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November 12 to November 18: This week in Denver weather history

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:

10-14

In 2014…an Arctic cold front on the 10th…associated with a strong storm system over the northern Rockies blasted into northeast Colorado. The temperature in Denver plummeted from the high of 64 degrees at 4:37 pm to 34 degrees by 5:53 pm. The temperatures continued to fall and dropped into the teens by early evening. The Arctic airmass remained entrenched over the region through the morning of the 14th…with the high temperatures failing to reach the teens from the 11th through the 13th. This was the first time since records have been taken in Denver…dating back to 1872…that there were three consecutive days with the maximum temperatures remained below 20 degrees in the month of November. In addition to the frigid temperatures…0.1 inch of snowfall was observed on 11th at Denver International Airport…which marked the first measureable snowfall for the season. An additional 2.2 inches of snowfall was measured on the 12th. Several temperature records were broken. A record low max of 16 degrees on the 11th broke the previous record of 19 set back in 1916. A record low max of 6 degrees on the 12th broke the previous record of 9 degrees…also set in 1916. The record low of -13 on the 12th…shattered the previous record of -4 degrees set back in 1872. Even more impressive…the record low of -14 degrees on the 13th broke the previous record of -3 degrees set back in 1916. The sudden drop in temperatures on the 10th…followed by several days of sub-freezing temperatures chilled trees to the core. The record drop in temperatures…preceded by mild fall temperatures…damaged or killed scores of trees across the I-25 Corridor and northeast plains. At the time…the trees were not finished with the hardening process that enables them to withstand winter weather. Many were instantly flash-frozen…and some would not show signs of damage until spring of 2015. Of the 2.2 million trees in the city of Denver alone…tens of thousands were killed from the November frost. Denver estimated a citywide loss of more than 10 million dollars.

11-12

In 1922…a major storm dumped 14.1 inches of snowfall over downtown Denver. The most snow on the ground was 10.5 inches at 6:00 pm on the 12th. North winds were sustained to 21 mph on the 11th. Temperatures were generally in the teens and 20’s.

In 1964…strong winds in Boulder caused power outages and minor damage. Winds gusted to 42 mph in downtown Boulder. At Stapleton International Airport west winds gusted to 36 mph on the 11th and 35 mph on the 12th.

In 1976…snow and freezing drizzle caused icing on bridges… Overpasses and some main roads. The elevated portion of I-70 was closed for a time during the afternoon of the 11th. Snowfall totaled only 0.8 inch at Stapleton International Airport…where northeast winds gusted to 20 mph on the 11th.

In 1989…the temperature climbed to a maximum of 76 degrees on both days…setting new record highs for each day.

In 1995…hurricane force downslope winds whipped across the Front Range foothills overnight. The National Center for Atmospheric Research in Boulder registered a peak wind gust to 124 mph with several more wind gusts over 100 mph. Utility poles and power lines were downed…leaving several hundred homes in Boulder without power. Windows were blown out of cars in Boulder. Other reports of strong wind gusts included: 108 mph atop Squaw Mountain west of Denver…104 mph at Table Mesa in Boulder…99 mph at Golden Gate Canyon… 85 mph at the Rocky Flats environmental technology site… 69 mph at Jefferson County Airport near Broomfield…and 62 mph in Lakewood. West-northwest wind gusts to 40 mph were recorded at Denver International Airport on the 12th.

In 2018…a period of moderate to heavy upslope snowfall to occurred in the Front Range Mountains and Foothills…and urban corridor mainly west of I-25. The foothills of Boulder and Jefferson counties received the greatest snowfall. Storm totals included: 14 inches…4 miles west of Boulder… Genesee and near Tiny Town; 13 inches…2 miles southwest of Boulder; 12.5 inches…4 miles northeast of Nederland; 12 inches near Roxborough State Park and Schaffer`s Crossing; 11.5 inches near Jamestown; 11 inches near Pinecliffe; 10.3 inches at the National Weather Service in Boulder; 10 inches near Conifer and near Niwot; 9 inches…4 miles east of Gold Hill; 8.5 inches near Greenland; 8 inches near Monument and Wheat Ridge; 7.5 inches near Louisville; with 5 to 7 inches in Arvada…Castle Rock…Erie…Lafayette…Longmont…Ken Caryl… and Rocky Flats. At Denver International Airport…2.6 inches of snowfall was observed.

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

In 1894…northeast winds were sustained to 42 mph with gusts to 48 mph behind an apparent dry cold front.

In 1903…west winds sustained to 40 mph with gusts to 45 mph warmed the temperature to a high of 57 degrees. A trace of snow was observed.

In 1922…heavy snowfall of 8.5 inches was measured over downtown Denver.

In 1974…strong winds gusting to over 80 mph caused local damage to houses and property along the foothills from Denver north. Automobiles…homes…and power lines suffered damage in Boulder. West winds gusted to 41 mph at Stapleton International Airport.

