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 →

Wind and snow are two hallmarks of Denver’s November weather and we see an abundance of those events in our look back at this week in Denver weather history. Damaging wind makes numerous appearances as does wintry weather.

From the National Weather Service:

11-14

In 1970…heavy snowfall totaled 7.2 inches at Stapleton International Airport where northeast winds gusted to 22 mph on the 12th and 14th. Most of the snow… 4.2 inches…fell on the 12th.

12-13

In 1961…heavy snowfall totaled 5.6 inches at Stapleton Airport. East-northeast winds gusted to only 20 mph.

12-15

In 1909…light snowfall totaled 6.7 inches in downtown Denver over the 4 days. This was the first measurable snowfall of the season. Northeast winds were sustained to 15 mph on the 12th.

13

In 1951…northwest wind gusts to 50 mph were recorded at Stapleton Airport.

In 1983…winds gusted to around 60 mph in and near the foothills. There were scattered power outages and a few broken windows across metro Denver. The strong winds did 10 thousand dollars in damage to awnings at the Brown Palace Hotel in downtown Denver. West winds gusted to 46 mph at Stapleton International Airport.

13-14

In 1925…heavy post-frontal snowfall totaled 6.4 inches overnight in downtown Denver. Northwest winds were sustained to 27 mph with gusts to 29 mph on the 13th.

In 1974…northwest winds gusted to 52 mph at Stapleton International Airport…warming the temperature to 60 degrees shortly after midnight on the 13th. A cold front cooled temperatures into the 20’s by late morning and produced snowfall of 3.7 inches. The low temperature dipped to 14 degrees on the 14th.

In 1993…an upper level low pressure system combined with a weak but moist upslope flow to produce heavy snow across metro Denver. Snowfall amounts averaged 6 to 8 inches with up to 16 inches in the foothills at the Eldora Ski Area. Snowfall totaled 6.0 inches at Stapleton International Airport where north winds gusted to only 20 mph on the 14th. Most of the snow fell on the 14th.

In 1994…heavy snow developed rapidly along the Front Range urban corridor with the heaviest snow over northwest metro Denver. Sixteen to 18 inches of snow fell in Boulder… Lafayette…and Louisville. This was the second heavy snowfall over northwest metro Denver in 10 days. Eleven to 14 inches of snow were measured from Longmont southward into Aurora. Snowfall totaled 12.1 inches at Stapleton International Airport where northeast winds gusted to 29 mph on the 13th. Most of the snow…9.0 inches…fell on the 14th.

In 1997…heavy snow fell overnight in portions of Jefferson and Boulder counties. About 5.5 inches of snow were reported in Boulder…while 4 inches were measured 12 miles southwest of Morrison and 6 miles southwest of Golden. Snowfall totaled only 1.8 inches at the site of the former Stapleton International Airport. Northeast winds gusted to 26 mph at Denver International Airport.

14

In 1874…west winds blew at gale speeds from midnight until mid afternoon when the winds abated. The maximum sustained velocity was 48 mph.

In 1928…strong winds caused 3 hundred to 5 hundred dollars damage in Boulder. Wind gusts to 70 mph were recorded at Valmont just east of Boulder.

In 2006…an upper level jet stream combined with a high surface pressure gradient behind a cold front to produce strong winds across metro Denver. A wind gust to 66 mph was recorded in Longmont. North winds were sustained to 38 mph with gusts to 52 mph at Denver International Airport where winds were strong and gusty most of the day.

Continue reading November 13 to November 19 – This Week in Denver Weather History →

Our look back at this week in Denver weather history is dominated with two types of events: snow and wind. November is our second snowiest month and we see many significant snowfall events in the past. Wind is a fact of life on the plains and in Denver and damaging events have occurred with relatively frequency as we can see below.

From the National Weather Service:

5-6

In 1938…heavy snowfall totaled 7.5 inches over downtown Denver. North winds were sustained to 16 mph with gusts to 19 mph on the 5th.

