Tag Archives: December Weather

December 13 to December 19: This week in Denver weather history

This Week in Denver Weather History

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.

Continue reading December 13 to December 19: This week in Denver weather history

December 6 to December 12: This week in Denver weather history

This Week in Denver Weather History

Denver and Colorado are certainly known for their varied weather conditions and as always, looking back at the weather history books highlights that.  On these dates we have seen Arctic cold and balmy temperatures in the 70’s.  We have seen hurricane force winds and even a rare December thunderstorm.  And as one would expect, there has been plenty of snow.

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.

4-6

In 1960…heavy snowfall totaled 12.0 inches over the 3 days with 5.1 inches on the 4th…5.2 inches on the 5th…and 1.7 inches on the 6th.  Rain changed to snow early on the 4th and ended by early afternoon.  Snow started again early on the 5th and continued through midday on the 6th.  West northwest winds gusted to 30 mph on the 4th.  Post cold frontal temperatures cooled from a high of 38 degrees on the 4th to a low of 7 degrees below zero on the 6th.

5-6

In 1883…a major snow storm hit the city.  Heavy snow fell from 10:00 am on the 5th to 7:30 am on the 6th.  The amount of snowfall was not recorded…but precipitation from melted snow totaled 1.75 inches…which would give an estimated snowfall of nearly 18 inches.  Temperatures during the storm were in the 30’s…so some of the snow May have melted as it fell.  However…railroads were blocked and telegraph lines were downed in all directions.  Telephone wires and poles were nearly all broken down.  The company manager estimated the damage at 30 thousand dollars.  Northeast winds were sustained to 24 mph in the city.

In 1892…heavy snow totaled 6.2 inches in downtown Denver. Most of the snow…6.0 inches…fell on the 6th.

In 2001…high winds developed in the foothills northwest of Denver.  Winds gusted to 74 mph at aspen springs.  West- northwest winds gusted to 35 mph at Denver International Airport…where the temperature warmed to a high of 55 degrees on the 6th.

5-7

In 1978…a major storm dumped heavy snow across metro Denver. At Stapleton International Airport…snowfall totaled 8.5 inches…northeast winds gusted to 46 mph…and temperatures plunged from a high of 49 degrees on the 5th to a low of only 6 degrees on the 6th.  Maximum temperature of 6 degrees on the 7th was a new daily record low maximum reading.  Most of the snow…6.7 inches…fell on the 5th.

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.

6

In 1939…high temperature of 73 degrees was a record maximum for the date.  Low temperature of 44 degrees was a record high minimum for the date.

In 1967…strong west winds produced blowing dust at Stapleton International Airport where a wind gust to 55 mph was recorded.  A heavy windstorm caused minor damage in Boulder. In Denver…some structural panels were blown from a building… And the screen of an outdoor theater was severely damaged. There were unofficial reports of wind gusts to 75 mph in metro Denver.

In 1977…wind gusting to 85 mph raked the foothills from Boulder to Morrison.  A few houses under construction were blown down.  Northwest winds gusted to 39 mph at Stapleton International Airport.

In 1991…high in the atmosphere…a volcanic ash cloud was clearly visible in the direction of the sun during the late morning and early afternoon.

6-7

In 1953…high winds buffeted the eastern foothills.  Wind gusts to 80 mph occurred on Lookout Mountain.  In Denver winds gusted to 65 mph.  Damage in Boulder totaled 15 hundred dollars.

7

In 1897…west winds were sustained to 53 mph with gusts to 66 mph.  The Chinook winds warmed the temperature to a high of 62 degrees…the warmest day of the month.

In 1957…a vigorous cold front produced a dust storm as it moved south across metro Denver.  West-northwest wind gusts to 59 mph were recorded at Stapleton Airport where the surface visibility was briefly reduced to 1/2 mile in blowing dust.  Light snowfall of only 0.8 inch followed the passage of a secondary Canadian cold front.

In 1958…the worst wind storm in several years caused 10 thousand dollars damage in Boulder where wind gusts were estimated to 75 mph.

