mile in blowing dust at Stapleton Airport.

In 1955…sustained west winds to 44 mph with gusts as high as 58 mph were recorded at Stapleton Airport.

In 1994…a wind gust to 108 mph was recorded atop Squaw Mountain west of Denver with a gust to 92 mph in Rollinsville southwest of Boulder.  West winds gusted to 48 mph at Stapleton International Airport.

In 1996…a vigorous arctic cold front moved across metro Denver.  Heavy snow and strong winds accompanied the front as near whiteout conditions in snow and blowing snow developed suddenly.  Northerly winds gusted from 40 to 60 mph behind the front.  Dozens of accidents occurred as roads and highways quickly turned to a glaze of ice.  Snowfall amounts ranged from 4 to 6 inches across metro Denver and in the foothills.  The exception was at Eldorado Springs south of Boulder where 8 inches of new snow were measured.  Snowfall totaled only 1.8 inches at the site of the former Stapleton International Airport. Officially…this was the only measurable snow of the month in Denver.  At Denver International Airport…north winds gusted to 34 mph.

In 1999…another brief round of high winds developed in and near the foothills of Boulder County.  Peak wind gusts included 83 mph at the National Center for Atmospheric Research near Boulder and 74 mph atop Niwot Ridge and at the National Wind Technology Center on Rocky Flats south of Boulder.  West winds gusted to only 33 mph at Denver International Airport where the temperature warmed to a high of 54 degrees.

In 2000…high winds in the mountains spread into the foothills west of Denver.  Winds gusted to 87 mph at Georgetown Lake and at the National Center for Atmospheric Research in Boulder.  Winds gusted to 72 mph at the national wind technology center south of Boulder.

16-17

In 1908…heavy snowfall totaled 7.9 inches in downtown Denver where north winds were sustained to 20 mph on the 17th.  Temperatures were in the teens and 20’s.

In 1939…low temperatures of 49 degrees on the 16th and 43 degrees on the 17th were record high minimums for the dates.  High temperatures of 65 on the 16th and 72 on the 17th were not records.

In 1980…Chinook winds blew through the night in Boulder with a peak reported gust to 75 mph.  Northwest winds gusted to 30 mph at Stapleton International Airport on the 17th. The strong Chinook winds warmed temperatures to record daily highs of 70 degrees on the 16th and 73 degrees on the 17th.

In 2016…the presence of a warm and moist southwesterly flow aloft…overrunning an Arctic airmass with shallow post frontal upslope produced a band of very heavy snowfall across the Denver metro area. The enhanced band of heavy snow extended west into the Front Range mountains and foothills with snowfall rates up to 2 inches per hour. Multiple accidents occurred during the evening hours of the 16th as the snow quickly piled up. Three hundred flights were canceled at Denver International Airport as the winter storm moved through the Denver metro area early morning hours of the 17th. Storm totals in the Front Range mountains and foothills included: 16 inches at Loveland Ski Area; 12 inches near Conifer…11 inches at Winter Park Ski Area…10.5 inches at Bergen Park… 10 inches at Echo Lake…with 9.5 inches at Aspen Springs and Evergreen. In and around metro Denver…storm totals included: 11.5 inches in Wheat Ridge…11 inches in Arvada… 9 inches near Morrison…8 inches at Denver International Airport…Denver/Stapleton…Marston Reservoir and Ralston Reservoir; 7.5 inches in Westminster; 6.5 inches…5 miles northeast of Westminster; 6 inches in Aurora…5 miles west-northwest of Brighton…Englewood and near Louisville.

17

In 2000…high winds gusting from 60 to 74 mph howled across the northeast plains of Colorado.  In Parker where winds gusted to 60 mph…a 20-foot by 40-foot piece of roof was ripped from a building.  West winds gusted to 53 mph at Denver International Airport.  This was the highest wind gust of the month at the airport.  An intense…but very localized wind gust to 112 mph was measured near Georgetown Lake in the foothills west of Denver.

17-24

In 1924…a prolonged cold spell occurred after mild temperatures during the first half of the month.  Most low temperatures dipped below zero with the coldest reading of 15 degrees below zero occurring on the 24th. The high temperature of only 5 degrees on the 18th was a record low maximum for the date.

18

In 1901…north winds were sustained to 52 mph with gusts to 58 mph behind an apparent cold front.

In 1973…a brief blizzard dumped heavy snow across metro Denver.  Snowfall totaled 9.2 inches at Stapleton International Airport where north winds gusting to 53 mph produced much blowing snow.  The storm forced many schools and businesses to close.

In 1996…a homeless man in Denver was found unconscious in his car suffering from exposure.  The man’s body temperature was only 85 degrees when he was discovered.  He died several hours later.  Early morning temperatures had dipped to 9 degrees below zero.

