Christmas Day is normally a relatively quiet day in terms of the weather as we recently discussed but the week between it and New Year’s can be quite eventful. Among the highlights are a prolonged period of sub-zero temperatures that lasted nearly five days. Just five years ago a blizzard struck the region that snarled holiday travel on the air and the ground.

From the National Weather Service:

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.

24-25

In 1891…heavy snowfall of 7.0 inches in downtown Denver provided a white Christmas. Most of the snow…6.5 inches… Fell on the 24th. Northwest winds were sustained to 30 mph with gusts to 40 mph on the 24th.

In 1894…snow began falling during the evening of the 24th… Ended during the early afternoon of the 25th…and totaled 6.4 inches in downtown Denver. Northwest winds were sustained to 26 mph with gusts to 30 mph on the 24th. The maximum snow depth on the ground was 5 inches. The high temperature was only 18 degrees on the 25th after a low of 8 degrees.

In 1980…strong Chinook winds of 50 to 60 mph occurred in the foothills with a wind gust to 90 mph recorded at Wondervu. West winds gusted to 33 mph at Stapleton International Airport on the 25th.

In 1997…a relatively rare Christmas snowstorm blanketed much of northeastern Colorado. Snowfall in and near the Front Range foothills and south of metro Denver ranged from 5 to 8 inches. Elsewhere…new snow accumulations were generally 1 to 3 inches. Snowfall totaled only 1.5 inches at the site of the former Stapleton International Airport. North winds gusted to 29 mph at Denver International Airport on the 24th.

25

In 1873…northwest winds were sustained to 36 mph during the morning and to 48 mph in the evening. The Chinook winds warmed the temperature to a high of 53 degrees.

In 1883…gusty very strong winds raked Boulder…causing 11 hundred dollars in damage.

In 1985…Table Mesa in Boulder was buffeted by wind gusts to 68 mph.

In 1993…occasional high winds occurred over portions of the higher foothills west of Boulder and Denver. A wind gust to 87 mph was recorded on squaw mountain…and a gust to 83 mph occurred at Rollinsville. Northwest winds gusted to 35 mph at Stapleton International Airport.

In 2007…a winter storm brought heavy snow to the Front Range of Colorado. The heaviest snow fell near the foothills of Boulder…Douglas and Jefferson counties. The snow caused accidents throughout the Denver metropolitan area. Gusty winds produced snow drifts from 2 to 3.5 feet in depth. Total snowfall for the calendar day in Denver was 7.8 inches…setting a new record for Christmas Day. The measurement was taken at the former Stapleton International Airport; the previous record was 6.2 inches… Set in 1894. Storm totals in the Front Range foothills included: 13.5 inches at Coal Creek Canyon; 12 inches…5 miles east-southeast of Aspen Park; 11 inches; 6 miles southwest of kassler; 10.5 inches at Eldorado Springs. Elsewhere…storm totals ranged from 5 to 10 inches. In the urban corridor storm totals included: 9 inches near Elizabeth; 8 inches in southwest Denver…Highlands Ranch…Marston Reservoir and Wheat Ridge; 7.5 inches in Arvada; 7 inches in Centennial and Lakewood; 6.5 inches in Aurora and 8 miles southeast of Watkins; 6 inches in Boulder…Englewood and Parker. Elsewhere…storm totals ranged from 3 to 5 inches.

25-26

In 1904…after a warm Christmas Fay with a high temperature of 50 degrees…a late day cold front plunged temperatures to a low of 7 degrees…produced northeast winds sustained to 40 mph with gusts to 54 mph…and produced 5.2 inches of snow overnight for a late white Christmas. The maximum temperature on the 26th was only 16 degrees.
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.

Continue reading December 25 to December 31 – This Week in Denver Weather History →

Looking back at Denver weather history, it is readily apparent that the week leading up to Christmas has historically been a very eventful one. There are certainly many of the snow and wind events we would expect to see. Most notable however are the major winter storms like the pre-Christmas storm of 2006 and of course what is arguably Denver’s most famous winter storm, the Christmas Eve Blizzard of 1982.

• For more on the Christmas Eve Blizzard of 1982, read our complete recap with photos here.

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

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.

18-21

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 18 to December 24 – This Week in Denver Weather History →

This time of year snow is a common occurrence but in our look back at this week in Denver weather history we are struck by the lack of significant snow events in the history books for the period. What we do see instead are a number of high wind events, many of which caused widespread damage.

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.

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.

9-13

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.

10-11

In 1933…downslope winds produced warm temperatures…resulting in record high minimums of 46 degrees on the 10th and 44 degrees on the 11th. High temperatures of 66 degrees on the 10th and 62 degrees on the 11th were not records. Southwest winds were sustained to 16 mph on the 10th.

