Tag Archives: December Weather

December 21 to December 27: This Week in Denver Weather History

This Week In Denver Weather History
December 21 to December 27: This Week in Denver Weather History

Powerful, damaging winds and monstrous snowstorms are the big highlights of this week in Denver weather history. Two storms are more memorable than most including the pre-Christmas blizzard of 2006 and of course the infamous 1982 Christmas Eve blizzard.

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.

18-21

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.

19-23

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.

20-21

In 1969…high winds caused widespread…but mostly minor damage to roofs…windows…and power lines and overturned some house trailers in areas along and just east of the foothills. Wind gusts of 60 to 70 mph were reported in Boulder and south of Boulder at Rocky Flats. A wind gust to 115 mph was measured in Boulder at the National Center for Atmospheric Research. At Stapleton International Airport…west winds gusted to 44 mph on the 20th and to 45 mph on the 21st. The warm Chinook winds warmed the high temperature to 56 degrees on the 20th and to 65 degrees on the 21st.

In 2006…a major blizzard buried greater metro Denver and the adjacent foothills in deep snow. A slow moving upper level low pressure center produced deep moist upslope flow over the high plains and against the eastern slopes of the mountains…allowing heavy snowfall to persist for 34 hours across metro Denver. Total snow accumulations ranged from 1 to 2 1/2 feet across the city and from 2 to nearly 4 feet in the foothills. Adding to the misery… Strong north winds sustained at 20 to 35 mph with gusts from 45 to nearly 60 mph produced much blowing snow and piled the snow into drifts from 6 to 12 feet high…closing businesses and bringing all transportation to a halt. The storm forced the closure of Denver International Airport for a total of 45 hours which snarled the nation’s air traffic system. This was the longest closure in the airport’s 12 year history. The closure stranded nearly 5000 travelers when 2000 flights were canceled. Many inbound flights were diverted to other airports…stranding even more passengers. Many of the stranded travelers failed to reach their final destinations until days after the airport re-opened due to fully booked flights during the holiday season. Police and national guardsmen rescued hundreds of commuters stuck in their cars…and sent them to temporary shelters set up by the Red Cross. All interstates and other major highways in and out of Denver were closed. Greyhound was forced to cancel all bus trips from Denver. Mail delivery was suspended. The Regional Transportation District suspended all metro Denver bus service for the first time since the March 2003 blizzard. The roof of a discount store in Aurora collapsed under the weight of the heavy snow. In Lakewood…a power outage left 5600 residents without electricity for a brief time. Metro Denver snowfall amounts included: 34 inches 10 miles southeast of Buckley AFB…32 inches in Littleton…30 inches in Thornton and near Castle Rock…29.5 inches near Parker…28 inches in Wheat Ridge…25.5 inches at Centennial Airport…25 inches at Niwot…24 inches in Aurora…22.5 inches at Greenwood Village… 22 inches in Arvada…21.5 inches in Lakewood…20 inches in Longmont…and 15.5 inches in Boulder. Snowfall measured 20.7 inches officially in the Denver Stapleton area. This ranked the snowfall as the 7th greatest in the city since 1946. North winds were sustained to 37 mph with gusts to 55 mph at Denver International Airport. In the foothills snowfall totaled: 42 inches at Conifer and 11 miles southwest of Boulder…40 inches at Evergreen…39 inches at Aspen Springs… 37.5 inches 8 miles north of Blackhawk…33 inches near Nederland…31 inches at Intercanyon and near Tiny Town…30.5 inches atop buckhorn mountain…30 inches near Indian Hills… 29 inches at Rollinsville…24 inches near Gross Reservoir and Ralston Reservoir…22.4 inches atop Crow Hill…and 20 inches near Georgetown. Snowpacked and rutted streets and parking lots persisted for a month or more after the storm and subsequent storms. The heavy snowfall created a snow removal controversy when many citizens complained that residential streets were not cleared in a timely manner in the city and in some suburban areas. This was in spite of the fact that tens of millions of dollars were spent on snow removal. In the city of Denver…snow cover of an inch or more from this storm and subsequent storms persisted for 61 consecutive days…through February 19…2007. This is the second longest period of snow cover on record in the city. Many homeowners who had extensive Christmas lights and decorations in their yards were not able to remove the lights because the wires were buried in deep snow and ice until the end of February or later.

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.

Continue reading December 21 to December 27: This Week in Denver Weather History

December 14 to December 20: This Week in Denver Weather History

This Week In Denver Weather History
December 14 to December 20: This Week in Denver Weather History

Bitter cold, powerful winds and major snowstorms are the biggest highlights of this week in Denver weather history.

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.

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.

13-14

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.

Continue reading December 14 to December 20: This Week in Denver Weather History

December 7 to December 13: This Week in Denver Weather History

This Week In Denver Weather History
December 7 to December 13: This Week in Denver Weather History

Arctic cold, heavy snow and  powerful, damaging winds are the highlights in our look back at this week in Denver weather history.

