Thornton, Colorado, USA
UpdatedSun, 25-Jun-2017 11:20pm MDT 


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Another warm and breezy day Tuesday

Tuesday, February 7th, 2017 5:13am MDT

Thornton will enjoy another very mild day today with temperatures approaching 20 degrees above normal. There will however also be a healthy dose of wind to go along with it.

We start out the day with mostly sunny skies and will see a little bit of increase in cloud cover as the day progresses. Temperatures will once again warm quickly and we can expect a high in the low to mid-60s. Winds will continue throughout the day with gusts around 30 mph being possible.

A cold front will backdoor its way into the state later but we don’t expect it to come far enough west to impact us much. We do see just the slightest chance for a few drops of rain after 4:00pm into the late evening. Overnight tonight partly to mostly clear skies will be above and temperatures will drop to around 40 degrees.

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Hawaii’s Kilauea Volcano Firehose Lava Flow Finally Cut Off

Monday, February 6th, 2017 8:22am MDT

The firehose lava flow that had been spilling out of a seaside cliff on Hawaii’s Kilauea volcano since New Year’s Eve finally stopped Thursday after a portion of the cliff collapsed, according to reports. Hawaii Volcano Observatory geologists were at the site observing a large crack in a section of the cliff and were able to… » Click here to read the rest of Hawaii’s Kilauea Volcano Firehose Lava Flow Finally Cut Off

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January 2017 weather recap: Colder, wetter than normal weather for second month in a row

Monday, February 6th, 2017 6:52am MDT

The month of December brought colder and wetter than normal conditions to Thornton and in January we continued that trend with more of the same and our first month of the season with above average snowfall.

January started out warmer than normal but on the third that changed with a system that sent temperatures plummeting for five days.  From the 3rd to the 7th the mercury failed to even climb above freezing and we saw three overnight lows dip to zero or below.  The period also brought 7.4 inches over a three day period from the 3rd to the 5th.

Once that system moved out, we returned to warmer and dry conditions for four days then saw light snow on the 11th and 12th followed by colder temperatures through the 16th.  The 16th also brought our last measurable snow for the month.

The last half of the month was relatively uneventful and the final three days saw highs climb over the 60 degree mark.

Thornton saw an average temperature in January of 29.5 degrees.  This is a good ways below the long term Denver average for the month of 30.7 degrees.  Out at DIA where Denver’s official measurements are kept, it was slightly warmer with an average of 30.0 degrees.

Temperatures in our part of town ranged from a high of 66 degrees on January 31 down to a low of 9.4 degrees below zero on the morning of the 6th.  Denver saw its warmest reading of 63 degrees on the 30th and its coldest of 7 below zero on the morning of the 6th.

In terms of precipitation, the Mile High City averages 0.41 inches in January.  Both Thornton and Denver came in wetter than that with 0.77 inches and 0.54 inches of liquid precipitation at those locations respectively.

Thornton welcomed a respectable 10.0 inches of snowfall during the month.  Out at the airport, their total lagged ours with a reading of 6.3 inches.  On average Denver receives 7.0 inches during the month.

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

Thornton, Colorado's January 2017 temperature summary.

Thornton, Colorado’s January 2017 temperature summary.

Thornton, Colorado's January 2017 precipitation summary.

Thornton, Colorado’s January 2017 precipitation summary.

From the National Weather Service:



                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
 HIGH              76   01/27/1888
 LOW              -29   01/09/1875
HIGHEST            63   01/30        76     -13       65  01/30
LOWEST             -7   01/06       -29      22        5  01/10
AVG. MAXIMUM     42.3              44.0    -1.7     43.5
AVG. MINIMUM     17.7              17.4     0.3     20.1
MEAN             30.0              30.7    -0.7     31.8
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      8               5.5     2.5        3
DAYS MIN <= 32     30              29.4     0.6       30
DAYS MIN <= 0       2               1.7     0.3        0

 MAXIMUM         2.35   1883
 MINIMUM         0.01   1933
TOTALS           0.54              0.41    0.13     0.50
DAILY AVG.       0.02              0.01    0.01     0.02
DAYS >= .01         3               4.1    -1.1        5
DAYS >= .10         3               0.9     2.1        3
DAYS >= .50         0               0.0     0.0        0
DAYS >= 1.00        0               0.0     0.0        0
 24 HR. TOTAL    0.34   01/04 TO 01/05
TOTALS            6.3               7.0
                 24.3              1992