12-13

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

In 2011…hurricane force winds…up to 115 mph… downed trees in and power lines across the Front Range Mountains and Foothills. Scattered outages were reported in Gilpin County.  In Boulder…a woman received minor injuries when she was struck in the head by a falling tree limb. Three women near Georgetown received minor injuries when they were pelted by glass shards after a barrage of wind driven rocks and dirt shattered their windshield. Peak wind gusts included: 109 mph…6 miles north-northwest of Berthoud Pass; 101 mph atop Kenosha Pass…100 mph… 2 miles south-southwest of Loveland Pass; 99 mph…7 miles west-northwest of Berthoud; 92 mph at Blackhawk; 90 mph…3 miles south-southwest of Boulder; 87 mph…2 miles west-northwest of Aspen Springs and at Pickle Gulch; 84 mph at Loveland Pass and Lyons; 82 mph at the National Wind Technology Center; 80 mph at Dumont and 78 mph near Rollinsville and Ward. At Denver International Airport…west winds gusted to 52 mph on the 12th.

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.

In 2020…a peak wind gust to 60 mph was observed from the northwest at Denver International Airport…with a peak gust to 55 mph at Centennial Airport.

14-15

In 1917…overnight rainfall was 0.03 inch. This was the only measurable precipitation of the month…making it the 5th driest November on record.

In 1985…3 to 6 inches of snow fell across metro Denver. Snowfall totaled 3.8 inches at Stapleton International Airport where northeast winds gusted to only 13 mph.

In 2005…a winter storm that brought heavy snow to the mountains also spread heavy snow into the foothills to the west of Denver. Snowfall totals included: 14 inches at Aspen Springs…13 inches near Pinecliffe…and 12 inches near Nederland. Interstate 70 along with U.S. Highway 40 had to be closed near Idaho Springs due to snow…poor visibility in blowing snow…numerous accidents…and an increased avalanche danger. High winds were recorded in the foothills on the 14th. Winds gusted to 89 mph at Georgetown and to 91 mph on Sugarloaf Mountain west of Boulder. Strong microburst winds associated with a dissipating rain shower gusted to 61 mph at Denver International Airport on the 14th.

14-18

In 1964…the first measurable snowfall of the season totaled 6.0 inches at Stapleton International Airport where northeast winds gusted to 32 mph on the 14th. Most of the snow…4.2 inches…fell on the 14th. This was the only measurable snow of the month. Continue reading November 12 to November 18: This week in Denver weather history

November 5 to November 11: This week in Denver weather history

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:

2-5

In 1946…a major snow storm dumped 30.4 inches of heavy snowfall downtown and 31.0 inches at Stapleton Airport. The winter storm closed schools and disrupted all forms of transportation in the city. The greatest depth of snow on the ground was 28 inches at the airport. The duration of the snowfall…from 4:22 am on the 2nd to 3:08 am on the 5th… A total of 70 hours and 46 minutes…is the second longest period of continuous precipitation on record and the second heaviest snowfall of record at the time in Denver. The 17.7 inches of snowfall on the 2nd and 3rd was the greatest 24- hour snowfall ever recorded during the month of November. Buses and street cars had a difficult time…and many cars were abandoned along roadsides and streets for several days. Secondary roads in rural areas were blocked for 2 to 3 weeks. Several buildings in the city collapsed or were damaged from the weight of the heavy snow. Football games were canceled. Livestock losses were high over eastern Colorado. The precipitation from this storm alone exceeded the greatest amount ever recorded in Denver during the entire month of November previously. The precipitation recorded downtown was 2.03 inches…and the previous record for the entire month of November was 1.95 inches in 1922. North winds were sustained to 26 mph on the 2nd.

4-5

In 1933…the first measurable snow of the season totaled only 2.5 inches. This was the only measurable snow of the month. Northwest winds were sustained to 27 mph on the 4th.

In 1951…heavy snowfall of 5.7 inches was measured at Stapleton Airport where northwest winds gusted to 32 mph.

5

In 1896…west Chinook winds sustained to 44 mph with gusts to 46 mph warmed the temperature to a high of 56 degrees in the city.

In 1919…a rare November thunderstorm produced a mixture of rain and snow during the evening. Precipitation totaled only 0.14 inch with only a trace of snow. Northeast winds were sustained to 39 mph with gusts to 44 mph.

In 1948…a west-northwest wind gust to 50 mph was recorded at Stapleton Airport.

In 1994…winds gusted to 76 mph on the summit of Squaw Mountain…5 miles south of Idaho Springs.

In 2000…snow fell in the foothills west of Denver and across the southern suburbs. Snow totals included 6 inches near Evergreen…11 miles southwest of Morrison… And 7 miles south of Tiny Town and 5 inches in Aurora and Parker. Snowfall totaled 5.5 inches at the site of the former Stapleton International Airport. Northeast winds gusted to 26 mph at Denver International Airport where the visibility was reduced to 1/4 mile in heavy snow at times.

