Thornton, Colorado, USA
UpdatedFri, 24-Feb-2017 11:55pm MST 


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Thornton’s Thursday cools slightly, remains dry

Thursday, November 10th, 2016 5:10am MST

Courtesy of a weak cold front, we will see temperatures cool a bit versus what we saw yesterday and tomorrow will cool even further. However, we will still have plenty of sun above and conditions will remain dry.

We start out the day with sunny skies and while there will be a few clouds by mid to late afternoon, there will be shortage of sun. Temperatures will be topping out in the mid to upper 60s. As the front pushes through in the early afternoon, winds will become a bit breezy with gusts toward 20 mph or so.

Tomorrow we’ll see highs cool further and actually come within a few degrees of average before rebounding back to the mid to upper 60s for the weekend. More details in the extended forecast.

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Lots of sun, very mild temperatures for Thornton’s Wednesday

Wednesday, November 9th, 2016 5:36am MST

A very simple weather forecast for us today that pretty much repeats the dominate theme of the past month or so. We will start out the day with some chilly mercury readings but warm up to a high of around 72 degrees. This is well above the average for the date of 55 degrees. Look for sunny skies throughout the day and dry, calm conditions overall.

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Election Day brings sunny skies, mild temperatures

Tuesday, November 8th, 2016 5:03am MST

There certainly is no reason weather-wise for you to not vote today if you haven’t already. Thornton will enjoy yet another day of above normal temperatures and clear, blue skies above.

We start out the day quite chilly having bumped into the freezing mark overnight. Temperatures will warm pretty quickly though once the sun comes up and we’ll see a high in the mid-60s. Winds will be calm, conditions dry.

While our weather clearly won’t impact the election, it may in other parts of the nation. Get the story here.

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Weather and Election Day: Will Mother Nature play a role in the outcome?

Monday, November 7th, 2016 12:39pm MST
Weather – The true determining factor of who will be president?

Weather – The true determining factor of who will be president?

We oftentimes hear about how weather can affect voter turnout but is there truly a link?  If there is, who does it benefit – Republicans or Democrats?  Studies seem to indicate that what might be thought of as an urban myth is indeed true and could in fact play a role in 2016.

In 2005, political science researchers Brad Gomez, Thomas Hansford and George Krause completed the first comprehensive study on the correlation between weather and voter turnout.  Their paper, “The Republicans Should Pray for Rain:  Weather, Turnout, and Voting in U.S. Presidential Elections” confirmed the conventional wisdom that weather does affect voter turnout, bad weather benefits Republicans and most interestingly, two presidential elections in the last 60 years may have had different results had the weather been different.

Looking back at presidential elections from 1948 to 2008, the study takes into account the weather in 3,000 U.S. counties.  They in turn looked at key areas of the nation and how weather, good and bad, affected voter turnout.  In the end, the study determined that precipitation is the key weather condition to affect voter turnout.

» Click here to read the rest of Weather and Election Day: Will Mother Nature play a role in the outcome?

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More of the same mild, dry conditions start the workweek

Monday, November 7th, 2016 5:01am MST

There will be no real change in Thornton’s weather Monday as we will continue with the unseasonably warm temperatures and dry conditions of recent weeks. In fact, those same conditions will be with us throughout the week.

For today we start out with a few clouds but those will give way to sunny skies by this afternoon. Temperatures will be warming up nicely to a high in the mid-60s. Conditions will remain dry, winds calm.

For the balance of the week, look for more of the same with highs in the mid to upper 60s, perhaps even a 70 degree reading on Wednesday. More details in our extended forecast.

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November 6 to November 12: This Week in Denver Weather History

Sunday, November 6th, 2016 4:32am MST
This Week In Denver Weather History

November 6 to November 12: 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:


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.


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.


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.


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.


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


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 1897…west winds were sustained to 45 mph with gusts as high as 50 mph in the city.

In 1919…post-frontal heavy snowfall totaled 8.4 inches over downtown Denver. Most of the snow…6.6 inches…fell on the 9th. North winds were sustained to 26 mph with gusts to 30 mph on the 8th.