In 1999…high winds were reported for a brief time in the foothills.  Winds gusted to 72 mph in Golden gate canyon and to 71 mph at the National Center for Atmospheric Research in the foothills southwest of Boulder.  West winds gusted to only 39 mph at Denver International Airport where the temperature warmed to a high of 53 degrees.

In 2002…only a trace of snow fell at the site of the former Stapleton International Airport.  This…along with the trace of snow on the 5th…was the only snow of the month…ranking the month the 2nd least snowiest on record.

18-19

In 2012…a storm system brought moderate to heavy snow to the mountains and foothills west of metropolitan Denver and blizzard conditions to plains east of Denver metro area. The combination of snow and wind reportedly reduced visibility to just a few hundred feet at times…and resulted in several road closures including Interstate 70 east of Aurora. East of Denver gusty northerly winds ranged from 35 to 55 mph produced extensive blowing and drifting snow…ranging from 1 to 4 feet in depth. Storm totals ranged from 3 to 5 inches. In the mountain and foothills…the heaviest snowfall occurred along and north of I-70 and included: 12 inches at Genesee…9 inches near Eldorado Springs; 8.5 inches at Coal Creek Canyon…8 inches near Evergreen… With 6 inches at Eldora Ski Area…Idaho Springs… Gross Reservoir and Nederland. At Denver International Airport…1.7 inches of snowfall was observed. In addition…a peak wind gust to 35 mph was observed from the north on the 19th.

18-21

In 2010…a winter storm produced a 4-day period of moderate to heavy snow in the mountains. The combination of strong wind and heavy snow forced the closure of several mountain passes due to the threat of avalanches. The Amtrak train route… Which runs from Denver to California…was rerouted through Wyoming when Union Pacific closed its tracks along Interstate 70. Numerous accidents forced the closure of I-70 at times. The wind gusted to 60 mph over the higher mountain passes. Storm totals in the ski areas west of Denver ranged from 16 to 32 inches.

18-24

In 1998…a vigorous cold front with north winds gusting as high as 38 mph at Denver International Airport on the 18th dropped temperatures from a high of 51 degrees to a low of just 6 degrees before midnight.  The arctic air mass that settled over metro Denver produced intermittent light snow and a week-long protracted cold spell that caused low temperatures to plunge well below zero for 6 consecutive nights.  The coldest temperature was 19 degrees below zero on the morning of the 22nd.  High temperatures climbed only into the single digits on 4 consecutive days…from the 19th through the 22nd.  At least 15 people…mostly homeless… Were treated for hypothermia at area hospitals.  The bitter cold weather was responsible…either directly or indirectly… For at least 5 fatalities.  Three of the victims died directly from exposure.  The cold weather also caused intermittent power outages.  Following the cold snap… Thawing water pipes cracked and burst in several homes and businesses…causing extensive damage.  Only one temperature record was set.  The high temperature of only 7 degrees on the 19th set a record low maximum for the date.

19

In 1913…post-frontal heavy snowfall totaled 8.5 inches over downtown Denver.  North winds were sustained to only 16 mph.

In 1994…an intense pacific storm system and associated cold front moved across Colorado early in the day.  Strong downslope winds buffeted the Front Range eastern foothills. The highest wind gust recorded was 92 mph at rocky flats in northern Jefferson County.  Most of the wind gusts during the day ranged from 63 to 86 mph with lighter gusts of 40 to 58 mph on the northeast plains.  The strong winds downed power lines and poles in south Lakewood…causing power outages to 2400 homes.  Other small power outages and surges occurred across metro Denver.  Northwest winds gusted to 43 mph at Stapleton International Airport.

19-20

In 1982…high winds buffeted the eastern foothills.  At midday on the 19th…gusts of 75 to 80 mph were recorded in the Table Mesa area of Boulder.  A gust to 62 mph was clocked in Boulder on the evening of the 20th.

In 1989…strong winds howled at mountain top level in clear creek and Gilpin counties.  Speeds reached 97 mph on the summit of Squaw Mountain and 84 mph one mile south of Rollinsville.  Northwest winds gusted 35 mph at Stapleton International Airport on the 20th.

19-23

In 1990…a surge of very cold arctic air invaded metro Denver.  Many temperature records were broken as the mercury remained at or below zero for 85.5 hours at Stapleton International Airport…making it the third longest period of subzero readings in 118 years of record keeping.  On the morning of the 22nd…the mercury plunged to 25 degrees below zero…which equaled the all time record low temperature for the month set on December 24…1876. In the foothills southwest of Denver at tiny town…the mercury plunged to 33 degrees below zero on the morning of the 21st.  On the same morning at Castle Rock the temperature dipped to 26 degrees below zero.  During the period…other daily temperature records were set at Denver…including:  record low maximum of 3 degrees below zero on the 20th and a record low of 17 degrees below zero on the 23rd.  The record low was equaled with 16 degrees below zero on the 20th and 21 degrees below zero on the 21st.  Snowfall totaled 2.7 inches at Stapleton International Airport from the 19th through the 21st.