In 1977 winds up to 115 mph were reported in the Boulder area where one house was unroofed and another damaged. One woman was knocked down by the wind and injured. Several families were evacuated from homes in Boulder. Damage to trailers and motor vehicles was widespread. West winds gusted to 54 mph at Stapleton International Airport where the Chinook winds warmed the temperature to a high of 64 degrees.

In 1987…strong winds buffeted the Front Range foothills. A peak gust to 93 mph was recorded at the National Center for Atmospheric Research in Boulder.  Nearby…a metal shed was blown over a fence into a tree two houses away.  Wind gusts of 70 to 80 mph were common in Boulder.

In 1988…4 to 8 inches of snow fell across metro Denver and caused traffic gridlock conditions on area highways.  The 3.9 inches of snow at Stapleton International Airport caused two-hour flight delays.  Northeast winds gusted to 25 mph.

In 2005…a brief cold snap resulted in record breaking temperatures.  The low temperature of 13 degrees below zero was a record minimum for the date.  The high temperature of only 3 degrees was a record low maximum for the date.  The cold temperatures were accompanied by 1.4 inches of light snow that was measured at Denver Stapleton overnight on the 6th and 7th.

Continue reading December 6 to December 12: This week in Denver weather history

Thornton’s December weather preview: Winter arrives in earnest

Thornton, Colorado's December Weather Preview

Recent months have, overall, been warmer and drier than normal.  Last month continued that trend.  What will December hold for us?

The month of December brings with it the official start of winter and oftentimes, colder and snowier weather conditions.

It however can also offer unseasonably warm temperatures and bone dry conditions.  Given our recent mild and dry weather, we are certainly hoping for a change in the coming month.

Overall December’s monthly mean temperature of 30.0 degrees (1981 – 2010 averages) makes it our coldest month.  Snow is always on everyone’s mind this time of year but December is only our 3rd snowiest month behind March and November with an average of 8.5 inches of the white stuff.

Get all the details on Thornton’s December weather including a look back at historical events and a look at the long range forecast in our December weather preview here.

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November 29 to December 5: This week in Denver weather history

This Week in Denver Weather History

As always, our look back at Denver’s weather history books is very eventful.  As we start to get closer to winter, we begin to see many more multi-day snow events that are notable and this week’s look is no different.  We see many major snow events and also of note are the damaging high wind events.

From the National Weather Service:

25-29

In 1985…dense fog with visibilities as low as 1/8 mile occurred on five consecutive days at Stapleton International Airport.  The fog was at times accompanied by light snow… Light freezing drizzle…or ice crystals.  Fog occurred all day on both the 26th and 29th.
28-29 in 1908…heavy snowfall overnight and for most of the day on the 29th totaled 12.5 inches.  Precipitation was 1.09 inches.  Northwest winds were sustained to 26 mph on the 29th.

In 1928…a major storm dumped 15.5 inches of snowfall on downtown Denver.  North winds were sustained to 18 mph with gusts to 19 mph on the 28th.

In 1992…an upper level storm system moved across metro Denver…but left only a dusting of snow.  Snowfall totaled only 1.6 inches at Stapleton International Airport where north winds gusted to 25 mph.  Other snow amounts included: 8 inches at Conifer…6 inches at Lake Eldora…3 inches at Rollinsville and in southeast Denver.

In 1997…a storm system tracking across northern New Mexico produced strong north to northeast upslope flow against the eastern slopes of the Front Range and Palmer Ridge. Snowfall totals in Jefferson County included:  14 inches near Deckers; 12 inches at Castle Rock and Sedalia; 10 inches near Conifer…11 miles southwest of Morrison…and at Buffalo Creek.  Elsewhere…snow accumulations were less. Snowfall totaled only 0.7 inch at the site of the former Stapleton International Airport on the 27th and 28th.

