Thornton, Colorado, USA
UpdatedFri, 26-May-2017 10:05pm MDT 


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Thornton’s weekend to bring very mild temperatures, overall calm conditions

Friday, May 5th, 2017 5:28am MDT

Are you ready to get outside and get some of those spring chores done? Maybe go for a hike instead? Either way, this will be a great weekend to get all of that done.

Friday looks to be the day with the most sun but it also will be the least warm. Sunny skies will be above for the most part today with maybe a few high clouds late. Winds will be calm, conditions dry. Temperatures will be topping out close to the 80 degree mark. Tonight skies remain mostly clear and we will see lows near 50 degrees.

Saturday looks to be the warmest day of the three day period. Highs will be around 86 degrees under mostly sunny skies. We will remain dry and calm. Overnight Saturday into Sunday morning lows once again dip to near 50 degrees.

Sunday continues the warm weather but does see a little bit of unsettling. More clouds will mean partly sunny skies and the afternoon and evening bring a slight chance for showers and thunderstorms. Temperatures will still be mild with highs in the low to mid-80s.

Have a great weekend!

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May the Fourth brings pleasant spring conditions to Thornton

Thursday, May 4th, 2017 5:01am MDT

We don’t expect the Force has anything to do with the weather today but Mother Nature does and she is going to offer up a very nice day for us. Lots of sun will be above and we will see above normal temperatures, a pattern that will repeat at least through the coming weekend.

We start out the day with clear skies and temperatures right close to the freezing level. The mercury will begin rising soon after sun up and we will be on our way to an afternoon high in the low 70s. Sunny skies will be above throughout the day with only a few clouds late. Winds will be light and out of the northeast.

Looking ahead, we’ll warm up further tomorrow with highs near 80 degrees then follow that up with readings in the low to mid-80s Saturday and Sunday.

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Some showers possible early Wednesday, then we start to dry out

Wednesday, May 3rd, 2017 5:10am MDT

Today will be a bit of a day of transition as we shift from the cooler, damp conditions of recent days toward drier, warmer conditions. A few scattered showers will be possible this AM but by this afternoon those will be ending and the sun will stage a return.

We start out today with mostly cloudy skies and similar conditions above will be with us until late morning. By then, we should start to see the coverage break up and by sunset the clouds will be few and far between.

Some light shower activity will be possible for much of the day with the best opportunity coming from now through about noon. Only minimal amounts of precipitation are expected on areas that see it though.

Winds will be calm initially then become a bit breezy with gusts to 20mph or so possible out of the north. Temperatures will be heading toward a high around 60 degrees, possible a bit warmer depending on how quick those clouds move out.

Tonight, with the clearing skies, the mercury is going to dip close to the freezing level. As such, a Frost Advisory has been issued and will be in effect from 3:00am to 8:00am tomorrow morning. You’ll want to consider covering or bringing inside any sensitive vegetation.

After today, we will enjoy dry and very mild conditions lasting at least through the first of next week. Get more details in the extended forecast here.

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Thornton’s Tuesday weather to be a bit unsettled with clouds, chances for rain

Tuesday, May 2nd, 2017 5:16am MDT

Low pressure has setup across the region and that, coupled with a trough moving through, will lead to unsettled weather conditions today and tomorrow. While we do see chances for showers, perhaps with some thunder, we aren’t expecting the activity to amount to much.

We start out the day with mostly cloudy skies and then should see it become cloudy for the balance of the day with few opportunities to see the sun. Winds start out of the south but then will transition to northwesterly this afternoon while remaining relatively calm. We start out a little bit chilly this morning but then will warm up to a high right near the 60 degree mark. Not bad but also a good bit below the average for the date of 66 degrees.

We may see some light showers after about 9:00am with better chances coming from 1:00pm through tonight. There isn’t a lot of moisture so amounts, if any, shouldn’t be much. The atmosphere will be slightly unstable in the afternoon and evening so some thunderstorm activity may develop but again, if they do it isn’t expected to be anything extraordinary.

Have a great day and keep an eye out for the showers with our interactive radar here.

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April 2017 weather recap: Warmer temperatures, little snow but precipitation near normal

Monday, May 1st, 2017 5:30pm MDT

The month of April had a bit of a mixed bag for Thornton.  While we saw temperatures above normal and snowfall below normal, precipitation actually ended up right near Denver’s long term average.