5-7

In 1918…rain was mixed with and changed to snow…which became heavy and totaled 8.1 inches in downtown Denver. North winds were sustained to 21 mph with gusts to 23 mph.

6

In 1962…west winds gusted to 55 mph…briefly reducing the visibility to 1 1/2 miles in blowing dust at Stapleton Airport. The strong winds blew all day.

In 1989…high winds to 62 mph were recorded in Boulder. Northwest winds gusted to 33 mph at Stapleton International Airport.

In 1991…strong westerly Chinook winds blew into metro Denver with gusts to 88 mph recorded at Rollinsville and to 51 mph in Boulder. Later…northeast winds with gusts of 30 to 40 mph were common across all of metro Denver behind a cold front…which produced only 0.2 inch of snowfall at Stapleton International Airport.

7

In 1958…a strong cold front produced northeast wind gusts to 52 mph at Stapleton Airport where some blowing dust was observed.

In 1980…Chinook winds at sustained speeds of 40 mph were recorded with a peak gust to 71 mph measured at Wondervu southwest of Boulder. West winds gusted to 25 mph at Stapleton International Airport.

In 1989…strong winds buffeted many foothills areas. Wind gusts of 60 to 70 mph were recorded in Boulder and Longmont. Northwest winds gusted to 43 mph at Stapleton International Airport.

In 1996…wind gusts to 75 mph were recorded at Golden Gate Canyon and at the Rocky Flats Environmental Test Facility northwest of Denver. Northwest winds gusted to 40 mph at Denver International Airport.

In 1998…upslope conditions…coupled with a moist and unstable air mass…allowed heavy snow to develop in the foothills west of Denver. Snowfall generally ranged from 4 to 6 inches…but 7 inches were measured 4 miles south of Evergreen. Only 1.2 inches of snow fell at the site of the former Stapleton International Airport. This was the first measurable snow of the season.

7-8

In 1969…wind gusts to 48 mph in downtown Boulder caused minor damage.

8

In 1896…southwest Chinook winds sustained to 42 mph with gusts as high as 46 mph warmed the temperature to a high of 53 degrees.

In 1977 near-blizzard conditions in blowing snow caused the closure of I-70 to the west of Denver in clear creek canyon and east of Denver to Limon. Northeast wind gusts to 46 mph were recorded at Stapleton International Airport where snowfall totaled only 1.1 inches.

In 1984…a rare November thunderstorm produced west winds gusting to 31 mph…but only 0.04 inch of rain at Stapleton International Airport.

In 1996…high winds gusting from 80 to 100 mph were recorded at Wondervu in the foothills southwest of Boulder. West northwest winds gusted to 32 mph at Denver International Airport.

In 2006…the temperature in Denver climbed to a high of 80 degrees. This was the first time the temperature had ever exceeded the 70’s in November since records began in 1872. This new all-time record maximum temperature for the month of November was also a new daily record and the highest temperature ever recorded so late in the season.

Continue reading November 6 to November 12 – This Week in Denver Weather History →

The further we go into the cold season, the more we see significant winter-like events in our look back at Denver weather history. Many significant snowstorms have occurred this week in the past including one in 1946 that dumped more than 30 inches of snow on Denver.

From the National Weather Service:

28-30

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

28-31

In 1929…rain changed to snow on the afternoon of the 28th and continued until midday on the 30th followed by intermittent light snow which continued through the 31st. Snowfall over the four days totaled 16.2 inches in the city. Most of the snow…8.5 inches…fell on the 29th with 6.1 inches on the 30th. Temperatures hovered in 20’s during most of the storm.

29-30

In 1905…heavy snowfall developed on the evening of the 29th and continued through the evening of the 30th. Snowfall totaled 11.0 inches in downtown Denver. Precipitation was 1.02 inches. Temperatures were generally in the 20’s.