In 2004…heavy snow fell in the foothills and across metro Denver.  In the foothills…snowfall totals included:  13 inches at Roxborough State Park and Eldorado Springs… 11.5 inches near Conifer…11.0 inches near Nederland…and 10 inches near Indian Hills.  Across metro Denver snowfall totaled 14 inches near Sedalia…9 inches near Louisville… 8 inches at Ralston Reservoir…and 5.1 inches in the Stapleton area of Denver.  Northeast winds gusted to 28 mph at Denver International Airport on the 28th.

In 2006…a slow moving storm system brought heavy snow to the mountains and to the eastern foothills where snowfall ranged from 8 to 18 inches.  Some of the more impressive snow totals included:  18 inches at Genesee…17.5 inches near Boulder…17 inches at aspen springs…16.5 inches 10 miles northwest of Golden…15 inches at Eldorado Springs… 14.5 inches in Idaho Springs and near Jamestown…12 inches in grant and near Indian Hills…11.5 inches near Blackhawk… 11 inches at gross reservoir and Eldora…and 10.5 inches in Conifer.  Across metro Denver…storm total snowfall generally ranged from 5 to 9 inches with the heaviest amounts near the foothills in Boulder and Jefferson counties.  The most impressive totals included:  15.5 inches at Ken Caryl…12 inches in Boulder…7.5 inches near Morrison…and 7 inches near both Chatfield and Ralston reservoirs.  Snowfall totaled only 4.2 inches in the Denver Stapleton area.  Northeast winds gusted to 31 mph at Denver International Airport on the 28th.

28-30

In 1991…a winter storm dumped heavy snow in the foothills and near the Palmer Divide with 10 inches recorded at Conifer and Golden Gate Canyon…12 inches in Morrison… 6 inches at Castle Rock and Parker.  Only 3.4 inches of snow fell at Stapleton International Airport where north winds gusting to 35 mph on the 29th…produced some blowing snow.  Some light freezing drizzle also fell on the 28th and 29th.

29

In 1877…the all-time lowest recorded minimum temperature in the month of November…18 degrees below zero…occurred. The high temperature for the day was 16 degrees.

In 1899…northwest winds were sustained to 51 mph with gusts as high as 60 mph.  The Chinook winds warmed the temperature to a maximum of 74 degrees…a record high for the date and the warmest of the month that year.  The minimum temperature was only 39 degrees.

In 1927…post-frontal rain changed to snow and totaled 5.8 inches over downtown Denver.  Northeast winds were sustained to 22 mph.

In 1977…85 mph winds were reported at Wondervu in the foothills southwest of Boulder.  Northwest winds gusted to 39 mph at Stapleton International Airport.

In 1980 strong Chinook winds reached 85 mph in Boulder… Blowing traffic signals and street lights down.  Some windows were shattered by the wind.  West winds gusted to 37 mph at Stapleton International Airport.

In 1994…high winds blew across the Front Range eastern foothills.  Wind gusts to 92 mph occurred atop squaw mountain…5 miles south of Idaho Springs…and to 82 mph on fritz peak near Rollinsville in the foothills southwest of Boulder.  A wind gust to 75 mph was recorded at Jefferson County airport near Broomfield.  Northwest winds gusted to only 35 mph at Stapleton International Airport. No damage was reported.

29-30

In 2008…a storm system produced locally heavy bands of snow across Douglas…Elbert and eastern Jefferson counties. Northerly winds gusting to 50 mph caused snow drifts to pile up to 2 feet in depth.  Storm totals included:  12 inches just southwest of Kassler…11.5 inches…6.5 miles southwest of Castle Rock; 11 inches…8.4 miles southeast of Aurora and 9 miles west of Littleton; 10 inches at Louviers… 8 inches…2 miles west-southwest of Highlands Ranch and 5 miles south-southeast of Sedalia…and 7.5 inches…14 miles west-southwest of Agate and at Castle Pines.  At Denver International Airport…2 inches of snow was observed. North winds gusted to 46 mph on the 30th.

30

In 1899…west winds were sustained to 45 mph with gusts as high as 48 mph.

In 1903…west winds sustained to 44 mph with gusts to 54 mph warmed the temperature to a high of 57 degrees.

