Thornton, Colorado, USA
UpdatedThu, 20-Jan-2022 6:05am MST 


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Thornton’s weekend starts off mild and pleasant, will end chilly with a bit of a chance for a shower

Friday, October 29th, 2021 5:02am MST

Somewhat of a mixed bag of weather for us over the three day period. Friday and Saturday look to be relatively nice but a cold front will change things up for Halloween.

Today we will enjoy the nicest day of the weekend. Lots of sun will be above with highs around the 70 degree mark. Tonight, skies will remain clear with overnight lows in the mid-30s.

Saturday will offer up sunny skies initially, then just a few clouds late in the day. Highs will be in the mid-60s. There will be some breezy winds in the afternoon as a cold front arrives. Saturday night, clouds will be increasing and lows will dip to near freezing.

Sunday brings mostly cloudy to cloudy skies. Highs will only be in the mid-40s. The afternoon may bring a few sprinkles of rain with better chances after 6:00pm.

During trick-or-treat time from 6:00pm to 9:00pm, temps will be dropping from the low 40s to the mid-30s along and there will be a chance for rain.

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Cool, calm conditions for Thornton’s Thursday

Thursday, October 28th, 2021 4:51am MST

A pretty nice looking fall day on tap for us. We will enjoy lots of sun with calm conditions and temps right near average for the date.

Sunrise will reveal clear skies and those will remain with us throughout the day. Overall conditions will be calm and dry. High temperatures will top out right near the average high for the date of 61 degrees.

Tonight, skies remain clear as we head for a low in the mid-30s.

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October 24 to October 30: This week in Denver weather history

Wednesday, October 27th, 2021 5:14am MST

This Week in Denver Weather History

This year Denver is still waiting for its first snow and we have already passed the average date we see it (October 19).  That however isn’t always the case and October can bring monster snowstorms as we see in our look back at this week in Denver weather history.

From the National Weather Service:


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.


In 1956…southwest winds gusted to 56 mph and produced some blowing dust at Stapleton Airport.  A cold front produced a thunderstorm with 1/8 inch hail.  Rain later changed to snow.  Precipitation totaled only 0.11 inch and snowfall only 0.3 inch.

In 1973…strong winds raked the eastern foothills…causing damage in Boulder and Jefferson counties.  The heaviest damage occurred in the Boulder area where 20 to 25 mobile homes were hit…some power and telephone lines were blown down…and a store was damaged.  A wind gust to 76 mph was recorded in Boulder at the National Bureau of Standards. Northwest winds gusted to 46 mph at Stapleton International Airport.


In 1921…rainfall totaled 0.35 inch overnight behind an apparent cold front.  North winds were sustained to 40 mph with gusts to 46 mph on the 25th.  Temperatures plunged from a high of 73 degrees on the 24th to a low of 39 degrees on the 25th.

In 1923…rain overnight changed to snow during the morning. The heavy snowfall accumulated to 12.0 inches before ending on the morning of the 25th.  Post-frontal north winds were sustained to 22 mph with gusts to 23 mph on the 24th.

In 1997…one of the worst and deadliest blizzards of the decade developed over eastern Colorado as deep east to northeast flow associated with a vigorous upper level low pressure system over the Four Corners…combined with a strong arctic air mass over the central Great Plains. Snowfall totals across metro Denver ranged from 14 to 31 inches.  The heaviest snowfall occurred in the foothills west and southwest of Denver where 2 to 4 feet of snow were measured.  Sustained winds to 40 mph with gusts as high as 60 mph produced zero visibilities and extremely cold wind chill temperatures from 25 below to 40 below zero.  Winds whipped the snow into drifts 4 to 10 feet deep.  Several major and interstate highways were closed as travel became impossible.  Red Cross shelters were set up for hundreds of travelers who became stranded when they had to abandon their vehicles.  Four people died in northeastern Colorado as a result of the blizzard.  None of the deaths were in metro Denver.  At Denver International Airport…4 thousand travelers were stranded when the airport was forced to shut down.  At least 120 cars were abandoned along Pena Blvd….the only arterial leading into and out of DIA.  The blizzard cost air carriers at least 20 million dollars.  Thousands of cattle died in the storm over northeastern Colorado…resulting in losses totaling 1.5 million dollars.  Some of the more impressive snowfall totals included:  51 inches at Coal Creek Canyon; 48 inches at Silver Spruce Ranch…near Ward; 42 inches at Intercanyon…in the foothills southwest of Denver; 37 inches at Sedalia; 35 inches at Aspen Springs and Conifer in the foothills west of Denver; 31 inches at Eldorado Springs… Southeast Aurora…and Englewood; and 30 inches on Table Mesa in Boulder.  Snowfall totaled 21.9 inches at the site of the former Stapleton International Airport…setting a new 24-hour snowfall record of 19.1 inches for the month. Snowfall totaled only 14 inches at Denver International Airport where north winds gusted to 39 mph on the 24th. High temperature of only 21 degrees on the 25th equaled the record low maximum for the date first set in 1873. Low temperature of only 3 degrees on the 26th set a new record minimum for the date.


