Thornton, Colorado, USA
UpdatedSun, 13-Jun-2021 3:15pm MDT 


ThorntonWeather.com on Twitter

ThorntonWeather.com on Facebook


Weather Geek Stuff - weathergeekstuff.com

Rocky Mountain Weather Network

Tony's Takes Photography


Recent News and Posts

A beautiful spring day starts of Thornton’s workweek

Monday, May 24th, 2021 4:57am MDT

With a healthy dose of sun and temperatures right near normal, we are start off the week in fine fashion.

There is an outside chance some low clouds / fog will move in early but even if they do, it will dissipate later this morning leaving us with sunny skies for the balance of the day. Overall conditions will be calm and dry. High temperatures today will top out right near the average of 75 degrees for the date.

Tonight, skies will be mostly clear with lows in the mid-40s. What does the rest of the workweek hold? See here.

Join the Discussion - Post your commentJoin the Discussion!

Thornton’s weekend to remain mild, offer up some wind, a chance for storms

Friday, May 21st, 2021 4:53am MDT

We can look forward to pretty typical weather for this time of year this weekend. We will enjoy nice temperatures but also with some wind and possibly thunderstorms.

For Friday, with a healthy bit of moisture aloft mostly cloudy to partly sunny skies will be above. We will see some breezy winds, mainly in the afternoon into the evening. Look for high temperatures near the 80 degree mark. Tonight, partly clear skies will be above with overnight lows in the low 50s.

Saturday will again see a good bit of cloud cover. It will be cooler with highs in the mid-70s and again, some breezy winds. The afternoon brings just a bit of a chance for a thunderstorm. Saturday night, a few showers / thunderstorms may linger after dark. Overnight lows will again be in the low 50s.

Sunday will see the sun stage a return but, unfortunately, breezy winds will be around for much of the day. Look for highs in the mid to upper 70s. Have a great weekend!

Join the Discussion - Post your commentJoin the Discussion!

Very mild temperatures and lots of sun for Thornton’s Thursday

Thursday, May 20th, 2021 4:56am MDT

A fine spring day ahead for us. We will enjoy temperatures well above normal, blue skies and only a slight chance for a storm.

Sunny skies start us off and then we will see a few clouds later in the day but nothing too intrusive. A scattered thunderstorm may develop in the mid to late afternoon but these are not expected to be numerous or strong. High temperatures will be climbing to the upper 80s.

Tonight, skies will be partly cloudy and temperatures will drop to the low 50s.

Join the Discussion - Post your commentJoin the Discussion!

Wednesday sees a return of the sun, still will have a chance for thunderstorms

Wednesday, May 19th, 2021 6:05am MDT

Finally! A break from the gray. Today we will enjoy some of that blue above although we may still see an afternoon storm.

Mostly sunny skies start us off with partly sunny conditions being the dominant sky condition for the day. Temperatures today will be warming up nicely and topping out right near the average high for the date of 73 degrees.

The afternoon brings the typical chance for thunderstorms, mainly from 4:00pm to 7:00pm. Any storms that develop should be isolated and not too dramatic.

Tonight, any storm activity will settle down by about 8:00pm. Skies will become mostly clear and overnight lows will be in the upper 40s. Enjoy

Join the Discussion - Post your commentJoin the Discussion!

Tuesday to continue the cool temps, just a chance for showers

Tuesday, May 18th, 2021 4:51am MDT

Yesterday’s storms brought nearly a full inch of rain to Thornton (0.98 inches to be exact), a welcome drenching. Today, we will continue to be on the cool side but shower chances diminish a good bit.

Cloudy skies start us off then later this morning we will see some sun peek out. High temperatures will top out in the low to mid-60s.

A few sprinkles of rain will be possible this morning. The afternoon may see an isolated thunderstorm or two. Things look like they will be far more stable than yesterday so any storms that develop are not going to be as strong.

Tonight, mostly cloudy skies will be above and any showers will end by about 10:00pm. Overnight lows will be in the mid-40s.

Join the Discussion - Post your commentJoin the Discussion!

Cool temperatures, lots of clouds, some showers and thunderstorms for Monday

Monday, May 17th, 2021 5:22am MDT

We start of the workweek much like how we closed out the weekend. Cloud cover will be pretty consistent and some showers and thunderstorms can be expected.

Cloudy skies start us off this morning. The afternoon may bring a few breaks in the coverage. Light sprinkles of rain will be seen this morning but nothing that amounts to much.