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.

5-7

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.

6-7

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.

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.

Continue reading December 7 to December 13: This Week in Denver Weather History

Thornton’s December weather preview: Arrival of winter can bring highly variable conditions

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.

Through November, the snow season along the Colorado Front Range has been dismal.  With a mere 4.0 inches of snow having been recorded in Denver (3.0 in Thornton), seasonal snowfall is 9.0 inches below normal.

December can prove to be a rebound month and help bolster those numbers.  However precipitation can be hit or miss as while monster snowstorms are possible, we have also seen starkly dry years.

Current long range forecasts point to a warm start to the month followed by seasonal conditions.

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.

December 2013 weather recap: Record setting hot and cold, little snow

Thornton and the Denver area closed out 2013 with a display of typically highly variable weather.  We recorded some record low temperatures followed by unseasonably warm conditions.  One thing that was lacking was snow.

The first three days of the month started out quite mild with highs well above normal.  That changed quickly midday on the third as low pressure moved in bringing an extended Arctic blast.

For six straight days high temperatures remained stubbornly below freezing and lows dipped into the single digits.  The cold snap was notable but not record-setting in terms of length.  Two daily low temperature records were tied or broken however.

Warmer weather returned on the 10th as the mercury finally started to climb.  Unseasonably warm temperatures became the rule for the next nine days that included a record high temperature on the 18th.

The last third of the month was a bit more variable with its ups and downs but overall warmer than normal conditions.

Overall Thornton’s monthly average temperature came in at 29.2 degrees.  Out at Denver International Airport where the Mile High City’s official stats are recorded, it was a bit cooler with an average of 28.4 degrees.  Both were below Denver’s December average of 30.0 degrees.

Thornton recorded nine days with high temperatures that failed to reach 32 degrees.  On five days, low temperatures dropped below zero.  Denver saw eight days with highs below freezing, six with lows below zero.

The warmest temperature of the month in Thornton came on the 18th when we recorded 66.8 degrees. Our coldest was -9.3 degrees on the 5th.  Denver’s warmest day was on the 18th as well with a high of 68 degrees.  Its lowest temperature was -15 degrees on the 5th.

Four temperature records were tied or broken in Denver.

The low temperature of -13 degrees on December 4th shattered the old record low for the date of -5 degrees last set in 2008.  The following day, on December 5th, the low temperature of -15 degrees tied the record low last set in 1972.

The mild weather December 18 saw two records.  The high of 68 degrees broke the previous high temperature record for the date of 66 degrees last set in 1979.  Also, the day tied the record high minimum for the 18th of 40 degrees set in 1917.

Precipitation for the month of December 2013 was not as noteworthy as the temperatures.  Thornton recorded only 0.24 inches in our bucket while Denver received 0.25 inches.  Both were a good bit below the December average of 0.35 inches.

Snow was similarly less than extraordinary.  Thornton measured 5.7 inches of the white stuff while Denver lagged that with 4.7 inches.  Both totals were below the normal for December of 8.5 inches.  Seasonal snowfall totals at this point are about half of what they normally are.

Click here to view Thornton’s December 2013 climate summary.

Thornton's December 2013 Temperatures.
Thornton’s December 2013 Temperatures.
Thornton's December 2013 Precipitation.
Thornton’s December 2013 Precipitation.
CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO
200 AM MST WED JAN 1 2014

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

...THE DENVER CO CLIMATE SUMMARY FOR THE YEAR OF 2013...

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2013

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH             105   06/26/2012
                        06/25/2012
                        07/20/2005
 LOW              -29   01/09/1875
HIGHEST           100   07/11        64      36      105  06/26
                        06/11                             06/25
LOWEST            -15   12/05        36     -51       -6  01/11
AVG. MAXIMUM     63.9              64.7    -0.8     68.4
AVG. MINIMUM     36.3              36.3     0.0     39.3
MEAN             50.1              50.5    -0.4     53.9
DAYS MAX >= 90     54              39.6    14.4       73
DAYS MAX <= 32     29              20.0     9.0       19
DAYS MIN <= 32    169             156.9    12.1      132
DAYS MIN <= 0      11               5.8     5.2        4 
PRECIPITATION (INCHES) 
RECORD 
 MAXIMUM        23.31   1196 
 MINIMUM         7.29   2008 
TOTALS          17.60             14.30    3.30    10.11 
DAILY AVG.       0.05              0.04    0.01     0.03 
DAYS >= .01        82              79.7     2.3       52
DAYS >= .10        42              34.9     7.1       23
DAYS >= .50         8               7.6     0.4        9
DAYS >= 1.00        3               2.3     0.7        1
GREATEST
 24 HR. TOTAL    2.39   MM                       12/31 TO 12/31
                                                          12/31 TO 12/31
                                                          12/31 TO 12/31
 STORM TOTAL       MM                                 MM
 (MM/DD(HH))            MM                    12/31(00) TO 12/31(00)
                                                 12/31(00) TO 12/31(00)1
                                                 12/31(00) TO 12/31(00)1