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.

In 2020…a peak wind gust to 63 mph was observed at Centennial Airport from the southwest. At Denver International Airport…a peak gust to 53 mph was observed. Continue reading November 5 to November 11: This week in Denver weather history

October 2023 weather recap: Overall a mild, dry month

Thornton, Colorado's October 2023 temperature summary. (© Tony's Takes)
Thornton, Colorado’s October 2023 temperature summary. (© Tony’s Takes)

The month of October was one without a lot of drama for Thornton. For the majority of it, we saw temperatures a good bit above normal and little precipitation. It was only in the last week of the month that we saw a taste of the cold and snow to come.

The first three weeks of the month were notable for the lack of precipitation. We saw streaks of eight days and 11 days without anything falling into the rain bucket. Similarly, with only a few days as exceptions, temperatures rain well above normal.

On the 26th, the weather pattern began to change and temperatures chilled out. This was followed by our first snowfall of the season, 4.9 inches on the 29th.

Overall, Thornton saw an average temperature for October 2023 of 51.2 degrees. This was a good bit above our 17-year running average of 49.6 degrees for the month. Temperatures ranged from a high of 86.8 degrees on the 20th down to a low of 14.4 degrees on the 30th.

For Denver, as measured at Denver International Airport, the month was similarly warm. The Mile High City saw an average temperature of 52.5 degrees, 1.4 degrees above the long term October average.

Precipitation was lacking for the month in both locations. Thornton managed a relatively meager 0.62 inches in the rain bucket with the majority of that coming with the end of month snowfall. Denver fared worse with 0.47 inches being collected there.

In terms of snowfall, there was only one event for the month. Thornton received 4.9 inches. Denver bested us with 7.5 inches as the storm system had bigger effects to the east and south of us. Thornton’s 17-year running average for October snowfall is 4.4 inches while Denver’s long term average is 3.9 inches.

Click here to view Thornton’s complete October 2023 climate summary report.

Thornton, Colorado's October 2023 precipitation summary. (© Tony's Takes)
Thornton, Colorado’s October 2023 precipitation summary. (© Tony’s Takes)

November 2023 preview: The transition to winter begins

Thornton's November weather previewThe weather during the month of November in Denver metro area can offer just about anything.  While it is normally a quiet month, it can be prone to extremes.

November has historically been one of Denver’s snowiest months and major snowstorms are not entirely uncommon.  However conditions can also be quite dry.

Temperatures during the month continue to cool as we get closer to winter and by the end of the month the low temperatures routinely dip to 20 degrees or below.  At times it can in fact bring conditions more like what we see in January.

Get all the details on November’s weather and what we can expect in our complete preview here.

Time to “fall back” as Daylight Saving Time ends Sunday, November 5

Daylight Saving Time
The United States returns to Standard Time at 2:00am Sunday as Daylight Saving Time comes to an end.

The biannual ritual of changing our clocks to adjust for Daylight Saving Time occurs this weekend, providing yet another signal of the changing of seasons.  The United States will ‘fall back’ one hour at 2:00am Sunday morning as we return to Standard Time.

The ritual of changing our clocks twice a year can be met with some resistance as some people struggle to adjust their body’s internal clock.  Others actually like the return to standard time as they get to enjoy an extra hour of sleep.

The time change definitely has big effects on the dawning of daylight and how early it gets dark in the evening.

Sunrise on Saturday occurs at 7:31am but on Sunday it will be at 6:32am. Similarly, sunset will occur at 5:54pm on Saturday but on Sunday the sun will disappear over the horizon at 4:53pm.

For many this means that when they get home from work it will now be dark and outdoor activities will be significantly curtailed as a result.

Arizona and Hawaii are the only states that do not observe Daylight Saving Time and remain on Standard Time year round.    The U.S. territories of Puerto Rico, American Samoa, Guam, Northern Mariana Islands, and the United States Virgin Islands also do not observe the event.

It won’t be all that long though before Daylight Saving Time returns.  On March 10, 2024 we will ‘spring forward.’

Daylight Saving Time Schedule

The mandated beginning and end of Daylight Saving Time has changed in the United States over the years.

The most recent schedule was set by the Energy Policy Act of 2005 and took effect in 2007.  We now ‘spring forward’ to begin Daylight Saving Time on the second Sunday in March and ‘fall back’ with the return to Standard Time on the first Sunday in November.

Daylight Savings Time Dates

Year DST Begins 2 a.m.
(Second Sunday in March)
DST Ends 2 a.m.
(First Sunday in November)
2023 12 March 2023 5 November 2023
2024 10 March 2024 3 November 2024
2025 9 March 2025 2 November 2025
2026 8 March 2026 1 November 2026
2027 14 March 2027 7 November 2027
2028 12 March 2028 5 November 2028
2029 11 March 2029 4 November 2029

October 2023 top shots: Monthly photo slideshow

The annular solar eclipse as seen from southern Utah. (Diana Mauzy)
The annular solar eclipse as seen from southern Utah. (Diana Mauzy)

October in Thornton can bring a wide variety of weather conditions, perfect for the photographer in all of us.