HEATING TOTAL    1075              1063      12     1021
 SINCE 7/1       3117              3531    -414     3208
COOLING TOTAL       0                 0       0        0
 SINCE 1/1          0                 0       0        0

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

AVERAGE WIND SPEED              9.0

AVERAGE SKY COVER           0.60
NUMBER OF DAYS FAIR            5
NUMBER OF DAYS PC             20


THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       0
LIGHT RAIN                0     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                1     SNOW                       2
LIGHT SNOW                9     SLEET                      0
FOG                      11     FOG W/VIS <= 1/4 MILE      2
HAZE                      7

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Thornton’s workweek starts with mild and breezy conditions

Monday, February 6th, 2017 5:01am MDT

The warm weather we enjoyed over the weekend will continue into today. We do unfortunately expect another good dose of wind to go along with the mild conditions.

We start out the day with mostly sunny skies and should see similar sky conditions throughout the day. Temperatures will warm quickly this morning and work their way toward a high around 60 degrees.

Downslope winds will increase this morning and by late morning be gusting to over 20 mph. They will continue into the evening before settling down.

Overnight tonight look for partly cloudy skies and lows in the mid-30s.

Have a great Monday!

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

Sunday, February 5th, 2017 4:55am MDT
This Week In Denver Weather History

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

February is generally a relatively calm weather month however just like any other month in Denver, it can and does see its extremes. In looking back at the Denver weather history calendar for the week, there are many entries for damaging wind, some heavy snowfall and extreme cold.

From the National Weather Service:


In 1985…a cold front on the 29th produced a protracted cold spell as arctic air remained entrenched across metro Denver. While the only daily temperature record set was a low maximum reading of 2 degrees on February 3rd…minimum temperatures plunged well below zero on 9 consecutive days. The coldest readings were 15 degrees below zero on January 31st and 14 degrees below zero on February 5th.


In 1963…warm weather that began with the strong Chinook winds on the 31st and 1st continued through the 8th. Maximum temperatures through the period ranged from 52 degrees on the 2nd to 76 degrees on the 5th…which was a new record high for that date.


In 1899…a protracted cold spell lasted almost two weeks. Low temperatures plunged below zero on all days but February 9th with a reading of 6 degrees. The coldest low temperature of 22 degrees below zero on February 6th was a record low for the date. Low temperatures of 20 degrees below zero occurred on both February 11th and 12th… But only the 11th remains as the record minimum for the date. High temperature of only 5 degrees below zero on February 11th was a record low maximum for the date. High temperatures climbed to only zero degrees on both February 2nd and 3rd…but were not records. Intermittent light snow or flurries fell during the period. The most snowfall…2.0 inches…occurred on February 2nd.


In 1985…the most bitter cold spell of the winter season brought sub-zero temperatures to metro Denver. Daily low temperature records were broken at Denver. The usual cold weather problems struck including stalled vehicles…jammed traffic lights…and frozen water and sewer lines. At Stapleton International Airport…the high temperature was only 2 degrees above zero on the 1st…setting a record low maximum for the date. Low temperatures reached 13 below zero on the 1st…12 below on the third…and 14 below on the 5th.


In 1989…one of the century’s worst doses of winter weather ravaged the entire state. Bitterly frigid weather moved into metro Denver on the 1st as snow buried many sections of the state. In metro Denver where 3 to 6 inches of snow fell…blowing snow and resultant poor visibilities caused a 46-car pile-up on I-25 in the middle of the city on the 4th. During the period…2 to 3 hour delays were common at Stapleton International Airport where snowfall from the storm totaled 4.3 inches and northeast winds gusted to 30 mph on the 1st. Intense cold accompanied the storm. Temperatures in Denver stayed below zero continuously for the best part of 3 days (3rd…4th…5th)…for a total of 69 hours. This is the fourth longest sub-zero period on record. Wind chill temperatures reached 50 degrees below zero. The mercury dipped to 24 degrees below zero on the 5th…setting a record for the date. This was the city’s coldest temperature in over 26 years. Low temperatures dipped below zero on 8 consecutive days (2nd-9th). High temperature of 9 degrees below zero on the 4th was a record low maximum for the date…as was the high of 5 degrees on the 5th. Extensive damage occurred when pipes and water lines froze and broke. Thousands of cars failed to start. On the 3rd…a 57-year-old woman died of hypothermia in an Arvada park. Eighteen high school students were treated for hypothermia after a 2-hour ride through Jefferson County in an unheated bus. At least 2 cases of frostbite were reported; there were undoubtedly many more.