SNOWFALL (INCHES)
RECORDS
 TOTAL             MM   5
 24 HR TOTAL       MM
 SNOW DEPTH        MM   MM
TOTALS           74.1              53.8    20.3     38.5
 LIQUID EQUIV    7.41              5.40    2.01     3.85
SINCE 7/1         8.1              22.5   -14.4     12.4
 LIQUID 7/1      0.81              2.20   -1.39     1.24
SNOWDEPTH AVG.      0                MM      MM        0
DAYS >= TRACE      60              33.3    26.7       36
DAYS >= 1.0        20              16.3     3.7       13
GREATEST
 SNOW DEPTH         9   02/25                         11  02/04
 24 HR TOTAL      9.1   MM                       12/31 TO 12/31
                                                          12/31 TO 12/31
                                                          12/31 TO 12/31
 STORM TOTAL       MM                                 MM
 (MM/DD(HH))            MM                    12/31(00) TO 12/31(00)
                                                 12/31(00) TO 12/31(00)1
                                                 12/31(00) TO 12/31(00)1

DEGREE_DAYS
HEATING TOTAL    6302              6059     243     5198
 SINCE 7/1         MM              2468      MM       MM
COOLING TOTAL     999                 0     999     1236
 SINCE 1/1        999               769     230     1236

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

WIND (MPH)
AVERAGE WIND SPEED              9.7
RESULTANT WIND SPEED/DIRECTION   2/201
HIGHEST WIND SPEED/DIRECTION    64/060    DATE  06/18
HIGHEST GUST SPEED/DIRECTION    97/040    DATE  06/18

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.60
NUMBER OF DAYS FAIR           69
NUMBER OF DAYS PC            232
NUMBER OF DAYS CLOUDY         64

AVERAGE RH (PERCENT)     52

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN               14     RAIN                      25
LIGHT RAIN               80     FREEZING RAIN              0
LT FREEZING RAIN          4     HAIL                       0
HEAVY SNOW               11     SNOW                      23
LIGHT SNOW               58     SLEET                      0
FOG                     105     FOG W/VIS <= 1/4 MILE     33
HAZE                     88

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

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

This Week In Denver Weather History
December 29 to January 4: 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.

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
December 22 to December 28: 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.

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
December 15 to December 21: 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.

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

Thornton’s sub-freezing cold streak notable but not particularly unusual

Thornton, Colorado temperatures during the December 2013 cold spell.
Thornton, Colorado temperatures during the December 2013 cold spell.

Thornton’s December 2013 Arctic blast has come to an end as the mercury finally climbed above freezing today.  For nearly seven straight days we saw temperatures below 32 degrees.

Soon after noon on Tuesday, December 3 the cold front arrived along the Colorado Front Range.  The mercury would plummet quickly from a high that day of 55.9 degrees and drop below freezing at 1:56 p.m.

It wasn’t until 9:12 a.m. this morning when the temperature finally climbed above 32 degrees, the rising temperatures being pushed higher by Chinook winds.  In all, sub-freezing temperatures were recorded for 6 days, 19 hours and 16 minutes straight.

Looking at how the event ranks in comparison to historical Denver cold spells, it falls short of making the list of top 10 longest periods with maximum temperatures below freezing.

Number 10 on the list is a nine day streak that ended on December 25, 1983.  The top spot goes to a 14 day period that ended on November 29, 1880.

During the recent cold spell Denver recorded two low temperature records.

Snowfall was relatively minimal however as is often the case when temperatures drop so far.  Thornton measured 2.4 inches and Denver 3.1 inches.

The table below shows the high and low temperatures for Thornton and Denver during the cold spell.

Date Thornton High Thornton Low Denver High Denver Low
12/3/13 55.9 11.4 56 11
12/4/13 12.3 -4.3 11 -13 *
12/5/13 12.2 -9.3 8 -15 *
12/6/13 12.3 -6.8 8 -13
12/7/13 13.9 -6.6 9 -11
12/8/13 20.9 1.8 17 -5
12/9/13 30.5 -3.8 25 -4
12/10/13 46.9 13.2

* Record low temperatures

Denver, Colorado sub-freezing temperature streaks.  (National Weather Service)
Denver, Colorado sub-freezing temperature streaks. (National Weather Service)

 

The minimum temperature at Denver International Airport dropped below zero for six consecutive days from December 4th through December 9th 2013. The longest consecutive stretch of below zero low temperatures occurred back in December of 1972. (National Weather Service)
The minimum temperature at Denver International Airport dropped below zero for six consecutive days from December 4th through December 9th 2013. The longest consecutive stretch of below zero low temperatures occurred back in December of 1972. Click for a larger view. (National Weather Service)

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

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

As Denver tries to dig out from its most recent blast of bitter cold, our look back at this week in Denver weather history shows that the event is not particularly unusual. In addition to extreme cold, we have seen significant snowfall and damaging wind.

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.

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