In 1981…strong winds blasted the foothills.  In Wondervu… Winds were clocked to 81 mph with many other locations in the foothills reporting over 60 mph.  Northwest winds gusted to 28 mph at Stapleton International Airport.

In 1986…the worst snow storm of the season dumped from 5.0 inches of snow at Stapleton International Airport to 14 inches over the higher southwestern suburbs.  On the Sunday after thanksgiving…one of the busiest travel days of the year at Stapleton International Airport…two of the four runways were closed and flights were delayed up to four hours.  Near-blizzard conditions prevailed on the plains east of Denver…closing both I-70 and I-76 for a time. North wind gusts to 36 mph were recorded at Stapleton International Airport.

In 2000…strong winds raked metro Denver.  In Thornton…a construction worker was critically injured when the scaffolding on which he was standing collapsed…throwing him 25 feet to the ground.  West winds gusted to 54 mph at Denver International Airport.

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.

Continue reading November 29 to December 5: This week in Denver weather history

December 2019 weather recap: Warmer than normal temps, little snowfall

We closed out 2019 with a change from the cool, wet conditions of the previous two months. December saw the opposite conditions as average temperatures were above normal and snow a rarity.

Storm systems did move through Colorado and the Rocky Mountain region and while the high country saw plenty of snow, these storms evaded the Front Range for most of the month. Temperatures were never particularly warm but overall, the average temp was warmer than normal in Thornton.

On the 5th of the month, we saw a respectable bit of rain instead of snow. Finally, a light snowfall on the 14th was the first snow of the month. We then stayed dry until the 28th when we received our first – and only – appreciable snowfall of the month.

Thornton’s overall average temperature for the month came in at 31.9 degrees. This was a good bit warmer than Denver’s long term average for December of 30.0 degrees. Out at Denver International Airport where the Mile High City’s official records are kept, it was warmer with an average of 33.7 degrees.

Temperatures in Thornton ranged from a high of 64.6 degrees on the 22nd down to a low of 7.2 degrees on the morning of the 30th. Denver recorded a maximum of 67 degrees and its minimum of 3 degrees on the same dates.

In terms of precipitation, Denver averages 0.35 inches during December. Thornton fell short of that with 0.28 inches while Denver had just a touch more with 0.30 inches.

A mere 2.8 inches of snow was recorded in Thornton during the month and Denver had an identical number. These were well short of the 8.7 inches December typically brings.

Click here to view Thornton’s December 2019 climate report.

Thornton, Colorado's December 2019 Temperature Summary. (ThorntonWeather.com)
Thornton, Colorado’s December 2019 Temperature Summary. (ThorntonWeather.com)
Thornton, Colorado's December 2019 Precipitation Summary. (ThorntonWeather.com)
Thornton, Colorado’s December 2019 Precipitation Summary. (ThorntonWeather.com)
CLIMATE REPORT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
851 AM MST WED JAN 1 2020

...................................

...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2019...

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2019

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH              79   12/05/1939
 LOW              -25   12/22/1990
                        12/24/1876
HIGHEST            67   12/22        62       5       63  12/21
LOWEST              3   12/30        -4       7        0  12/31
                        12/29
AVG. MAXIMUM     45.3              42.8     2.5     46.1
AVG. MINIMUM     22.1              17.1     5.0     18.8
MEAN             33.7              30.0     3.7     32.5
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      6               5.8     0.2        4
DAYS MIN <= 32     27              29.4    -2.4       31
DAYS MIN <= 0 0 2.0 -2.0 1 PRECIPITATION (INCHES) RECORD MAXIMUM 5.21 1913 MINIMUM 0.00 1881 TOTALS 0.30 0.35 -0.05 0.03 DAILY AVG. 0.01 0.01 0.00 0.00 DAYS >= .01         2               4.1    -2.1        1
DAYS >= .10         2               1.1     0.9        0
DAYS >= .50         0               0.1    -0.1        0
DAYS >= 1.00        0               0.0     0.0        0
GREATEST
 24 HR. TOTAL    0.18   12/28 TO 12/28           12/31 TO 12/31

SNOWFALL (INCHES)
RECORDS
 TOTAL            2.8               8.7
RECORD DECEMBER  57.4    1913

DEGREE_DAYS
HEATING TOTAL     964              1086    -122      999
 SINCE 7/1       2499              2468      31     2372
COOLING TOTAL       0                 0       0        0
 SINCE 1/1        916               769     147     1026

FREEZE DATES
RECORD
 EARLIEST     09/08/1962
 LATEST       06/08/2007
EARLIEST                        10/07
LATEST                          05/05
.................................................................