In 1883…a protracted cold period occurred when low temperatures dipped below zero for 9 consecutive days. Low temperatures ranged from 22 degrees below zero on the 4th to 2 degrees below zero on the 1st and 6th. High temperatures ranged from 10 below zero on the 3rd to 23 on the 9th. Several temperature records were set that still stand today. Record lows of 18 below and 22 below zero occurred on the 3rd and 4th. Record low maximum readings of 2 below and 10 below zero occurred on the 2nd and 3rd. The high of only 10 below zero on the 3rd is the coldest maximum temperature ever recorded in Denver.


In 1982…a cold surge of arctic air brought light snow and sub-zero temperatures to metro Denver. Temperatures plunged to 6 below zero at midnight on the 3rd and never warmed above zero on the 4th as snow flurries continued. High temperature on the 4th of 1 below zero was a record low maximum. The temperature dipped to a record low of 15 below zero on the 5th.


In 1932…wind gusts estimated at 70 mph occurred in Boulder. A 60 mph wind gust was recorded to the east of Boulder in Valmont. Damage was minor.

In 1959…heavy snowfall totaled 5.8 inches at Stapleton Airport where northwest winds gusted to 30 mph on the 4th.

In 2001…high winds developed for a brief time overnight. Winds gusted to 75 mph atop the Gamow Tower on the University of Colorado campus in Boulder. Northwest winds gusting to 37 mph warmed the temperature to a high of 57 degrees at Denver International Airport.


In 1986…10 inches of snow fell in Boulder…in the foothill town of Wondervu southwest of Boulder…and at Evergreen west of Denver. Snowfall totaled 2.4 inches at Stapleton International Airport…where north winds gusted to 20 mph on the 6th.


In 1885…west winds were sustained to 42 mph in the city near daybreak.

In 1902…northwest winds sustained to 48 mph with gusts to 53 mph warmed the temperature to a high of 53 degrees.

In 2006…high winds developed briefly along the foothills… Extending from Golden to near Boulder. Peak wind reports included 92 mph at the National Wind Technology Center on Rocky Flats with a gust to 84 mph in Golden. North winds gusted to 43 mph at Denver International Airport.

In 2011…heavy snow fell in the foothills of Douglas… Jefferson and Park counties. Storm totals included: 19 inches…3 miles southwest of Conifer; 17.5 inches…4 miles south-southeast of Pinecliffe; 14 inches…5 miles east-southeast of aspen park; 12.5 inches…7 miles southwest of Boulder and at Genesee; 12 inches at Strontia Springs dam…10.5 inches at Roxborough state park; and 10 inches…3 miles east-southeast of tiny town. In the western and southern Denver suburbs and palmer divide…storm totals included: 9 inches near Louviers and 3 miles south-southeast of Morrison; 8 inches at Ralston Reservoir…7 inches in Lakewood…6.5 inches…2 miles southeast of Highlands Ranch and 6 inches in Englewood. Snowfall totaled 1.2 inches at Denver International Airport.


In 2003…heavy snow fell in the foothills. Snowfall totals included: 17 inches at Genesee; 16 inches at Lookout Mountain; 11 inches at Chief Hosa near Indian Hills…and 7 miles southwest of Boulder; 10.5 inches atop gold hill; and 10 inches at Intercanyon and near Conifer. Only 2.2 inches of snowfall were measured in the city at the site of the former Stapleton International Airport.


In 1978…the 5th marked the start of a record 7 consecutive days of dense fog at Stapleton International Airport. The heavy fog reduced the visibility to 1/4 mile or less for a period of time on each of these days. Light snow and/or freezing drizzle occurred on most days. Fog reducing visibility to less than 7 miles was recorded at Stapleton International Airport on 11 consecutive days through the 15th. During the period 5-14…the cold thick fog deposited heavy rime ice up to 5 inches thick on power lines and poles over a wide area of eastern Colorado…causing a major electrical power outage disaster.

» Click here to read the rest of February 5 to February 11: This week in Denver weather history

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Thornton’s February weather preview: Winter’s grip begins to loosen

Sunday, February 5th, 2017 4:40am MDT

Thornton and Denver, Colorado February Weather Preview.February in Colorado typically brings to an end an extended period when average temperatures are at their lowest. Winter begins to loosen its grip and temperatures get warmer but precipitation is not a particularly common event during the month.