We started out cool on the first day of the month, warmed up for two days, then were delivered our first snowfall of the month on the fourth day.  From there we saw a string of above normal temperatures, some far above, that lasted almost uninterrupted for two weeks.

Some rain finally fell for the three days beginning the 20th and temperatures cooled a bit.  Then, on the 28th, we received our second and final snowfall of the month and followed it up with a very cold day before rebounding on the final day of the month.

Thornton saw an average temperature during April 2017 of 49.6 degrees. This was a good ways above Denver’s long term average for the month of 47.4 degrees.  Out at the airport, they were cooler with an average of 48.9 degrees.

Thornton’s temperatures ranged from a maximum of 80.3 degrees on the 14th down to a low of 24.1 degrees on the morning of the 30th.  Denver saw similar extremes of 79 degrees, also on the 14th, and a low of 24 degrees on the 10th.

In terms of precipitation, Denver averages 1.71 inches during April.  Thornton was right there with the average at 1.70 inches in our rain bucket. At DIA, things were quite a bit drier with only 0.98 inches being recorded.

Snowfall lagged behind average for the month, especially at the average.  Denver recorded only 2.5 inches officially while here in Thornton we came in at 5.8 inches.  Once again this highlights the problems with having Denver’s official measurements kept so far from where they were taken historically and far away from population.

Click here to view Thornton’s April 2017 climate report.

Thornton, Colorado temperature summary for April 2017. (ThorntonWeather.com)

Thornton, Colorado temperature summary for April 2017. (ThorntonWeather.com)

Thornton, Colorado precipitation summary for April 2017. (ThorntonWeather.com)

Thornton, Colorado precipitation summary for April 2017. (ThorntonWeather.com)

From the National Weather Service:

244 AM MDT MON MAY 1 2017




                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
 HIGH              90   04/30/1992
 LOW               -2   04/02/1975
HIGHEST            79   04/14        90     -11       77  04/23
                        04/13                             04/22
LOWEST             24   04/10        -2      26       25  04/01
AVG. MAXIMUM     63.2              61.5     1.7     59.4
AVG. MINIMUM     34.5              33.3     1.2     35.1
MEAN             48.9              47.4     1.5     47.2
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      1               0.3     0.7        0
DAYS MIN <= 32     15              13.0     2.0       11
DAYS MIN <= 0 0 0.0 0.0 0 
 MAXIMUM 8.24 1900
 MINIMUM 0.03 1963 
TOTALS 0.98 1.71 -0.73 2.56 
DAILY AVG. 0.03 0.06 -0.03 0.09 
DAYS >= .01        10               9.1     0.9       10
DAYS >= .10         5               4.5     0.5        6
DAYS >= .50         0               0.9    -0.9        2
DAYS >= 1.00        0               0.5    -0.5        1
 24 HR. TOTAL    0.22   04/29 TO 04/29           04/15 TO 04/16
                                                          04/16 TO 04/16
                                                          04/16 TO 04/16
 STORM TOTAL       MM                                 MM
 (MM/DD(HH))            MM                    04/16(00) TO 04/16(00)
                                                 04/16(00) TO 04/16(00)6
                                                 04/16(00) TO 04/16(00)6

 TOTAL             MM   MM
TOTALS            2.5               6.8

HEATING TOTAL     478               529     -51      526
 SINCE 7/1       4803              5731    -928     5230
COOLING TOTAL       0                 1      -1        0
 SINCE 1/1          0                 1      -1        0

 EARLIEST     09/08/1962
 LATEST       06/08/2007
EARLIEST      04/01             10/07
LATEST                          05/05

AVERAGE WIND SPEED              11.6

AVERAGE SKY COVER           0.60
NUMBER OF DAYS FAIR            6
NUMBER OF DAYS PC             17


THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                1     RAIN                       1
LIGHT RAIN               10     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                1     SNOW                       3
LIGHT SNOW                7     SLEET                      0
FOG                      10     FOG W/VIS <= 1/4 MILE      4
HAZE                      2



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April 30 to May 6: This week in Denver weather history

Monday, May 1st, 2017 4:53pm MDT
This Week In Denver Weather History

April 30 to May 6: This week in Denver weather history

May can bring a variety of conditions from snow and cold to severe thunderstorms and flooding rains. Looking back at this week in Denver weather history we see where all of those events have made an appearance in our past.