The month brings the changing of the colors at Colorado’s lower elevations and it is also is typically when we see our first freeze and first snow.

Couple those facts with our usual widely varying landscapes and wildlife and we have a month that is sure to bring in plenty of photo opportunities.

  • Slideshow updated October 31, 2023
  • To learn more about how to send your photo to us for inclusion in the slideshow, see below the slideshow.

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

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

[flickr_set id=”72177720311994744″]

What is missing in the slideshow above?  Your photo!

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

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

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

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

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

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

So come on, get those camera’s rolling!

October 29 to November 4: This week in Denver weather history

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:

27-30

In 2009…a powerful early season storm brought heavy snow to the Front Range. The combination of a deep northeasterly upslope flow coupled with abundant moisture and lift with the developing storm system produced an extended period of moderate to heavy snowfall. The heavy wet snow accumulated on trees and resulted in broken branches and scattered electrical outages. Interstates 70 and 76 were closed east of Denver. Numerous other roads and highways were shut down. The Red Cross set up numerous emergency shelters for stranded travelers. The blowing snow at Denver International Airport forced the cancellation of hundreds of flights. Schools were also closed. In the foothills storm totals included: 46 inches… 3 miles southeast of Pinecliffe; 42 inches…3 miles southwest of Conifer; 34 inches…3 miles north of Blackhawk; 30 inches at Aspen Springs and near Evergreen… 23 inches at Roxborough Park…and 20 inches…3 miles south-southeast of Morrison. Across the Urban Corridor storm totals included: 25 inches in Highlands Ranch; 21.5 inches near Louisville…20.5 inches in Broomfield…20 inches at Lafayette…17.5 inches in Boulder…17 inches in Westminster…16.5 inches in Erie; 15.5 inches in Arvada and 5 miles west-northwest of Littleton…15 inches in Littleton…14 inches in Englewood…13.5 inches in Lakewood and 6 miles north of Thornton; 13.3 inches at Denver International Airport…11 inches…4 miles south of Denver; 10.5 inches…2 miles north of Cherry Hills Village and Niwot.

28-29

In 1993…an upper level disturbance combined with a moist upslope flow to bring heavy snow to portions of metro Denver. Snowfall amounts ranged from 5.4 inches at Stapleton International Airport to 14 inches in Boulder. New snowfall totaled 8 inches at Gross Reservoir in the foothills 5 miles southwest of Boulder. On the 28th…north winds gusted to 30 mph at Stapleton International Airport where the temperature climbed to only 25 degrees on the 29th…equaling the record low maximum for the date.

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

In 1917…the all-time lowest recorded temperature in October…2 degrees below zero…occurred. This is also the earliest below zero reading of the season.

In 1939…the first measurable snow of the season totaled 5.6 inches in downtown Denver. Post-frontal northeast winds were sustained to 28 mph.

In 1961…heavy snowfall measured 6.0 inches at Stapleton Airport where northeast winds gusted to 30 mph.

In 1973…strong winds caused some damage to homes…stores… And utility lines along the foothills from metro Denver south.

In 1981…high winds buffeted the Front Range foothills with gusts to 55 mph in south Boulder.

In 1996…high winds gusting from 70 to around 100 mph blasted metro Denver. One man was killed when a strong wind gust overturned a pop-up camper onto him while he was trying to secure it. In addition…five people at the Rocky Flats Environmental Test Facility received minor injuries when several windshields were blown out of their cars…spraying glass onto the occupants. Several trees and power lines were also downed. Two 75-foot high pine trees were uprooted at the Mt. Olivet cemetery in Arvada. Property damage from the windstorm ran into the millions of dollars. The highest recorded wind gusts included: 101 mph at Jefferson County Airport near Broomfield…100 mph in Golden Gate Canyon…96 mph in Coal Creek Canyon…and 87 mph at upper Table Mesa in Boulder. West-northwest winds gusted to 43 mph at Denver International Airport. Insured damage from the wind storm totaled 5.2 million dollars…the third most costly storm of record in Colorado at the time.

In 2003…strong Chinook winds developed in and near the Front Range foothills. Winds gusting to 80 mph in Boulder downed several trees and power lines…causing damage and triggering scattered electrical outages. The combination of strong winds…very dry fuel conditions…and downed power lines sparked two large wildfires. The overland wildfire in Boulder County…near Jamestown…consumed nearly 3900 acres and destroyed 12 structures…including homes…trailers…and out-buildings. Preliminary damage estimates for the value of lost property was nearly one million dollars. In Douglas County…the Cherokee Ranch wildfire consumed 1200 acres and destroyed 4 structures. The large smoke plumes from both fires were highly visible across metro Denver. West winds gusted to 45 mph at Denver International Airport.