In 1939…high temperatures of 70 degrees on the 10th and 74 degrees on the 11th were record maximums for the dates. The low temperatures of 39 degrees on the 10th and 41 degrees on the 11th were not records.

In 1948…high winds in Boulder and Louisville caused 1750 dollars in damage. Wind gusts in excess of 70 mph were reported at Valmont and Boulder airport. Chinook wind gusts to 60 mph briefly reduced the visibility to 1/4 mile in blowing dust at Stapleton Airport.

In 1989…the season’s greatest snowfall to date hit metro Denver with 6 to 12 inches of snow. Flight delays at Stapleton International Airport reached 2 hours. Multiple wrecks snarled traffic on I-25 both north and south of the city. Snowfall totaled 7.0 inches at Stapleton International Airport where north winds gusted to 25 mph on the 10th.

Continue reading December 11 to December 17 – This Week in Denver Weather History →

As we have seen in recent days, Old Man Winter oftentimes makes his appearance in earnest during the month of Denver. Looking back at this week in Denver weather history we can see that is not at all unusual.

From the National Weather Service:

1-5

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

2-4

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

2-17

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

3-4

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

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

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

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

Continue reading December 4 to December 10 – This Week in Denver Weather History →

Cold, snow and wind are the dominant conditions we see in our look back at this week in Denver weather history. All three are common this time of year and extremes with those conditions seem to be unusually common as well.

Among the highlights are numerous high wind events that not only caused damage but also injury to unprepared residents. Significant snowfall also appears many times including a storm in 1983 that shut down the city for the Thanksgiving weekend and left snow on the ground for 63 days.

From the National Weather Service:

25-27

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

25-28

In 1952…the average coldest 4-day period in November in the previous 81 years of record occurred. Maximum temperatures of 19…15…21…and 25 degrees were recorded. Minimum temperatures were below zero each day with readings of 7 below…6 below…5 below…and 6 below.

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.

26-27

In 1876…heavy snowfall totaled 9.0 inches over the city from 5:00 pm on the 26th through 5:00 p.m. on the 27th. Precipitation was 0.30 inch on the 25th and 0.60 inch on the 27th.

In 1919…an incursion of cold arctic air produced snowfall of 4.6 inches over downtown Denver. Temperatures dipped to 5 degrees below zero on the evening of the 26th and recovered to a high of only 1 degree below zero on the 27th…the all-time record low maximum for the month of November and the record for the date. Northwest winds were sustained to 25 mph with gusts to 26 mph on the 26th.

In 1923…snowfall of 2.0 inches was the only snow of the month. North winds were sustained to 22 mph on the 26th.

In 1972…heavy snowfall totaled 7.5 inches at Stapleton International Airport where north winds gusted to only 18 mph on the 27th.

In 1983…a Thanksgiving blizzard dumped 21.5 inches of snowfall in 37 hours with a maximum of 18 inches on the ground at Stapleton International Airport. The storm produced howling winds…which paralyzed Thanksgiving weekend transportation across all of eastern Colorado. On the 27th…Stapleton International Airport closed… Opening 24 hours later. Interstate highways were closed in all directions…but west…from Denver. At Stapleton International Airport…north winds gusted to 36 mph on the 26th and to 29 mph on the 27th. However…most wind speeds across metro Denver were 15 to 30 mph. Temperatures hovered in the teens and lower 20’s. Many stores and businesses closed. Several high school football games were postponed. Across metro Denver…snow depth varied from 15 inches in Commerce City to 28 inches near Chatfield Reservoir. Snow removal in Denver was estimated at 1.5 million dollars. Following the storm… An inch or more of snow remained on the ground for 63 consecutive days through January 27…1984. This is the longest period of continuous snow cover ever recorded in Denver.

In 1990…an early winter storm deposited 2 to 8 inches of wet snow across metro Denver. Snowfall totaled 3.4 inches at Stapleton International Airport where northeast winds gusted to 30 mph on the 26th.

In 1993…strong winds swept off the foothills across metro Denver. Sustained winds of 30 to 50 mph were common across the area. Wind gusts to 67 mph were recorded atop Squaw Mountain near Idaho Springs. West winds gusted to 36 mph at Stapleton International Airport on the 26th. The strong winds produced some blowing snow…reducing the visibility to less than one mile at times.

In 1995…snowfall totaled 3.7 inches at the former Stapleton International Airport site. The foothills west of Denver received 4 to 7 inches of snow. North-northeast winds gusted to 34 mph at Denver International Airport on the 26th.