WIND (MPH)
AVERAGE WIND SPEED              9.1
RESULTANT WIND SPEED/DIRECTION   4/217
HIGHEST WIND SPEED/DIRECTION    33/350    DATE  12/28
HIGHEST GUST SPEED/DIRECTION    43/270    DATE  12/11

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR            7
NUMBER OF DAYS PC             19
NUMBER OF DAYS CLOUDY          5

AVERAGE RH (PERCENT)     56

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

December 2019 top shots: Monthly photo slideshow

Where the buffalo roam. December 1, 2019. (Patrick Martin)
Where the buffalo roam. December 1, 2019. (Patrick Martin)

The month of December can offer everything from bone dry conditions to bone chilling cold and monstrous snowstorms.  The weather and wildlife all afford an abundance of photo opportunities as our December photo slideshow shows.

Leaves have fallen from trees now and the landscape can sometimes look quite stark.  However it only takes a quick shot of snow to change that picture greatly.  Throw in gorgeous sunrises and sunsets, plenty of wildlife big and small, kids playing and much more and the month can be quite colorful and eventful.

  • Slideshow updated December 31, 2019
  • To learn more about how to send your photo to us for inclusion in the slideshow, see below the slideshow.

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather-related imagery.

Sunsets, sunrises, wildlife and of course every type of weather condition are vividly depicted in images captured from yours and our cameras.

[flickr_set id=”72157712158922803″]

What is missing in the slideshow above?  Your photo!

Our monthly photo slideshow is going to feature images that we have taken but more importantly images that you have captured.  The photos can be of anything even remotely weather-related.

Landscapes, current conditions, wildlife, pets, kids.  Whimsical, newsy, artsy.  Taken at the zoo, some other area attraction, a local park, a national park or your backyard.  You name it, we want to see and share it!

Images can be taken in Thornton, Denver or anywhere across the extraordinary Centennial State.  We’ll even take some from out of state if we can tie it to Colorado somehow.

We’ll keep the criteria very open to interpretation with just about any image eligible to be shown in our slideshows.

What do you win for having your image in our slideshow?  We are just a ‘mom and pop’ outfit and make no money from our site so we really don’t have the means to provide prizes.  However you will have our undying gratitude and the satisfaction that your images are shared on the most popular website in Thornton.

To share you images with us and get them included in the slideshow just email them to us or share them with ThorntonWeather.com on any of the various social media outlets.  Links are provided below.

So come on, get those camera’s rolling!

December 29 to January 4: This Week in Denver Weather History

This Week in Denver Weather History

The end of the year and beginning of the next can be an eventful period in terms of weather in the Denver metro area. Looking back at this week in Denver weather history there are certainly periods of cold and snow but perhaps most notable are the number of damaging wind events.

From the National Weather Service:

25-31

In 1980…temperatures were unusually warm during the week between Christmas and New Year’s. High temperatures for the week ranged from the mid-50’s to the mid-70’s. Four temperature records were set. Record highs occurred on the 26th with 68 degrees…the 27th with 75 degrees…and the 30th with 71 degrees. A record high minimum temperature of 41 degrees occurred on the 27th.

27-29

In 1983…a second surge of bitter cold air in less than a week was less intense. Record breaking low temperatures of 12 degrees below zero on the 28th and 15 degrees below zero on the 29th were accompanied by 3.7 inches of snowfall and northeast winds gusting to 23 mph.