From the National Weather Service:


In 1964…several weeks of dry weather and windy conditions across the Great Plains to the east caused noticeable suspended dust to invade metro Denver. At Stapleton International Airport east winds gusted to 28 mph and visibility was reduced to 5 miles.

In 1989…a late season snowstorm dropped 2 to 4 inches of snow across metro Denver with 6 to 12 inches in the foothills. Snowfall totaled 3.9 inches at Stapleton International Airport where northeast winds gusted to 23 mph and the greatest snow depth on the ground was 2 inches due to melting.

In 1991…a pacific storm dumped heavy wet snow across metro Denver. The foothills were hit the hardest where snowfall amounts ranged from 16 inches at Evergreen to 5 inches at Idaho Springs. Lower elevations of metro Denver received 5 to 9 inches of snowfall with 5 inches in Boulder and 7.0 inches at Stapleton International Airport where northeast winds gusted to 25 mph. The weight of the snow caused power lines to fall and tree limbs to snap…producing power outages in parts of Denver…Aurora…and Westminster.

In 1999…heavy snow fell overnight in the foothills above 7500 feet elevation. Snowfall totals included: 13 inches near Rollinsville…10 inches near Evergreen…8 inches at Blackhawk and Nederland…and 7 inches at Conifer. Only rain fell across the city with 2.13 inches recorded at Denver International Airport.


In 1954…a major storm dumped 10.1 inches of snowfall at Stapleton Airport. Most of the snow…7.5 inches…fell on the 29th and 30th. The maximum snow depth on the ground was 5 inches on the 30th due to melting. No strong winds accompanied the storm.


In 1896…northwest winds were sustained to 55 mph with gusts as high as 64 mph in the city.

In 1960…the minimum temperature dipped to 22 degrees at Stapleton Airport. The sub-freezing cold damaged fruit trees and some other crops in the area.

In 1967…west winds gusted to 51 mph at Stapleton International Airport. Winds were strong and gusty across all of metro Denver.

In 1972…hail 1/2 to 3/4 inches in diameter fell at Stapleton International Airport. Northwest winds gusted to 35 mph.

In 1980…a cold air funnel touched down several times near Louisville.

In 1983…mothball-size hail fell in Wheat Ridge.

In 1992…the all-time highest recorded temperature in April… 90 degrees…occurred. This is also the earliest 90 degree reading for the season. In addition…the temperature dipped to a low of only 56 degrees…setting a record high minimum for the date.

In 1995…hail…up to 3/4 inch in diameter…fell at Denver International Airport. The hail was soft…lasted for only 8 to 10 minutes…and caused no damage.

In 2002…drought conditions started to have an effect on greater metro Denver. April…normally the third snowiest month of the year in Denver averaging just over 9 inches of snow…ended with only a trace of snow…ranking the month… Along with previous Aprils…the 2nd least snowiest on record. The month ended with only 0.23 inch of liquid precipitation making the month the 3rd driest on record. Mountain snowpack was less than half of normal for this time of year. A statewide drought emergency was declared by the governor.

In 2003…a small tornado touched down 10 miles east of Hudson… But did no damage. Hail as large as 3/4 inch in diameter fell in Aurora near Cherry Creek.

In 2004…post-frontal upslope flow produced light snowfall across metro Denver. Snowfall was 4.0 inches at Denver Stapleton…while the temperature hovered in the lower 30’s all day. The high temperature was only 33 degrees…a record low maximum for the date. The low temperature of 30 degrees was not a record. North winds gusted to 20 mph at Denver International Airport.


In 1980…to the west of Denver…heavy rain changing to snow buried the foothills above 7 thousand feet in 4 to 8 inches of snow. Precipitation in the foothills ranged from 1 to 3 inches…which caused some local flooding. Rain fell at lower elevations. Rainfall at Stapleton International Airport totaled 1.05 inches from the storm.


In 1902…northwest winds were sustained to 68 mph with gusts as high as 74 mph in the city during the early morning. The apparent very strong Chinook winds warmed the temperature to a high of 78 degrees.

In 1912…south winds were sustained to 42 mph with gusts as high as 58 mph. South to southwest winds were strong all afternoon.

In 1935…a moderate duststorm blew into the city at around 2:00 pm on northwest winds sustained to 17 mph with gusts to 19 mph. Later in the afternoon…the dust receded to the east in advance of a rainstorm from the west.