In 1925…a vigorous cold front produced north winds sustained to 42 mph with gusts to 52 mph.  Post-frontal snowfall was only 0.4 inch during the late afternoon and early evening.

In 1959…northwest winds gusted to 55 mph at Stapleton Airport.

In 1997…the high temperature warmed to only 21 degrees…the record low maximum for the month.  The same temperature also occurred on October 30…1991.


In 1996…4 to 6 inches of snow fell in the foothills west of Denver.  Only 1.5 inches of snowfall were measured at the site of the former Stapleton International Airport on the 26th.  This was the only measurable snow of the month at the site.  The snowfall produced icy and snowpacked highways…which resulted in a 50-to 60-car pileup on I-25 south of metro Denver.  West winds gusted to 33 mph at Denver International Airport.

In 2006…a winter storm brought heavy snowfall to metro Denver and the eastern foothills.  Total snowfall ranged from 12 to 22 inches over the higher terrain and 6 to 12 inches across metro Denver.  Northerly winds at sustained speeds of 20 to 30 mph with gusts as high as 47 mph at Denver International Airport whipped the snow into drifts 3 to 4 feet deep.  Many tree limbs snapped under the weight of the heavy…wet snow which also downed power lines… Leaving thousands of residents without power.  Storm total snowfall included:  25 inches near Aspen Springs…conifer… And Evergreen; 23.5 inches near Rollinsville; 23 inches in Idaho Springs; 22.5 inches near Blackhawk; 21.5 inches near Bailey; 19 inches near Bergen Park; 18 inches near Aspen Springs…Genesee…and Jamestown; 17 inches southwest of Boulder; 16 inches in Evergreen; and 15 inches near Georgetown and Perry Park.  Snowfall totaled 5.3 inches in the Denver Stapleton area.  At Denver International Airport…rain…including a thunderstorm…changed to snow on the evening of the 25th after a high temperature of 70 degrees.

In 2010…a storm system brought heavy snow to the mountains west of Denver. Storm totals included: 24 inches at the Eisenhower Tunnel…18 inches at Loveland Ski Area; with 16 inches at Arapahoe Basin.


In 1897…a major storm dumped 13.5 inches of snowfall over downtown Denver.  Rain changed to snow during the evening of the 25th and continued through mid-morning of the 27th. Most of the snow…12.0 inches…fell on the 26th when north winds were sustained to 36 mph and gusts were as high as 46 mph.  Temperatures during the storm were in the 20’s and lower 30’s.  Precipitation (rain and melted snow) totaled 1.21 inches.


In 1995…winds gusting from 100 to near 110 mph pounded the foothills northwest of Denver.  At Nederland winds gusted to 100 mph and to 70 mph in Coal Creek Canyon.  Atop Squaw Mountain west of Denver wind gusts to 108 mph were recorded.  The strong winds downed some trees and caused power outages.  West-northwest winds gusted to 47 mph at Denver International Airport.

In 2010…very strong winds during the day knocked down power lines in parts of Boulder. The downed electrical lines sparked a small brush fire near Columbine Elementary School. Strong wind gusts also damaged the tennis bubble at the Millennium Harvest House. In Northglenn. a tree was knocked down and caused minor damage to a mini-van parked nearby. Peak wind gusts included: 70 mph at Berthoud…67 mph at Rocky Mountain Metropolitan Airport in Broomfield… 63 mph at the Rocky Flats National Wind Technology Center and 59 mph at the NCAR Mesa Laboratory…3 miles southwest of Boulder. West winds gusted to 43 mph at Denver International Airport.