Continue reading November 27 to December 3 – This Week in Denver Weather History →

With the Thanksgiving holiday approaching, travelers cast a wary eye on Denver’s weather and in our look back at this week in Denver weather history we see they have had cause for concern in the past. Snowstorms and wind have caused their share of problems. Also notable, it was 140 years ago that Denver’s first official weather observation occurred.

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From the National Weather Service:

18-20

In 1930…a major storm dumped a total of 13.6 inches of snowfall over downtown Denver. Most of the snow…9.4 inches…fell on the 19th when north winds were sustained to 23 mph. This was the only measurable snow of the month. Temperatures hovered in the 20’s and lower 30’s.

In 1956…an intense winter storm dumped 12.8 inches of snowfall on metro Denver. Strong north-northeast winds gusting to 33 mph at Stapleton Airport frequently reduced the visibility to 1/2 mile in snow and blowing snow on the 19th. Most of the snowfall…10.7 inches…occurred on the 19th.

19-21

In 1979…a heavy snowstorm buried most of Colorado under at least a foot of snow. Snowfall at Stapleton International Airport totaled 17.7 inches…the greatest snow depth since 1946. Winds to 60 mph produced 5-foot drifts paralyzing the city as temperatures hovered in the 20’s. While small airports closed…Stapleton remained open…but with long delays that snarled thanksgiving holiday traffic. Schools and businesses closed and postal deliveries were delayed. Almost all major highways leading out of Denver were closed to traffic for periods of time on the 20th and 21st. Most of the snow…13.5 inches…fell on the 20th. At Stapleton International Airport…north winds gusted to 35 mph on the 20th and to 38 mph on the 21st.

20

In 1871…the first official weather observation in Denver… Was taken by Henry Fenton…observer sergeant of the united states army signal service at 5:43 am. The office was located on the 2nd floor of a building at the corner of Larimer and g streets…now 16th street. The daily weather journal hand written entry for the day follows: “Snow fell heavily during past night. At 5:43 am it was snowing light and continued until 8 am. Wind during snow storm gentle and a little west of south…and continued there during the remainder of the day. Sky clear after 8 am. Very cold weather prevailed all day and night. Thermometer at 9:43 pm 14 degrees. Rain gauge and self-registering thermometer not in position owing to severe storm last week. Barometer falling during the morning and rising rapidly at night.”

In 1894…northwest Chinook winds sustained to 40 mph with gusts to 45 mph warmed the temperature to a high of 58 degrees in the city.

In 1909…steady and very strong winds in Boulder caused 3 thousand dollars in damage.

In 1915…post-frontal northeast winds sustained to 40 mph with gusts as high as 42 mph produced only a trace of snow. It was windy most of the day.

In 1923…west winds were sustained to 42 mph with gusts to 44 mph before daybreak. The strong winds persisted in the city for only about 3 hours.

In 1993…a wind gust to 72 mph was recorded at Table Mesa in southwest Boulder.

In 1994…winds gusted to 77 mph atop Squaw Mountain west of Denver. West winds gusted to 40 mph at Stapleton International Airport.

20-21

In 1898…snowfall totaled 4.0 inches in downtown Denver. Northeast winds were sustained to 48 mph with gusts as high as 60 mph behind an apparent cold front on the 20th… When temperatures plunged from a high of 66 degrees to a low of 9 degrees. On the 21st the high was only 24 degrees and the low was 2 degrees.

In 1970…a wind gust to 94 mph was recorded at gold hill in the foothills west of Boulder. Strong winds also swept across metro Denver. Wind gusts reached 59 mph in downtown Boulder…while at Stapleton International Airport west- northwest winds gusted to 43 mph on the 21st. Damage was minor.

In 1992…a large Canadian air mass moved into the state at the same time an upper level storm system approached from the west. The combination of cold air at the surface and very moist air aloft produced heavy snow across the entire state. Snowfall totaled 6.3 inches at Stapleton International Airport…where north winds gusted to 23 mph on the 20th. Snow was heavier in the foothills…with 14 inches at Wondervu…13 inches at Aspen Springs…Conifer… Boulder…and Gross Reservoir…8 inches at Rollinsville… And 10 inches at Golden Gate Canyon and Morrison.

In 2007…a storm system brought moderate to heavy snowfall to portions of the urban corridor. Storm totals included: 7 inches…3 miles south-southeast of Fort Collins…with 6 inches in Boulder and at Horsetooth Inlet Bay. Elsewhere… Storm totals ranged from 2 to 5 inches. Snowfall totaled 2.0 inches at the site of the former Stapleton International Airport.

Continue reading November 20 to November 26 – This Week in Denver Weather History →