28-29

In 1906…a trace of snow fell on both days…which along with a trace of snow on the 5th…was the only snow of the month…ranking the month the second least snowiest December on record.

In 1970…wind gusts to 87 mph were recorded at the National Center for Atmospheric Research in Boulder. Winds gusted to only 46 mph in downtown Boulder. Damage was minor.

In 2006…while metro Denver residents were still digging out from the heavy snowfall and blizzard that occurred on December 20-21…the second major winter storm in a week buried the city and the eastern foothills again in more deep snow. Heavy snowfall ranged from 1 to 2 1/2 feet in the foothills and from 6 to 18 inches across the city. Another slow moving storm system centered over the Texas panhandle produced deep upslope flow over the high plains and against the Front Range mountains. The storm produced blizzard conditions over the plains mainly south of Interstate 76. Interstate 70 as well as other roads and highways was closed from Denver to the Kansas line due to snow and blizzard conditions. Greyhound was forced to cancel all bus trips from Denver. The heaviest snow fell in and near the foothills and south of Denver over the palmer divide…where north winds sustained at speeds of 20 to 30 mph with gusts to 40 mph piled the snow into drifts 4 to 14 feet deep. In the city…the heavy snowfall persisted for a total of 29 hours. Snowfall totals across metro Denver included: 17.5 inches at Ken Caryl; 15 inches 3 miles south-southeast of Morrison; 14 inches in Boulder and lone tree; 12 inches in Castle Rock and Highlands Ranch; 11 inches in Wheat Ridge; 10.5 inches in Littleton; 10 inches in Arvada…Broomfield…and Louviers; and 8.5 inches in Lakewood and Thornton. Officially…snowfall totaled 8.0 inches at Denver Stapleton. North winds sustained to 25 mph with gusts to 32 mph produced some blowing snow at Denver International Airport. In the city…this second storm increased the total snowfall for the month to 29.4 inches…making the month the third snowiest on record. In the foothills the snow fell at a rate of 3 to 4 inches an hour at times. Total snowfall in the foothills included: 30 inches near Genesee; 29.5 inches 12 miles northwest of Golden; 25 inches in Evergreen and near Bergen Park; 24 inches near Conifer; 23.5 inches 3 miles southwest of Golden and near Gold Hill; 23 inches near Jamestown; 22.5 inches in Rollinsville; 19.5 inches in Aspen Springs; 19 inches near Blackhawk; 18.5 inches at Nederland; 16 inches in Indian Hills…at Intercanyon…and in Eldora; 15.5 inches at Echo Lake; and 12 inches near Ralston Reservoir. The total cost of snow removal just at Denver International Airport from this storm and the previous storm was in tens of millions of dollars. The airport estimated up to 6.7 million dollars in extra costs for contractors…overtime…equipment…de-icing chemicals…and other expenses. The two storms cost the airport 4.6 million dollars in loss concession revenues. United Airlines reported lost revenue of over 25 million dollars from the two storms…while Frontier Airlines lost an estimated 12.1 million dollars.

29

In 1997…high winds persisted mainly in and near the foothills. Strong cross winds gusting between 60 and 70 mph blew a rental truck off the roadway in northern Jefferson County near the Coal Creek Canyon road. West winds gusted to 33 mph at Denver International Airport.

In 2005…high winds were recorded across metro Denver. Peak wind gusts included 75 mph near Chatfield Reservoir and 64 mph at Denver International Airport. No damage was reported.

29-30

In 1898…heavy snowfall totaled 6.2 inches in downtown Denver. Northeast winds were sustained to 35 mph with gusts to 40 mph on the 29th.

In 1912…strong winds buffeted Boulder…causing hundreds of dollars damage. The winds were described as one of the most terrific in the history of the city.

In 1923…a cold wave caused temperatures to plunge 58 degrees in 24 hours. The temperature was 54 degrees at 2:00 pm on the 29th and only 4 degrees below zero at the same time on the 30th. The low temperature of 14 degrees on the 29th was the high temperature on the 30th. The low temperature on the 30th dipped to 10 degrees below zero. Light snowfall totaled only 0.7 inch. Northeast winds were sustained to 23 mph on the 29th.