In 2011…a powerful early season storm brought heavy snow to the Front Range and adjacent plains. The heavy…wet snow caused extensive downed large branches and in some cases…entire trees. Massive power outages occurred from Fort Collins and Greeley south to Denver and the surrounding metro area. Most of the trees still had their leaves…which helped to catch snow and down trees under the weight of the moisture laden snow. Nearly two hundred thousand utility customers along the Front Range were without heat and electricity for several hours. The Red Cross opened four temporary shelters overnight until the power could be restored. The outages also forced the closure of the Boulder Criminal Justice Center the following day. The fallen trees and branches also caused extensive property damage to roofs and automobiles. In the Front Range mountains and foothills…storm totals included 19.8 inches…3 miles west of Jamestown; 18 inches…5 miles west of Copper; 13 inches…3 miles north of Blackhawk and 3 miles south of Evergreen…4 miles east-northeast of Nederland and Lake Eldora; 12 inches at Berthoud SNOTEL. Across the Urban Corridor storm totals included: 11.5 inches in Boulder; 9.5 inches at the National Weather Service in Boulder; 9 inches…1 mile southwest of Westminster; 8.5 inches in Broomfield… Denver International Airport…Frederick and Louisville; 8 inches in Aurora…7 inches in Watkins; with 6 inches in Arvada.

» Click here to read the rest of October 24 to October 30: This week in Denver weather history

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Lots of sun Wednesday but with cool temps and breezy winds

Wednesday, October 27th, 2021 5:02am MST

Thornton will enjoy a lot of clear, blue skies above today but with cool temperatures. Most notable will be breezy winds, particularly in the afternoon.

The day starts off with sunny skies and those will remain throughout the day. Temperatures start out cold and then we will see warming to the mid to upper 50s. The jet stream is setting up overhead and that is going to lead to breezy / windy conditions. This afternoon, gusts to 35mph or so will be possible.

Tonight, winds will be easing by sunset, then become calm before midnight. Overnight lows will be around the freezing mark under mostly clear skies. Keep an eye on the temps and winds with our live weather gauges here.

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Tuesday starts out warm, cold front later to cool it down, bring chance of showers

Tuesday, October 26th, 2021 5:04am MST

We will start off the day relatively mild but by the latter half of the day, the picture changes. A cold front will be pushing through and with it, cooler temps, breezy winds and some showers.

Sunrise will see partly clear skies with relatively warm temperatures. Cloud cover will be increasing from mid-morning through the afternoon as a front pushes through. With the front, winds will be picking up steadily and be breezy for much of the day.

Temperatures will top out near the 70 degree mark right around noon but then start to drop. Scattered showers will develop after noon and last into the evening. Unfortunately, we are not expecting much out of these.

Tonight, cloud cover will begin to ease but breezy winds will continue for much of the night. Overnight lows will be in the mid-30s.

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Monday to offer up mild temperatures but with some breezy winds

Monday, October 25th, 2021 5:12am MST

Thornton’s workweek starts off in pretty descent fashion. We will enjoy very mild temperatures although there will be some wind that will bring along increased fire danger.

Partly clear skies start us off then by mid to late morning, the cloud cover will ease. High temperatures today will top out in the mid to upper 70s. Winds will be picking up this afternoon then settle down in the evening.

Those winds coupled with low humidity and dry fuels have prompted a Red Flag Warning to be issued. Please be very careful.

Tonight, skies will be largely clear with some breezy winds after midnight. Overnight lows will be in the mid-40s. Keep an eye on the temps and wind here.

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Winter Weather Preparedness Week recap

Saturday, October 23rd, 2021 4:30am MST
Winter Weather Preparedness Week concludes. Are you ready for winter?

Winter Weather Preparedness Week concludes. Are you ready for winter?

As we have talked about this week, winter weather can be dangerous and downright deadly.  However, being prepared helps to ensure that you and your family remain safe when the snow starts to fly or other winter weather conditions occur.

It is very easy to ignore the dangers of weather – no matter the season – and find yourself saying, “I wish I would have….” Now is the time to think about how you can prepare for these conditions, before it is too late and you find yourself wishing you had.

In this sixth and final message in a series on Winter Weather Preparedness from the National Weather Service, ThorntonWeather.com reviews the topics we covered this week and directs you to the previous articles and other resources to help you get ready.

600 AM MDT SAT OCT 23 2021

Enjoy the great outdoors in Colorado this winter season, but watch the weather.

The National Weather Service issues a variety of winter weather, outlooks, watches, warnings, and advisories, covered earlier during this Winter Weather Preparedness Week.  Safety tips were also passed along.

» Click here to read the rest of Winter Weather Preparedness Week recap

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Thornton’s weekend starts off warm then cool down closer to normal

Friday, October 22nd, 2021 4:56am MST

The three day period starts on the upside with mild conditions but then a passing system will serve to cool us down.

For Friday, mostly sunny to sunny skies will be above. Temperatures will be pleasant with highs in the low 70s. Tonight, partly cloudy skies will be above with lows in the upper 30s.