In 1988…very strong winds behind a vigorous cold front produced a blinding dust storm that closed I-70 east of Denver. Northeast winds over metro Denver peaked to 45 mph at Stapleton International Airport…but only kicked up some blowing dust. The temperature plunged from a high of 76 degrees at midday to 36 degrees at midnight as light rain changed to light snow.

In 1991…3/4 inch diameter hail fell at Standley Lake in northwest metro Denver.

In 1999…heavy snow developed in the foothills above 7 thousand feet elevation. Snow totals included: 10 inches at Rollinsville…7 inches near conifer…and 6 inches atop Crow Hill. Rain fell across metro Denver.


In 1903…post-frontal rain changed to light snow overnight… But totaled only 2.0 inches. This was the last snow of the season. Northeast winds were sustained to 45 mph with gusts to 48 mph on the 1st.


In 1898…snowfall totaled 15.5 inches in downtown Denver. Most of the snow…6.2 inches…fell on the 3rd. Most of the snow melted as it fell. The greatest snow depth on the ground was only 2.5 inches on the 3rd at 8:00 pm. This was the only snowfall during the month. Northeast winds were sustained to 22 mph on the 1st.


In 1874…strong winds upset two railroad passenger coaches near Georgetown. The baggage was retrieved and placed in a heavy…large wagon. The passengers then seated themselves on top of the baggage. Another strong gust of wind upset the wagon. The driver’s shoulder was dislocated…and a passenger’s leg was badly injured. In Denver…northwest winds increased and blew in gusts and heavy winds were observed on the ridge tops. On the Kansas Pacific R.R. east of Denver…the wind was so strong that it blew the train back several lengths…which caused the train to be about 7 hours late arriving in the city.

In 1901…south winds were sustained to 50 mph with gusts to 60 mph from an apparent thunderstorm with hail.

In 1944…snowfall of 8.3 inches was accompanied by a thunderstorm. This was the last snowfall of the season and the only snow of the month. Northwest winds were sustained to 25 mph.

In 1955…southwest winds at speeds of 37 mph with gusts as high as 58 mph caused some blowing dust at Stapleton Airport.

In 1983…1 inch diameter hail fell a few miles south of Bennett.

In 1984…3/4 inch diameter hail fell in Northglenn.

In 1988…I-70 east of Denver was closed for the second straight day…this time due to snow and blowing snow producing up to 2 foot drifts. While only 2 to 4 inches of snow fell across metro Denver…Strasburg…just east of Denver…received a foot of snow. North winds peaked to 51 mph at Stapleton International Airport where snowfall totaled only 1.3 inches.

In 1995…lightning struck a house in Westminster sparking an attic fire.


In 1979…heavy rain changed to snow on the 2nd. Snowfall totaled 3.9 inches at Stapleton International Airport… Where northwest winds gusted to 26 mph. The greatest depth of snow on the ground was only 1 inch at midday on the 2nd due to melting. Total precipitation for the 2 days was 1.65 inches.


In 1987…a slow moving storm brought rain…wind…and snow to metro Denver. Rainfall totaled 1.04 inches at Stapleton International Airport where north winds gusted to 48 mph on the 3rd. The foothills received 5 to 10 inches of snow.


In 2001…a very slow moving pacific storm system became parked near the four corners region…which allowed heavy snow to develop above 6500 feet in the foothills with a mix of rain and snow over lower elevations of metro Denver. Snowfall totals included: 21 inches atop Crow Hill and at Idaho Springs; 19 inches near Blackhawk; and 18 inches in Coal Creek Canyon…Genesee…and 11 miles southwest of Morrison. Snowfall totaled 6.2 inches at the site of the former Stapleton International Airport. Precipitation (rain and melted snow) totaled 2.09 inches at Denver International Airport where north winds gusted to 30 mph on the 2nd.


In 1898…heavy snowfall of 6.2 inches fell over downtown Denver. Most of the snow melted as it fell. The greatest snow depth on the ground was 2.5 inches during the evening.

In 1907…the all-time lowest recorded temperature in the month of May…19 degrees…occurred.

In 1925…an apparent microburst produced sustained northeast winds to 44 mph with gusts to 52 mph. Rainfall was only 0.01 inch in downtown Denver.

In 1981…lightning struck 9 golfers at the south suburban golf course. None were injured seriously.

In 1983…hail 1 1/2 inches in diameter fell at Green Mountain west of Lakewood…with 3/4 inch stones reported in Lakewood.

In 1986…a thunderstorm wind gust to 51 mph was recorded at Stapleton International Airport.