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.

In 2019…a strong storm system brought record breaking temperatures and up to a foot of new snow to parts of Denver…especially across the south and southeast portions of the metro area down to the Palmer Divide. In Denver… a record low maximum temperatures of 18 was set on the 29th… followed by a record low temperatures of 3 degrees on the 30th. The combination of snow and wind along the Interstate 70 corridor east of Denver forced its closure in both directions for several hours due to drifting snow and poor visibility. One weather related traffic fatality…occurred in the foothills west of Denver which closed State Highway 6. The official snowfall measurement at Denver International Airport was 7.7 inches. Numerous schools in and around the Denver area and to the east were closed due to heavy snow and hazardous road conditions. Cancellations and delayed flights at Denver International Airport left 800 passengers stranded at the airport overnight. Along the urban corridor and Palmer Divide storm totals included: Storm totals included: 12 inches at Ponderosa Park…10 inches near Foxfield; and Parker; 8.5 inches in southwest Aurora; near Buckley AFB…Cherry Creek…east Denver…and southwest Aurora; 8 inches in Boulder and near Elizabeth…Federal Heights…Louisville and Westminster; 7.5 inches near Castle Pines…7 inches in southwest Aurora and near Shamballa and Quincy Reservoir; 6.5 inches near Rocky Flats; 6 inches near Byers…Elbert…Greenwood and Lakewood. Continue reading October 29 to November 4: This week in Denver weather history

October 22 to October 28: This week in Denver weather history

This Week in Denver Weather History

It’s not quite Halloween but leading up to the holiday we see plenty of ‘scary’ weather in our look back at this week in Denver weather history. High winds are relatively commonplace and so too are major snowstorms. One recent event in 1997 dumped 14 to 31 inches of the white stuff on the metro area.

From the National Weather Service:

18-23

In 2003…an extended warm spell resulted in 5 new temperature records. The high temperature of 84 degrees on the 18th equaled the record high for the date. High temperatures of 86 degrees on the 19th…83 degrees on the 21st…and 84 degrees on the 22nd were record highs for the dates. Low temperature of 49 degrees on the 23rd was a record high minimum for the date. Low temperatures during the period were in the 40’s and lower 50’s.

19-23

In 1906…heavy snowfall totaled 22.7 inches in the city over the 5 days. Rain changed to snow on the evening of the 19th…and snow continued through the late afternoon of the 23rd. The heaviest amount of snowfall…16.0 inches…fell from 8:00 pm on the 20th to 8:00 pm on the 22nd. The most snow on the ground was 13.3 inches on the evening of the 23rd. This was the first snow of the season and the only snow of the month. Winds during the storm were from the north at sustained speeds of 20 to 30 mph each day. Temperatures during the storm were generally in the 20’s.

22

In 1878…winds were sustained to 42 mph.

In 1887…the first measurable snow of the season occurred… Ending the longest snow-free period in Denver…232 days… Since the last snow on March 5th.

In 1947…the first snow of the season totaled only 1.6 inches. Post-frontal north winds caused temperatures to plunge from a high of 60 degrees at midnight to a low of only 30 degrees 24 hours later. This was the only snow of the month.

In 1985…high winds gusting from 60 to 80 mph buffeted the Front Range foothills. The strongest reported wind gust was 89 mph in eastern Boulder. A treehouse east of Boulder was set on fire by a downed power line. Two people in Boulder were injured. A woman broke her arm when the strong winds knocked her to the ground. A carpenter in the city suffered a severely cut hand while he was trying to repair a roof that was being torn from a building. At Stapleton International Airport…northwest winds gusted to 41 mph.

In 2001…west-northwest winds gusting as high as 54 mph warmed the temperature to a high of 70 degrees at Denver International Airport.

22-23

In 1914…post-frontal rain changed to snow. Precipitation totaled 2.72 inches…most of which was in the form of moist snow which melted as it fell in the business section of the city. About 3 inches of snow was measured on lawns in the residential areas on the morning of the 24th. Official snowfall totaled only 0.4 inch downtown… But an estimated 8.0 inches of snow melted as it fell. North to northeast winds were sustained to 29 mph with gusts to 30 mph on both days.

In 1975…a vigorous cold front moving across metro Denver followed by strong northeast winds gusting to 52 mph produced billows of blowing dust and plunged the temperature 21 degrees in an hour. The surface visibility was reduced to 1/4 mile in blowing dust at Stapleton International Airport. The temperature cooled from a daily record high of 81 degrees to a low of 38 degrees by day’s end. The first snowfall of the season totaled 2.7 inches on the 23rd. This was the only measurable snow of the month at Stapleton International Airport.