In 2008…very strong Chinook winds blasted areas in and near the foothills of Boulder and Jefferson counties. The wind blew down trees and power poles…downed electrical lines and fences…and damaged homes and vehicles. Scattered power outages were reported along the Front Range. In metropolitan Denver alone…24000 Xcel customers were affected by the outages. Four planed were damaged at the Vance Brand Municipal Airport in Longmont…one was heavily damaged. Insurance companies estimated up to 7 million dollars in damage. Peak wind gusts included 87 mph at the national wind technology center…86 mph…2 miles north of Longmont; 77 mph at Erie…and 75 mph at Lafayette. On the 30th…a peak wind gust to 47 mph was recorded at Denver International Airport. .

30

In 1875…snow fell from the early morning into the early evening. While the amount of snowfall was not recorded… Precipitation from melted snow totaled 0.53 inch. Good sleighing was reported…so snowfall must have been 5 inches or more.

In 1895…northwest winds were sustained to 60 mph in the city.

In 1897…west winds sustained to 52 mph with gusts to 60 mph warmed the temperature to a high of 55 degrees.

In 1912…west winds were sustained to 48 mph with gusts to 52 mph. The Chinook winds warmed the temperature to a high of 50 degrees.

In 1928…snowfall was 0.1 inch in downtown Denver. This was the only measurable snow of the month…ranking the month the third least snowiest on record in the city.

In 1990…strong downslope winds buffeted the eastern foothills. Wind gusts to 91 mph were recorded atop Table Mesa in southwest Boulder…while a gust to 94 mph was clocked at Rollinsville. The high winds caused whiteout conditions due to blowing snow along some highways south and north of Boulder. The high winds downed power lines near the Rocky Flats plant south of Boulder.

In 1998…high winds continued to buffet areas in and near the foothills. Near Evergreen…a 100-foot-high blue spruce crashed down on the roof of a home…splitting the corrugated metal roof in half. Fortunately…the tree… Which measured 10 feet in circumference…only penetrated the home’s interior in a few places. Peak wind reports included: 90 mph at Wondervu…88 mph at the Rocky Flats test facility…83 mph near Conifer…and 82 mph atop Blue Mountain near Coal Creek Canyon. West winds gusted to 39 mph at Denver International Airport.

30-31

In 1886…heavy snow totaled 6.5 inches in downtown Denver. Most of the snow…4.5 inches…fell on the 31st. North winds were sustained to 18 mph.

In 1928…snowfall of 0.6 inch was the only measurable snow of the month in the city.

In 1947…post-frontal heavy snow totaled 6.3 inches over downtown Denver. Most of the snow fell on the 30th. North winds were sustained to 17 mph on the 30th.

In 1995…the foothills west of Denver received 5 to 9 inches of new snow…except for Bailey where 11 inches of snow were measured. No snow fell at the site of the former Stapleton International Airport.

31 Continue reading December 29 to January 4: This Week in Denver Weather History

December 22 to December 28: This Week in Denver Weather History

This Week in Denver Weather History

The period around the Christmas holiday has historically been a pretty eventful one for the Denver metro area. Our look back at this week in Denver weather history showcases a wide variety of extreme conditions. From powerful, damaging winds to extreme cold to monstrous blizzards, we can and have seen it all.

From the National Weather Service:

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.

18-24

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.

19-23

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.

20-22

In 1933…strong downslope winds produced a warm spell. Low temperatures of 43 degrees on both the 20th and 21st and 41 degrees on the 22nd were record high minimums for those dates. High temperature of 67 degrees on the 21st was a record maximum for the date. High temperatures of 56 degrees on the 20th and 69 degrees on the 22nd were not records; however…the 69 degrees was the warmest of the month. West to northwest winds were sustained to 20 and 24 mph on the 21st and 22nd respectively.

20-23

In 1918…light snowfall on each day totaled 12.0 inches over downtown Denver. Northeast winds were sustained to 16 mph on the 21st.