Saturday, a system passes through that will lead to increased cloud cover and cooler mercury readings. Look for highs in the mid-60s under mostly cloudy skies. Saturday night, mostly cloudy skies will be above with overnight lows around 40 degrees. There is just a slight chance for an overnight shower of rain.

Sunday sees the sun return but temperatures will be cooler. Highs will be in the low to mid-60s under sunny skies.

Have a great weekend!

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Avalanche safety – Be prepared or die

Friday, October 22nd, 2021 3:40am MST
Avalanches claim lives every year in Colorado. Before you head to the mountains, be sure you are prepared! (Wikimedia Commons)

Avalanches claim lives every year in Colorado. Before you head to the mountains, be sure you are prepared! (Wikimedia Commons)

As snow starts to fall, many Coloradoans and out of state visitors will take advantage of it and head to the mountains for a variety of outdoor activities.  Whether skiing, snowshoeing, or hiking, anyone who spends time outdoors in the high country needs to be aware of the danger avalanches present.  On average six people die in Colorado every year from avalanches and being prepared is an essential survival skill.

In this fifth in a series on Winter Weather Preparedness from the National Weather Service, ThorntonWeather.com helps you understand avalanches, where they occur, how to protect yourself and where to go for more information.  If you are headed to the high country, be sure to check out our Avalanche Information & Forecast page.

600 AM MDT FRI OCT 22 2021

Avalanches – Are you prepared?

Thousands of avalanches occur each winter in the mountains of Colorado. With the enormous popularity of winter sports in Colorado, this poses a risk to skiers, snowboarders, snowmobilers, and people traveling in the backcountry. On average 6 people die in Avalanches in the state of Colorado every year. Anyone who travels into the high country in the winter should be prepared for avalanches And know how to avoid them.

The most important thing to know is how to get information on current avalanche conditions. Check the Colorado Avalanche Information Center website at http://avalanche.state.co.us/ for the current avalanche forecast and the National Weather Service website http://www.weather.gov for the current weather forecast in your area. Knowing the current and future conditions will help you make good decisions in the backcountry.

A little information about avalanche safety can go a long way. Most avalanches occur during or just after snowstorms on a slopes between 30 to 45 degrees. A significant snowfall may result in an unstable snowpack. By waiting at least 36 hours after a big snow or wind storm before you go into the mountains the Snow may become more stable and less likely to avalanche. If you stay in valleys away from avalanche chutes, in stands of dense trees, or on gentle slopes you can decrease the risk of being caught in an avalanche.

If you are a skier or snowboarder at a commercial ski area the risk from avalanches is lower than in the backcountry. Ski patrols work to reduce the chance of an avalanche on open slopes. Respect the rules of the ski area, stay on open slopes, and do not stray out of bounds or into closed areas. The avalanche risk is higher outside of the ski area boundaries.

If you want to enjoy the great outdoors in areas prone to avalanches…You can reduce the danger by following a few simple rules:

  • Check the current avalanche forecast to get information on current and forecast avalanche conditions. Also check the latest weather forecast to see if conditions are likely to change while you are in the backcountry.
  • Never travel alone. Always have one or more companions. Even small avalanches can be fatal. If you are alone and get trapped, you may not be found until spring.
  • If crossing a slope that may be prone to avalanches, do it one person at a time. You want to minimize the impact on your party if an avalanche is accidentally released.
  • In avalanche country, all members of your party should carry avalanche rescue equipment including an avalanche beacon, shovel and probe pole. This increases your chances of a successful rescue and finding your friends alive.

Avalanche conditions in Colorado are monitored and forecasted by the Colorado Avalanche Information Center, CAIC. You can get more information on avalanches, avalanche forecasts, avalanchesafety and request a safety class from CAIC. Go to their website…Http://www.colorado.gov/avalanche or call the center at 303-499-9650.

Winter Weather Preparedness Week continues through Saturday. Now is the time to get prepared for winter so you can safely enjoy the outdoors and travel safely when the snow flies.

Avalanche Safety Tips

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Thursday to offer temps a bit above normal, increased clouds

Thursday, October 21st, 2021 4:56am MST

Not too shabby of a day ahead for Thornton. Temperatures will be at or a bit above average but we will see some clouds above.

Mostly clear skies start us off but then an increase in moisture aloft will lead to partly sunny skies for much of the day. Cloud cover will ease in the late afternoon. Overall conditions will be calm and dry. Highs today will top out in the mid-60s.

Tonight, skies will clear and lows will be in the mid-30s.

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