» Click here to read the rest of April 30 to May 6: This week in Denver weather history

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Thornton’s May weather preview: Snow to severe storms

Monday, May 1st, 2017 4:14pm MDT
Thornton, Colorado May 2013 weather preview.

Thornton, Colorado May 2016 weather preview.

Colorado’s famously highly variable weather seems to showcase itself during the month of May when a variety of weather conditions can be seen.

Winter-like temperatures and snow are possible as are mid-summer like temperatures or the more typical spring severe weather.

As the month starts out in 2017 we see pretty typical conditions with a few cool, possibly damp days, before warming up to above normal levels.  Long range forecasts lean toward possibly wetter than normal conditions for the month overall but no overriding factors determining where temperatures will end.

The month can bring extremes.  Snow is not entirely uncommon during the month, oftentimes causing damage to newly bloomed trees.  More common however is severe weather, particularly in the latter half of the month.  Thunderstorms become more frequent and their associated hazards – lightning, wind, hail and tornadoes – are usual visitors.

For a complete look at what lies ahead for the month of May, check out our full preview here.

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Thornton’s workweek starts with a seasonal day, slight chance for showers

Monday, May 1st, 2017 5:13am MDT

Monday brings weather conditions that are pretty typical for the first day of May. Temperatures will be a bit below normal but there will be plenty of sun and just the slightest chance for showers in the afternoon.

We start out under mostly clear skies then will see clouds slowly increase in coverage through the morning leading to partly sunny skies in the afternoon and evening. Winds will be out of the northwest and just a touch breezy in the afternoon.

Temperatures start chilly but then will head toward a high in the low to mid-60s. Average for today’s date is 66 degrees. We may see a few scattered showers in the area this afternoon although most of the activity is expected to remain north of us.

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April 2017 top shots: Monthly photo slideshow

Saturday, April 29th, 2017 4:08pm MDT
An American Kestrel enjoys a warm, early April day at the Rocky Mountain Arsenal. (Shawn Jones)

An American Kestrel enjoys a warm, early April day at the Rocky Mountain Arsenal. (Shawn Jones)

April can be a tricky month weather-wise with everything from mild temperatures to snow to severe weather being possible.  The good thing about that is that it provides plenty of chances for great photos!

April marks a transition between winter and summer for most of the country but for Denver it is especially true as we can see a stunning variety of weather.

The proverbial April showers are certainly a possibility for Denver. Snow? Tornadoes? Thunderstorms? You bet – all can happen!

Throw in our usual wildlife plus the wide variety of birds that return to the Centennial State for the spring and summer and there is a lot going on.

  • Slideshow updated April 29, 2017. 
  • 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.

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!

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Thornton’s weekend to bring a return of wintry conditions, advisory issued

Friday, April 28th, 2017 5:26am MDT

Mother Nature will serve up a reminder to us that while the calendar may say spring, winter-like conditions can still occur. The storm will make it felt later Friday and last through Saturday before we clear up and dry out Sunday.

For today we start out with some sun but clouds will begin to intrude by late morning and by this evening it will be cloudy. We will hit our high temperature of around 50 degrees at noon then see the mercury start to descend from there. Winds will become a bit blustery this afternoon and evening as the system pushes its way through.

After noon a few rain showers will be possible then as temperatures drop, precipitation will transition to snow by this evening. Look for the hardest hitting part of the snow to come from about 6:00pm this evening through midnight. The snow will then continue overnight and through much of the day Saturday but be lighter in intensity.

By Saturday evening showers will be coming to an end although some light activity will be possible through Saturday night. Temperatures tomorrow will be cold with highs only in the mid to upper 30s.

The National Weather Service has issued a Winter Weather Advisory that will be in effect from 6:00pm this evening through 6:00pm Saturday. The agency calls for overall total accumulations of 3 to 6 inches for the Denver metro area. At the current time, we expect Thornton to be at the lower end of the totals, likely in the 2 to 4 inch range although the potential is there for more.

As with most storms this time of year, the snow is expected to be a heavy, wet one. That will have the potential to lead to travel issues, power outages and broken tree limbs.

Skies will gradually clear in the early morning hours Sunday and lead us to mostly sunny skies to close out the weekend. Temperatures Sunday will bounce back to the low 50s.

Keep a close watch and be careful in what will likely be deteriorating conditions tonight.  Our Winter Weather Briefing Page has all the latest.

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