In 1995…heavy snow fell on the Palmer Ridge south of Denver and in the foothills west of Denver where snow amounts ranged from 4 to 8 inches. Sedalia…south of Denver… Received 8 inches of snow. Winds strengthened on the plains and produced blizzard conditions…reducing surface visibilities to less than 1/4 mile. I-70 was closed from just east of Denver at Gun Club Road to the Kansas border. Ten inches of snow fell at Strasburg east of Denver where north winds at sustained speeds of 35 to 45 mph with gusts as high as 60 mph produced 2 to 4 foot drifts. Snowfall totaled only 2.2 inches at the site of the former Stapleton International Airport. North winds gusted to 51 mph at Denver International Airport.

23

In 1876…skies were fair…but winds were sustained to 48 mph.

In 1942…a major storm dumped 10.2 inches of snow over downtown Denver. Post-frontal northeast winds were sustained to only 13 mph.

In 1955…the first snowfall of the season and the only measurable snow of the month dumped 4.1 inches of snow on Stapleton Airport. This was the single heaviest October snowfall in 13 years since 1942. The storm also brought the first sub-freezing temperatures of the season when the temperature dipped to a low of 25 degrees.

In 1956…southwest winds gusted to 53 mph and produced some blowing dust at Stapleton Airport.

In 1967…a northwest wind gust to 51 mph was recorded at Stapleton International Airport. In downtown Boulder… Winds were sustained at 20 mph with gusts in excess of 40 mph.

In 1981…strong winds occurred in the foothills. Wind gusts to 70 mph were reported at Wondervu.

23-24

In 1887…the first measurable snowfall of the season totaled 3.1 inches. North winds to 20 mph were recorded on the 23rd. This was the only measurable snow of the month.

In 1932…post-frontal snowfall from the late evening of the 23rd continued through the late afternoon of the 24th and totaled 6.2 inches. Southeast winds were sustained to 25 mph with gusts to 26 mph on the 23rd. Temperatures cooled from a high of 68 degrees on the 23rd to a low of 25 degrees on the 24th…the coldest reading of the month that year. Many trees that had not shed their leaves became heavily laden by the wet snow. Many branches were broken… And a few trees toppled under the weight of the snow. The landscape became one of rare beauty.

23-25

In 2021…after several weeks of warm…windy and dry weather that fueled the two largest wildfires in the state`s history; a powerful storm system brought welcome relief as it produced heavy snow and frigid temperatures Denver and the Front Range. In the Front Range mountains and foothills… storm totals ranged from 10 to 20 inches. Along the urban corridor…storm totals from 4 to 12 inches were observed… with the heaviest amounts along and generally west of I-25 and over Weld County…where localized bands of heavy snow Some storm totals included 14.3 inches near Allenspark; and 12.9 inches in southeast Boulder and Nederland…with 12.8 inches near Loveland. At Denver International Airport…4.0 inches of snowfall was observed. Continue reading October 22 to October 28: This week in Denver weather history

Denver sets new record high temperature for October 20

Record High Temperature

We knew it was going to be unusually warm today and Mother Nature did not disappoint. In fact, the Mile High City broke a 73 year old record.

As measured at Denver International Airport, Denver’s high temperature today topped out at 86 degrees. This easily bested the previous record high for October 20th of 83 degrees set in 1950.

Here in Thornton, we lagged Denver much of the day but in the end, managed an extra degree above them, topping out at 87 degrees.

We will cool down about 10 degrees for the balance of the weekend. Conditions will remain dry and calm.

October 15 to October 21: This week in Denver weather history

This Week in Denver Weather History

Snow and wind are two common conditions we see this time of year and our look back at this week in Denver weather history certainly has those type of events. Also notable is a surprising October hail storm in 1998 that went into the books as one of the costliest in history.

From the National Weather Service:

13-16

In 1873…smoke from several large forest fires in the mountains made the air very hazy in the city.

15

In 1871…a terrible wind occurred during a snow storm in the foothills above Boulder. Damage was minor.

In 1878…high winds reached sustained speeds of 60 mph at times.

In 1911…post-frontal northwest winds were sustained to 41 mph with gusts to 43 mph.

In 1948…strong winds struck the Boulder area. Winds averaged 50 mph at Valmont just east of Boulder. Wind gusts in excess of 60 mph were recorded at the Boulder airport. Wind gusts to 40 mph briefly reduced the visibility to 1 1/2 miles in blowing dust at Stapleton Airport.

In 1980…a rare October tornado touched down in Boulder… Damaging a vocational training building and throwing three nearby cars together damaging them extensively. A mile and half away several camper vehicles were thrown 200 feet. The storm also produced 1 inch diameter hail in the Boulder area.

15-16

In 1928…a thunderstorm produced hail shortly after midnight on the 15th. Rain changed to snow by evening. Through the afternoon of the 16th…the heavy snowfall totaled 7.3 inches in the city. North winds were sustained to 23 mph on the 15th.