This afternoon, if we can get enough heating to get convection going, will bring increased intensity of rain and thunderstorms. It is a bit of a wildcard though as to whether or not the ingredients come together. If they do, brief periods of rain, perhaps some small hail will be possible.

High temperatures today will top out in the low to mid-60s.

Tonight, some showers will persist through the night under cloudy skies. Overnight lows will drop to around 50 degrees.

Join the Discussion - Post your commentJoin the Discussion!

May 16 to May 22: This week in Denver weather history

Sunday, May 16th, 2021 5:42am MDT

This Week in Denver Weather History

Late spring typically brings some of the most eventful weather Denver sees throughout the year and our look back at this week in Denver weather history shows that.  There are many typical events we would expect to see such as hail, heavy rain and flooding, and even tornadoes.  Most notably, this week marks the two year anniversary of the Windsor tornado.  And, for those that think the snow is done, we can see that in 1983 a snowstorm struck the city forcing the closure of Stapleton International Airport.


In 1996…a period of unusually warm weather resulted in 4 record maximum temperatures in 5 days.  The record high temperatures were 87 degrees on the 14th…89 degrees on the 15th…and 93 degrees on both the 16th and 18th.  The temperature climbed to only 81 degrees on the 17th which was not a record.


In 1957…heavy snowfall totaled 8.8 inches at Stapleton Airport. The greatest amount on the ground was 3 inches.

In 1986…a spring storm dumped 1 to 2 inches of rain over metro Denver…but 2.71 inches fell at Buckley Field in Aurora.  Rainfall only totaled 0.84 inch at Stapleton International Airport.  Snow fell in the foothills with 7 inches recorded in Coal Creek Canyon southwest of Boulder.


In 1875…a heavy hail storm turned into heavy rain during the afternoon.  Rainfall totaled 0.86 inch in just 37 minutes…while the temperature dropped 22 degrees in 22 minutes.  Precipitation totaled 0.90 inch.

In 1894…west winds were sustained to 48 mph with gusts to 56 mph.

In 1949…a tornado was observed for 16 minutes…20 miles to the southeast of Stapleton Airport.  The tornado moved 5 miles to the northeast before dissipating.  No damage was reported.

In 1963…intense lightning started several forest fires in the foothills southwest of Denver near Deckers and Cheeseman Lake.  Little precipitation fell from the storms to alleviate the unusual dry conditions so early in the season.

In 1978…thunderstorm winds caused damage in southeast Aurora.  Winds of 60 to 80 mph blew down numerous fences and damaged several homes under construction.  High winds tore docks loose at Cheery Creek Reservoir…sinking 3 or 4 boats and damaging about 15 others.  At Stapleton International Airport where winds gusted to 60 mph…a 727 jet suffered 15 hundred dollars damage when wind toppled a runway light onto it.  The public reported an unconfirmed tornado 7 miles south-southwest of Stapleton International Airport.

In 1990…a line of thunderstorms moving across metro Denver uprooted a large ash tree…which fell and blocked the outside doors to a Denver elementary school…briefly trapping the students inside.  Thunderstorm wind gusts to 69 mph were reported at Jefferson County Airport. Northwest winds gusted to 44 mph at Stapleton International Airport.

In 1991…two tornadoes touched down briefly in Castle Rock… But no injuries or damage were recorded.  Heavy thunderstorm rains of 0.50 to 1.10 inches in a couple of hours caused Lena Gulch near Golden to flood.  No damage was reported.

In 1996…dry microburst winds of unknown strength overturned a trailer and damaged storage sheds in Strasburg east of Denver.


In 1981…a heavy rain storm dumped 1 to 2 1/2 inches of rain across metro Denver.  Rainfall totaled 1.27 inches at Stapleton International Airport where north winds gusted to 38 mph on 17th.

In 1983…a very strong late spring storm dumped heavy snow over the Front Range.  Strong winds with the storm produced blizzard conditions at times.  Sustained winds were 20 to 40 mph with a peak gust to 55 mph at Stapleton International Airport.  The foothills received 1 to 2 feet of snow with 4 to 12 inches along the foothills.  Howling winds whipped the snow into drifts several feet deep…closing schools and highways.  Stapleton International Airport was forced to reduce flight operations…closing 2 of 4 runways and stranding hundreds of travelers.  Most of the damage and inconvenience caused by the storm was in power outages… Which occurred when wind and heavy wet snow caused hundreds of power poles to snap and topple.  About 20 square miles of Denver were blacked out.  Precipitation from the storm totaled 1 to 3 inches.  At Stapleton International Airport… Snowfall totaled 7.1 inches with a maximum snow depth on the ground of only 2 inches due to melting.  The high temperature of 40 degrees on the 17th was a record low maximum for the date.  Due to the heavy moisture content of the storm…widespread street flooding occurred on the 18th when much of the snow melted under the warm May sun and temperatures climbed to a high of 57 degrees.