20-25

In 1983…an extremely bitter cold spell occurred. The temperature remained below zero for 115 hours in Denver… The longest sub-zero period on record. The mercury dipped to 21 degrees below zero on the 21st…the coldest recorded temperature in over 20 years. The cold was accompanied by winds that plunged chill factors to 50 to 70 degrees below zero. Two people froze to death in Denver; both were found outside dead of exposure. Numerous cases of frostbite were reported. Hundreds of water pipes broke from the intense cold…water mains and natural gas lines also fractured…and electricity consumption reached record levels. Light snow totaling 5.8 inches fell at times…and holiday traffic was delayed at Stapleton International Airport for several hours. Eight daily temperature records were set at the time. The all-time record low maximum temperature for the month of 8 degrees below zero on the 21st still stands today. Other temperature records still standing include record low maximum temperatures of 5 degrees below zero on both the 22nd and 23rd and 4 degrees below zero on the 24th.

21-22

In 1969…strong winds raked the eastern foothills in Boulder and Jefferson counties. Wind gusts to 115 mph were recorded at the National Center for Atmospheric Research in Boulder…while in downtown Boulder winds gusted to 75 mph. Some damage occurred.

In 1981…a snow storm dumped 3 to 8 inches of snow across eastern Colorado. Snowfall totaled 6.8 inches at Stapleton International Airport where north winds gusted to only 17 mph.

In 2011…large scale lift from an upper level low combined with a deep easterly upslope flow behind a cold front to produce heavy snow in and near the Front Range foothills and Palmer Divide. Storm totals ranged from 1.5 to 3 feet in the Front Range foothills…with 1 to 1.5 feet along the urban corridor. In the Front Range foothills and Palmer Divide…storm totals included: 36.5 inches…7 miles southwest of Boulder; 32 inches…12 miles northwest of Golden; 28 inches at Genesee; 24.5 inches…3 miles west of Jamestown; 23 inches at Bergen Park; 21 inches at Evergreen and Gross Reservoir; 19 inches near Eldorado Springs and 3 miles west-southwest of Conifer; 17 inches…4 miles south- southwest of Tiny Town; and 13.5 inches…15 miles north of Elizabeth. Along the urban corridor…storm totals included: 18 inches in Golden; 14.5 inches in Boulder…13 inches at the National Weather Service in Boulder; 12.5 inches…5 miles south-southwest of Arapahoe Park; 12 inches at Lone Tree; 11.5 inches in Broomfield; 11 inches in Arvada…4 miles northwest of Elbert…Niwot and Wheatridge; 10 inches in northwest Denver; with 7.3 inches at Denver International Airport.

21-23

In 1924…heavy snowfall totaled 7.9 inches over downtown Denver. During the storm north to northeast winds were sustained to 21 mph. Temperatures were quite cold…ranging from a high of 24 degrees on the 21st to a low of 5 degrees below zero on the 23rd.

In 1964…high winds were recorded along the eastern foothills. A wind gust to 100 mph was registered at Jefferson County Airport near Broomfield. In Boulder… Where many thousands of dollars in damage occurred…warm Chinook winds gusted in excess of 45 mph downtown. A wind gust to 82 mph was recorded at the National Center for Atmospheric Research in Boulder. Heavy damage to power lines…homes…and roads was reported at Evergreen…Golden… And Boulder. Several people were injured by wind-caused accidents. West winds gusted to 53 mph on the 22nd and to 51 mph on the 23rd at Stapleton International Airport where some blowing dust occurred. The Chinook winds warmed temperatures in Denver to highs of 68 degrees on the 22nd and 71 degrees on the 23rd.

Continue reading December 22 to December 28: This Week in Denver Weather History

December 15 to December 21: This Week in Denver Weather History

This Week in Denver Weather History

Powerful, damaging wind, deadly cold and monster snowstorms are the highlights of this week in Denver weather history.

From the National Weather Service:

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.

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.

Continue reading December 15 to December 21: This Week in Denver Weather History

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