In 1984…the heaviest October snowstorm in several years hit eastern Colorado with a vengeance. The storm was known as the “Bronco Blizzard” since it occurred during a nationally televised Monday Night Football game in Denver. One to two feet of snow fell near the foothills in west metro Denver with 2 to 3 feet in the foothills. Wind gusts up to 55 mph whipped the snow into drifts as high as 4 feet. The storm closed schools…roads…and airports. I-70 was closed both east and west of Denver. I-25 was closed south to Colorado Springs. Flights were delayed for several hours at Stapleton International Airport. Power outages were widespread. Snowfall totaled 9.2 inches at Stapleton International Airport where north winds gusting as high as 40 mph caused frequent surface visibilities of 1/4 to 1/2 mile in moderate to heavy snow and blowing snow overnight. The high temperature of only 35 degrees on the 15th was a record low maximum for the date.

15-17

In 1989…an autumn snowstorm hit metro Denver with 2 to 6 inches of snow. Snowfall totaled 4.4 inches at Stapleton International Airport where the maximum snow depth on the ground was only 3 inches due to melting and north winds gusted to 25 mph on the 15th. The heavy wet snow caused leafy branches to sag onto power lines…resulting in a number of power outages. Five thousand homes were blacked out in Boulder on the 16th. Up to a foot of snow fell in the higher foothills with 19 inches recorded at Echo Lake.

16

In 1878…high winds reached sustained speeds of 60 mph.

In 1998…one of the costliest hail storms to ever hit metro Denver caused an estimated total of 87.8 million dollars in damage to homes…commercial buildings…and motor vehicles. At the time the storm was ranked as the 7th costliest ever. The hailstorm…rare for so late in the season…began over portions of Arvada…Wheat Ridge…and northwest Denver where mostly pea sized hail accumulated up to a depth of 6 inches near I-70. Several accidents were attributed… At least in part…to the hailstorm. Snowplows had to be called out to clear several city streets. The storm intensified as it moved to the east…into the Denver and Aurora areas. Large hail…up to 2.00 inches in diameter pounded east and southeast metro Denver. Two inch diameter hail fell in the city of Denver and at Buckley Field. Hail as large as 1 1/2 inches was measured in south Denver with 1 inch diameter hail in northern Aurora.

In 1999…upslope conditions produced snow across metro Denver with heavy amounts in the nearby foothills. Snowfall totals included: 9 inches at Eldorado Springs; 8 inches at Genesee… Golden Gate Canyon…Littleton and near Morrison; 7 inches near Nederland; and 6 inches in Louisville. Snowfall totaled 3.6 inches at the site of the former Stapleton International Airport.

16-17

In 1990…strong downslope winds raked the eastern foothills. Wind gusts from 60 to 75 mph were common. Strong winds in metro Denver resulted in wave damage to a dock used to moor several private sail boats at Cheery Creek Reservoir. Damage was confined to the dock and two anchor cables. A northwest wind gust to 43 mph was recorded at Stapleton International Airport.

17

In 1878…strong winds reached sustained speeds of 48 mph.

In 1988…a wind gust to 62 mph was recorded in central Boulder. The strong winds caused a few brief power outages. An old smoldering brush fire in the foothills west of Boulder was re-ignited by the wind gusts.

In 1994…winds gusted to 85 mph atop Squaw Mountain…5 miles south of Idaho Springs.

In 2006…a potent storm system brought heavy snowfall to the mountains and eastern foothills. Snowfall totals in the foothills included: 14 inches at Blackhawk…13.5 inches near Idaho Springs…13 inches at cabin creek…12.5 inches at Aspen Springs and Echo Lake…11.5 inches at Georgetown and Rollinsville…10.5 inches near Jamestown…and 10 inches at grant and Lake Eldora. Lesser snow amounts…from 4 to 9 inches…were recorded elsewhere in the foothills. Snowfall totaled only 3.5 inches in the Denver Stapleton area. At Denver International Airport…north winds gusted to 31 mph.

In 2012…A brief but powerful windstorm associated with a fast moving cold front across the Urban Corridor and adjacent plains during in the evening. Peak wind gusts ranging from 58 to 71 mph downed trees and power lines which damaged homes and vehicles. Several temporary structures were also damaged. Approximately fifty thousand were left without power in the Denver…Fort Collins and Greeley areas. Some schools were closed the following day until power could be restored. Around the Denver area…peak wind gusts included: 69 mph in Golden…64 mph at Littleton…62 mph at Buckley AFB and in Denver…near the intersection of Walnut St. and Interstate 25…and Longmont; 59 mph at Centennial Airport…58 mph at Denver City Park… Highlands Ranch.  At Denver International Airport…a peak wind gust to 35 mph was observed from the northwest.

17-19

In 1908…a moist…heavy…wet snowfall totaled 13.0 inches in downtown Denver over the 3 days. Rain from early morning on the 17th changed to snow by late afternoon and continued through the late morning of the 19th. Due to temperatures in the 30’s and melting…the most snow on the ground was only 5.0 inches at 6:00 pm on the 18th. Northwest to northeast winds were sustained between 12 and 20 mph during the storm. Precipitation totaled 1.82 inches.