In 1995…significant moisture and upslope flow caused flooding across metro Denver.  Moderate to heavy rains… Which began on the evening of the 16th…developed in the foothills and spread eastward over metro Denver throughout the night.  The heavy rains brought many creeks and small streams to bankfull or slightly over.  Locations along the foothills received between 3 and 4 inches of rainfall from the storm.  Boulder received 3.60 inches of rainfall for the 24-hour period…causing minor street flooding near small streams.  To the northwest of Boulder…a bridge which crossed Fourmile Creek was washed out.  Numerous rock and mudslides occurred in foothills canyons…closing portions of U.S. Highways 6 and 40 and State Highway 119 for a few hours at a time.  Rocks were piled 6 feet deep on a stretch of State Highway 119 along with Boulders as large as cars on U.S. Highway 6.  A parking lot near a creek in Golden caved in leaving a hole the size of an 18-wheeler.  Rushing water washed out a 50-foot stretch of a road in Westminster. Rainfall totaled 1.75 inches at Denver International Airport…but only 1.42 inches at the site of the former Stapleton International Airport.


In 1903…southwest winds were sustained to 42 mph with gusts to 45 mph from an apparent microburst which produced only a trace of rain.

In 1960…hail to 3/4 inch diameter was measured in Thornton. Golf ball size hail fell in Arvada.

In 1972…microburst winds gusted to 51 mph at Stapleton International Airport.

In 1975…hail 1/2 to 3/4 inch in diameter fell over western metro Denver.

In 1978…a small tornado touched down in south Aurora damaging 40 homes…6 to a considerable extent.  One garage was demolished and blown across the street.  Parts of roofs were completely blown away.  Several 2×4-inch boards were blown into the sides of houses.  Another small tornado in Parker damaged two airplanes.  Other funnel clouds were sighted over Northglenn and near Golden.

In 1985…a thunderstorm produced a total of 1.50 inches of rain in Brighton where 0.72 inches fell in 40 minutes. Small hail covered the ground…and there was some street and basement flooding.

In 1987…small hail piled up 4 inches deep in southwest Aurora.  There was also widespread street flooding and a few power outages.  Hail as large as 3/4 inch in diameter fell at Castle Rock.

In 2000…high winds occurred along and east of the Front Range foothills…as a deep surface low pressure center formed over the northeast plains of Colorado.  An amusement park in north Boulder received about 25 thousand dollars in property damage.  Peak wind reports included:  88 mph at the national wind technology center…84 mph in Boulder…and 80 mph at the National Center for Atmospheric Research Mesa Laboratory. A powder keg of severe weather…including tornadoes and thunderstorms producing large hail…damaging winds and heavy rain…occurred over the plains to the northeast of Denver.  The only severe weather reported across metro Denver was 1 inch diameter hail in Littleton.


In 2017…a strong spring storm dropped across the Great Basin… and then moved eastward across Colorado. Isolated but strong thunderstorms preceded the system on the 17th with hail up to nickel size near Boulder Airport and Brighton. Significant snow fell across the Front Range mountains and foothills over the next couple of days. Along the Interstate 25 Corridor… rain turned to snow on the morning of the 18th…heaviest from around Broomfield northward. The heavy wet snow snapped the limbs of fully leaved trees and caused scattered power outages. A barns collapsed in northeast Loveland. Fifty-five head of cattle were inside the collapsed barn; three were injured and later euthanized. Numerous branches and trees snapped in the foothills. Elsewhere…several scattered smaller power outages were reported. Three to nearly five inches of liquid precipitation occurred…as rain or a mix of rain and snow…fell around Greeley. Storm totals in the Front Range mountains and foothills included: 42.0 inches near Allenspark…41.5 inches near Ward…36 inches at Estes Park… 32 inches near Pinecliffe…30.5 inches northwest of Golden… 30 inches near Nederland…26 inches near Breckenridge…25 inches near Aspen Springs and Bear Lake State Park…14 inches at Aspen Springs…with 9.5 inches near Evergreen. On the west side of the Interstate 25 Corridor…storm totals included: 10 inches near Superior and Louisville…6 to 8 inches in and around Fort Collins…6 inches in Lafayette… 5 inches in Broomfield and Loveland…and 4 inches near Niwot.