Thus far our snow season is extraordinarily well in terms of snowpack with all basins in Colorado having well above normal levels.  At lower elevations however, the snow season has been pretty poor  due to a slow start.  February is only our sixth snowiest month so we may not see much snowfall for the balance of the month.

Temperatures however do usually see a nice rebound during the month. Average high temperatures climb from an average of 44 degrees at the start to 50 degrees by the end of February.

For the complete February preview including a look at historical averages and extremes as well as a look at what long range forecasts are predicting, click here. 

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A chilly Friday to be followed by a warm weekend in Thornton

Friday, February 3rd, 2017 5:14am MDT

Lingering cold air from yesterday’s weather system will keep things cool Friday. That however will soon be replaced with much warmer temperatures Saturday and Sunday, albeit with some wind tomorrow.

For today we are seeing some patchy fog early. Once that dissipates we will see a good bit of cloud cover but that will gradually easy throughout the day leading to mostly sunny skies this afternoon. Temperatures today will top out around 40 degrees and overall conditions will be calm and dry. Overnight tonight temperatures will dip below freezing initially but then actually warm up as Chinook winds then warm things up late.

Saturday brings about significantly warmer temperatures but unfortunately will also bring along the wind. Look for sunny to mostly sunny skies through the day tomorrow and dry conditions. Temperatures will top out close to the 60 degree mark. The wind is expected to get started in the pre-dawn hours and continue through the day into the evening with gusts to 30 mph or so in the afternoon. Winds will ease after dark tomorrow and temperatures will drop to near freezing.

Super Bowl Sunday looks to be overall the most pleasant day of the three-day period. The winds should be pretty much done and there will be a healthy dose of sun above. Look for high temperatures in the upper 50s.

Previewing the first half of next week, dry mild conditions should be the rule.

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Following a slick start to Thursday, temps will remain cold, some sun arrives

Thursday, February 2nd, 2017 5:38am MDT

We are waking to some very slippery roads courtesy of freezing drizzle that arrived late yesterday. Once the sun comes up precipitation will gradually end over the morning and we should see a bit of sun later.

First up, it should go without saying that road conditions are tricky today. Side streets are especially slippery with main roads and highways a bit better but still hazardous. Allow yourself plenty of time for your commute this morning, slow down and leave lots of room between you and the car in front.

Intermittent drizzle along with a few snowflakes will be possible through mid-morning and then we should see the precipitation come to an end. Breaks in the clouds can be expected about that same time leading to partly sunny skies in the afternoon. Temperatures today will remain below normal with a high of only 37 degrees expected.

This evening may bring some light snow / flurries but no accumulation is expected. Overnight temperatures will be dropping to the upper teens.

Have a great day today, stay warm and more importantly, stay safe!

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Colder, cloudier Wednesday, overnight to bring freezing drizzle and fog

Wednesday, February 1st, 2017 5:12am MDT

A cold front pushed through last night with some very gusty winds for a period. Now that the system is here, we will see colder, unsettled weather for the next 48 hours or so.

We start out the day with mostly cloudy skies. A bit of easing in the cloud cover should happen around mid-day before increasing again by late afternoon into the evening. Temperatures are going to be much colder than we had been enjoying recently with highs today only around 40 degrees.

This evening and overnight moisture will be increasing moisture leading to what appears will be a freezing drizzle / rain event, something we don’t get very often. Some precipitation will be possible after about 5:00pm with the best chances coming after 8:00pm into tomorrow morning.

There isn’t a lot of moisture but enough that the freezing precipitation could create hazardous road conditions overnight and tomorrow morning so be aware.

Temperatures will be dropping to around 20 degrees tonight. In addition to the freezing drizzle, tomorrow may see some fog in areas.

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January 2017 top shots: Monthly photo slideshow

Tuesday, January 31st, 2017 8:09am MDT
Geese walk across a frozen Barr Lake with the snow-capped Rocky Mountains in the background. (Shawn Jones)

Geese walk across a frozen Barr Lake with the snow-capped Rocky Mountains in the background. (Shawn Jones)

As one of our coldest months, January can be a good month to hibernate inside and avoid the outdoors.  But, like any month in Colorado, photo opportunities abound as our monthly slideshow demonstrates.

Snow is not normally dominant in the month but when it does fall, it can create a beautiful blanket of white.  Throw in the amazing sunrises and sunsets we receive in the middle of winter as well as wildlife and a host of other subjects and the imagery can be quite beautiful and stunning.

  • Slideshow updated January 31, 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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