18

In 1875…the haze was so dense that the mountains were not visible from downtown Denver for most of the day.

In 1937…a vigorous cold front produced north winds sustained to 32 mph with gusts to 41 mph. Rain and snow totaled 0.16 inch. Post-frontal snowfall of 0.8 inch was the only snowfall of the month.

In 1960…post-frontal upslope rain changed to snow. Snowfall was 2.2 inches at Stapleton Airport where precipitation (rain and melted snow) totaled 1.58 inches.

In 1971…wind gusts to 48 mph were recorded in downtown Boulder. West winds gusted to 30 mph at Stapleton International Airport.

In 1999…heavy snow developed in the foothills west of metro Denver with lesser amounts across the city. Snowfall totals included: 7 inches near Nederland…6 inches in Boulder…and 5 inches at Chief Hosa. Only 1.2 inches of snow were measured at the site of the former Stapleton International Airport.

18-23

In 2003…an extended warm spell resulted in 5 new temperature records. The high temperature of 84 degrees on the 18th equaled the record high for the date. High temperatures of 86 degrees on the 19th…83 degrees on the 21st…and 84 degrees on the 22nd were record highs for the dates. Low temperature of 49 degrees on the 23rd was a record high minimum for the date. Low temperatures during the period were in the 40’s and lower 50’s.

19

In 1887…northwest winds sustained to 42 mph were recorded in the city.

In 1982…3 to 6 inches of snow fell over northwest metro Denver…including Boulder. Only 1.2 inches of snowfall were recorded at Stapleton International Airport where north winds gusted to 35 mph. This was the first measurable snowfall of the season.

19-20

In 1990…an early winter storm dumped heavy snow across metro Denver. Snowfall amounts ranged from 4 to 8 inches in the foothills above 6500 feet elevation…4 to 7 inches in the Castle Rock area…and 2 to 5 inches across most of metro Denver and Boulder. Snowfall totaled 3.6 inches at Stapleton International Airport where northwest winds gusting to 48 mph kicked up some blowing dust shortly after a cold frontal passage on the 19th. However… Temperatures were warm enough to keep most roadways wet and slushy at lower elevations.

19-23

In 1906…heavy snowfall totaled 22.7 inches in the city over the 5 days. Rain changed to snow on the evening of the 19th…and snow continued through the late afternoon of the 23rd. The heaviest amount of snowfall…16.0 inches…fell from 8:00 pm on the 20th to 8:00 pm on the 22nd. The most snow on the ground was 13.3 inches on the evening of the 23rd. This was the first snow of the season and the only snow of the month. Winds during the storm were from the north at sustained speeds of 20 to 30 mph each day. Temperatures during the storm were generally in the 20’s.

20

In 1878…between 3:00 pm and 4:00 pm wind speeds averaged 48 mph with a maximum 1 minute sustained velocity to 96 mph at both 3:27 pm and 3:48 pm in downtown Denver. This is the highest sustained wind speed ever recorded in the city.

In 1986…a rare late October thunderstorm produced 3/4 inch diameter hail at centennial airport. Hail piled up 2 1/2 inches deep…causing some street flooding in south metro Denver.

In 2019…strong bora winds swept across the foothills and adjacent plains. Peak gusts included: 82 mph…3 miles southwest of Rocky Flats; 78 mph near White Ranch Open Space; 75 mph near Genesee and Georgetown; with 63 mph at Firestone. At Denver International Airport…a peak gust of 49 mph was observed from the west.

20-21

In 2007…a storm system brought heavy snow to the southern Denver suburbs as well as the palmer divide south of Denver. Storm totals included: 7.5 inches near Castle Rock…lone tree and greenwood village…with 6.5 inches at Elizabeth. Snow drifts up to 2 feet deep were observed 6 miles south-southwest of Elizabeth. In the Denver Stapleton area…2.0 inches of snow was observed.

20-22

In 1936…5.5 inches of snow fell over downtown Denver. Most of the snow…4.5 inches…fell on the 20th.

21

In 1920…the rare event of snow from a thunderstorm occurred in the city during the evening. Brilliant flashes of lightning and loud peals of thunder were first noted at 7:35 pm. Light rain began falling at 8:30 pm…and light moist snow began falling a few minutes later. Some soft hail was also seen falling with the rain and snow…but both melted almost as fast as they fell. The hail only continued for a few minutes…and the rain and snow ceased about 9:40 pm. The snowfall was the first to occur in Denver this season. The amount of precipitation at the station measured only 0.01 inch…but heavier amounts were reported from other parts of the city. Snowfall was only a trace.

21-22

In 1978…heavy rain on the 21st changed to snow by daybreak on the 22nd and continued the rest of the day. This was the first measurable snowfall of the season…but totaled only 1.7 inches at Stapleton International Airport where east winds gusted to 29 mph. While only a trace of snow covered the ground…precipitation totaled 1.27 inches.