In 1959…rain during most of the day on the 28th changed to snow early on the 29th and continued through most of the 30th. Heavy snowfall totaled 7.4 inches at Stapleton Airport. North-northeast winds gusted to 24 mph on the 30th. Some freezing drizzle also occurred on the 30th.

In 1981…4 to 8 inches of new snow were recorded in the foothills west of Denver. Snowfall totaled only 0.4 inch at Stapleton International Airport where north winds gusted to 25 mph.

29-31

In 1889…the first snowfall of the season totaled 14.0 inches over the three days in downtown Denver. Snowfall was 8.0 inches on the 29th and 5.0 inches on the 31st. North to northeast winds gusted to 30 mph on the 29th.

In 1950…a warm spell resulted in five daily temperature records. Record highs of 84…80…and 79 degrees occurred on the 29th…30th…and 31st…respectively. Low temperature of 49 degrees on the 30th was the record high minimum for the date.

In 1991…the second surge of cold arctic air in a matter of days plunged metro Denver into the deep freeze. While low temperatures remained above zero…high temperatures were only in the 20’s. Three temperature records were set: record lows of 7 degrees on the 30th and 10 degrees on the 31st and a record low maximum of only 21 degrees on the 30th. Snowfall was light with only 1.9 inches recorded at Stapleton International Airport where east winds gusted to 23 mph.

In 2002…snowfall totaled 4.3 inches at the site of the former Stapleton International Airport. North winds gusted to 32 mph on the 29th behind a cold front…which plunged temperatures well below seasonal normals. High temperatures of 18 degrees on the 30th and 19 degrees on the 31st were record low maximums for each date. Low temperatures dipped to 12 degrees on the 30th and 15 degrees on the 31st.

29-1

In 1972…heavy snowfall totaled 15.5 inches at Stapleton International Airport. However…the heaviest snow occurred on Halloween night when 7 inches fell on trick-or-treaters during a short 3-hour period. I-25 was closed south of Denver. North winds gusting to 29 mph caused some blowing snow on the 1st. The snow started late on the 29th and ended during the mid afternoon on the 1st. The greatest snow depth on the ground at Stapleton International Airport was 13 inches on the 1st.

30

In 1974…a rare thunderstorm for so late in October produced hail to 3/8 inch in diameter and 0.10 inch of rain at Stapleton International Airport.

In 1991…the high temperature warmed to only 21 degrees…the all-time record low maximum for the month of October. The same temperature also occurred on October 25…1997.

31

In 1997…high winds buffeted the foothills and adjacent areas of metro Denver. West winds gusted to 70 mph in Broomfield and to 40 mph at Denver International Airport. The strongest winds occurred in the mountains west of Denver and in the foothills north of Denver.

In 2001…high winds developed in the foothills. Peak wind gusts were measured to 74 mph at the National Center for Atmospheric Research on the mesa in Boulder and to 72 mph near Rollinsville. West winds gusting as high as 53 mph warmed the temperature to a high of 71 degrees at Denver International Airport.

31-1

In 1951…6.4 inches of snowfall were measured at Stapleton Airport.

In 1989…a Halloween storm dropped 3 to 6 inches of snow on metro Denver with the adjacent foothills receiving 5 to 10 inches. Snowfall totaled 4.5 inches at Stapleton International Airport…where north winds gusted to 31 mph on the 31st. Most of the snow fell on the evening of the 31st…but the storm left icy streets throughout metro Denver on the morning of the 1st…making it a “spooky” commute for many motorists.

In 2004…heavy snow fell in and near the foothills of Jefferson and Douglas counties. Storm total snowfall included: 14.5 inches in aspen park…10 inches at Boxborough state park and and near Sedalia…8 inches near bergen park…and 7 inches in Highlands Ranch. Snowfall totaled only 3.2 inches in the Denver Stapleton area. Post-frontal northeast winds gusted to 41 mph at Denver International Airport.

Continue reading October 30 to November 5 – This Week in Denver Weather History →