In 1950…a major winter storm dumped 10.4 inches of snow at Stapleton Airport with the most snow…7.8 inches…falling on the 8th. East winds gusted to 31 mph at Stapleton Airport on the 8th. Snowfall totaled 8.2 inches in downtown Denver.

In 1958…strong winds caused some damage in Boulder. West- northwest winds gusted to 40 mph at Stapleton Airport on the 8th.

In 1975…heavy snowfall hit metro Denver. Snowfall at Stapleton International Airport totaled 8.0 inches and east winds gusted to 21 mph. Power outages caused by the storm affected over 10 thousand people in metro Denver.

In the foothills west of Denver…10 to 15 inches of snow fell. The storm produced the greatest 24-hour precipitation…1.29 inches…ever recorded during the month of November in the city.

In 1983…metro Denver received 4 to 8 inches of snow with the heaviest amounts near the foothills. It was the first measurable snow of the season in Denver. Only 1.8 inches of snow fell at Stapleton International Airport where north winds gusted to 20 mph.

In 1989…strong winds hit the Front Range. On the 9th…the wooden frame of a house under construction in Boulder was blown down. The previous evening a power outage blackened Nederland. Wind gusts to 95 mph were recorded 4 miles south of Rollinsville with 97 mph on Fritz Peak near that town. At Stapleton International Airport…northwest winds gusted to 45 mph on the 8th and to 38 mph on the 9th.

In 1998…another upslope snow event developed in the Front Range foothills. The heaviest snowfall occurred in west central Jefferson County where 14 inches were measured 8 miles west of Conifer. Other snowfall totals included: 10 inches at Evergreen and 9 miles northwest of Bergen Park; 9 inches at Genesee…Nederland…and near the Chief Hosa exit on I-70; and 8 inches in Coal Creek Canyon. On the 9th…snowfall was 2.6 inches at the site of the former Stapleton International Airport. North-northeast winds gusted to 30 mph at Denver International Airport on the 9th.


In 1985…Indian summer came to an abrupt end when a winter storm dumped 10 to 18 inches of snow in the Front Range foothills and 6 to 10 inches across metro Denver…snarling traffic and causing flight delays of up to 3 hours at Stapleton International Airport. The temperature plunged from a high of 66 degrees on the 8th to a low of only 13 degrees on the 9th…after the passage of a vigorous cold front with northeast winds gusting to 32 mph. The temperature climbed to only 19 degrees on the 10th…setting a record low maximum for the date. Snowfall totaled 7.3 inches at Stapleton International Airport with most of the snow…7.1 inches…falling on the 9th.

» Click here to read the rest of November 6 to November 12: This Week in Denver Weather History

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Thornton’s November 2016 preview: Will we break out of the warm, dry pattern?

Friday, November 4th, 2016 7:38am MST

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 is Denver’s second snowiest month 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.

Certainly given how warm and dry we were in October, we could use some relief.  Will that happen?

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

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Above normal temps, dry, calm conditions for Thornton’s weekend

Friday, November 4th, 2016 4:57am MST

Another pleasant fall weekend is on tap for us as temperatures remain much warmer than normal. A passing low pressure system will provide a brief but minor change to the pattern Saturday.

For Friday we start out chilly but will then be warming up nicely. Look for highs today right around the 70 degree mark. Sunny skies start things off then this afternoon we will see a few clouds but nothing intrusive.

The previously mentioned low pressure system will pass to our south on Saturday. Its impact on us will come in the form of increased cloud cover and slightly cooler temperatures. Look for highs in the mid-60s under mostly cloudy skies.

Sunday bounces right back as that system moves to our southeast. High temperatures will be back to around 70 degrees under mostly sunny skies.

Have a great weekend!

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October 2016 weather recap: An exceedingly warm and dry month

Thursday, November 3rd, 2016 8:11am MST

High pressure was the dominant weather feature for the month of October and that led to a pattern that blocked off moisture and kept temperatures well above normal.  Record-setting highs were made while precipitation was a rare event.

The historical average monthly temperature for the month of October in Denver is 50.9 degrees.  That number was easily eclipsed.  Here in Thornton we saw an average temperature of 55.8 degrees.  Out at DIA where Denver’s official numbers are kept, it was much warmer with an average of 57.8 degrees.