In 1864…heavy rains combined with melting snow to cause much flooding on north clear creek in Blackhawk.  Many bridges on the road to Denver were washed away by the high water on clear creek.

In 1893…northwest winds were sustained to 56 mph with an extreme velocity to 60 mph.

In 1960…large hail to 1 inch in diameter damaged roofs and cars in metro Denver.  Heavy snow and rain in the foothills caused rock and landslides…which blocked some highways. There was widespread minor damage from lightning. Hail as large as 1 1/8 inch in diameter was measured at Stapleton Airport where winds gusted to 44 mph.

In 1975…a tornado touched down briefly just south of Buckley Field in Aurora.  A few minutes later the same tornado touched down in open country 8 miles northeast of Stapleton International Airport.  No damage was reported.

In 1985…3/4 inch hail fell just southeast of Aurora.

In 1988…lightning started a fire at a home in the foothills west of Boulder…causing 50 thousand dollars in damage.

In 1995…strong thunderstorms rumbled across metro Denver dropping mainly pea to marble size hail.  However…hail stones as large as 1 1/4 inches in diameter fell in Wheat Ridge and downtown Denver.  Hail piled up to 2 inches deep in Wheat Ridge and northwest Denver.

In 1996…the buffalo creek wildfire started and spread rapidly on strong southwest winds at 20 to 30 mph.  Dry weather conditions contributed to the spread of the fire… Which burned nearly 12 thousand acres and destroyed 12 structures including some houses.

In 2001…a 19-year-old man was struck and killed by lightning as he was walking along the shoulder of U.S. Highway 36 in Westminster.

In 2003…hail to 3/4 inch in diameter was measured at Denver International Airport.

In 2010…a small tornado touched down near Firestone but did no damage.

» Click here to read the rest of May 16 to May 22: This week in Denver weather history

Join the Discussion - Post your commentJoin the Discussion!

Somewhat unsettled weather for Thornton’s weekend

Friday, May 14th, 2021 4:55am MDT

A relatively typical bit of weather for this time of year over the next few days. Temperatures will be comfortable but we will have some good chances for showers and thunderstorms.

Friday will be the warmest day of the period with highs in the mid-70s. Mostly sunny skies will be above and then this afternoon some scattered thunderstorm activity is expected. Tonight, any storms will be done by midnight and we will have partly clear skies above. Overnight lows will be in the mid-40s.

Saturday sees an increase in cloud cover with partly sunny skies. High temperatures will be around the 70 degree mark. The afternoon and evening bring some showers. Saturday night, showers will be ending and lows will be in the upper 40s.

Sunday brings our best chance for precipitation, mainly in the afternoon. Highs will be in the mid to upper 70s with partly sunny skies.

Join the Discussion - Post your commentJoin the Discussion!

Beautiful weather conditions on tap for Thornton’s Thursday

Thursday, May 13th, 2021 4:51am MDT

A fine-looking spring day ahead for us, finally. We will enjoy a good dose of sun today with temps a bit above normal.

Mostly sunny skies will be above throughout the day. Overall conditions will be calm and dry other than some breezy winds in the afternoon. High temperatures will top out in the mid-70s.

Tonight, partly cloudy skies will be above and lows will drop to the mid-40s. Enjoy!

Join the Discussion - Post your commentJoin the Discussion!

Calm, cool, dry conditions for Thornton’s Wednesday

Wednesday, May 12th, 2021 4:58am MDT

After a couple of days of wet, chilly weather, we begin to turn the corner today. Temperatures will warm, although remain cooler than normal, but conditions will be calm and dry.

Partly sunny skies and some areas of fog start us off. Cloud cover will quickly ease leading to mostly sunny skies for most of the day. High temperatures will top out around the 60 degree mark, about 10 degrees below normal.

Tonight, skies remain mostly clear with overnight lows dropping to the upper 30s.

Warmer weather more on par with what we expect this time of year lies ahead. Have a look at the extended forecast here.

Join the Discussion - Post your commentJoin the Discussion!