Both averages for October 2016 were far above normal.  Officially the month was so warm it became the fourth warmest October on record in Denver.  The number one spot was quite secure though with an average of 59.9 degrees back in 1950.

Temperatures in Thornton ranged from a high of 84.8 degrees on the 16th down to a low of 27.1 degrees on the morning of the 20th.  Out at the airport, the warmest reading was 86 degrees and the lowest 25 degrees, both on the same days that Thornton saw its warmest and coldest readings.

Denver recorded four record daily high temperatures during the month.  The first record high came on the 15th of the month to be followed by records on the 27th and 28th then a tie for the record high on the 31st.

In terms of precipitation, the same high pressure that kept things warm, kept things dry as well.  Thornton recorded a mere 0.43 inches in its rain bucket, all during the first half of the month. The airport was a bit drier with 0.26 inches recorded.

On average Denver receives 1.02 inches of precipitation in October so both locations were far below normal.  While it was certainly dry, it was not so much so that it was a record-setter as the month failed to make it into the top 20 driest Octobers.

No snow was recorded during the month so we are still awaiting that first event of the season.  This however is not entirely unusual as historically, 27% of Denver’s October fail to see any of the white stuff.

Click here to view Thornton’s October 2016 climate report.

Thornton, Colorado's October 2016 temperature summary. (ThorntonWeather.com)

Thornton, Colorado’s October 2016 temperature summary. (ThorntonWeather.com)

Thornton, Colorado's October 2016 precipitation summary. (ThorntonWeather.com)

Thornton, Colorado’s October 2016 precipitation summary. (ThorntonWeather.com)

From the National Weather Service:

244 AM MDT TUE NOV 1 2016




                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
 HIGH              89   10/16/1991
 LOW               -2   10/29/1917
HIGHEST            86   10/16        83       3       87  10/11
LOWEST             25   10/20        22       3       28  10/28
AVG. MAXIMUM     74.5              65.3     9.2     70.1
AVG. MINIMUM     41.2              36.6     4.6     42.8
MEAN             57.8              50.9     6.9     56.5
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      0               0.4    -0.4        0
DAYS MIN <= 32      3               8.5    -5.5        1
DAYS MIN <= 0       0               0.0     0.0        0

 MAXIMUM         4.17   1969
 MINIMUM            T   1934
TOTALS           0.26              1.02   -0.76     1.76
DAILY AVG.       0.01              0.03   -0.02     0.06
DAYS >= .01         3               5.3    -2.3        6
DAYS >= .10         1               2.4    -1.4        3
DAYS >= .50         0               0.5    -0.5        2
DAYS >= 1.00        0               0.1    -0.1        0
 24 HR. TOTAL    0.22   10/05 TO 10/06           10/20 TO 10/21

 TOTAL             MM   MM
TOTALS            0.0               4.0

HEATING TOTAL     231               440    -209      274
 SINCE 7/1        310               581    -271      301
COOLING TOTAL      17                 5      12       16
 SINCE 1/1        878               769     109      877

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

AVERAGE WIND SPEED              10.0

AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR           10
NUMBER OF DAYS PC             17


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

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Time to ‘fall back’ as Daylight Saving Time comes to an end

Thursday, November 3rd, 2016 7:43am MST
The United States returns to Standard Time at 2:00am Sunday as Daylight Saving Time comes to an end.

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 tonight 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 7:34am but on Sunday it will be at 6:35am. Similarly, sunset will occur at 5:53pm on Saturday but on Sunday the sun will disappear over the horizon at 4:52pm.

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 12, 2017 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.

Year DST Begins 2 a.m.
(Second Sunday in March)
DST Ends 2 a.m.
(First Sunday in November)
2016 13 March 2016 6 November 2016
2017 12 March 2017 5 November 2017
2018 11 March 2018 4 November 2018
2019 10 March 2019 3 November 2019
2020 8 March 2020 1 November 2020
2021 14 March 2021 7 November 2021
2022 13 March 2022 6 November 2022
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