active National Weather Service watches, warnings and advisories
Checking the National Weather Service for active alerts covering Thornton…
Thornton weather in numbers
measured normals and 10 years of recorded weather
Thornton swings 71°F across the year, from 87°F highs in July to 16°F lows in January, and May is usually the wettest month in a year that brings about 17 in of precipitation. Over 10 years of recorded weather it averages 118 days a year at 77°F or above, 63 of them at 86°F or above, 146 frost nights, and rain on 79 days.
Warmest month
July
87°F average high
Coldest month
January
16°F average low
Wettest month
May
17 in a year
Comfortable
2 months
April and October
Residents
133,000
share this forecast
Most accurate here
European
82/100 CheckWeather Score
Warm days
118 days
a year at 77°F or above
Frost nights
146 nights
a year below 32°F
Rain days
79 days
a year with 0.04 in or more
Day counts are from the ERA5 reanalysis for Thornton’s grid square, 2016 to 2025, counted the same way for every city so the numbers compare. A reanalysis square is an area, not a weather station, so it is good for counting days and not for a single day’s record.
The weather map: all three models at once
NWS, American, European side by side around Thornton and nearby towns.Live rain radar →
Loading the three model maps…
Thornton hourly forecast: next 14 hours
consensus of the three models
Rain in the next 24 hours, model by model
each model's own hourly precipitation, side by side
Loading the three models…
Thornton 10-day forecast, out to 14 days
where the models agree, and where they split
Today
Light drizzle
58°46°
models agree
Tomorrow
Light drizzle
61°42°
±5°
Mon
Light drizzle
59°46°
models agree
Tue
Cloudy
66°41°
models agree
Wed
Cloudy
66°43°
models agree
Thu
Partly cloudy
69°44°
±9°
Fri
Cloudy
69°45°
±11°
Sat
Partly cloudy
67°47°
±7°
Sun
Light snow
60°45°
models agree
Mon
Light snow
62°42°
±4°
Tue
Clear
68°41°
models agree
Wed
Clear
61°45°
±21°
Thu
Cloudy
59°42°
±25°
Thornton, Colorado (CO) is at its warmest in Jul (average highs near 87°F) and coldest in Jan (lows around 16°F), with roughly 17 in of precipitation across the year. Below, compare what NWS, American, European forecast for Thornton right now, and see exactly where they disagree.
average daytime high and overnight low across a typical year (1991-2020)
Jan
37°
16°
Feb
42°
16°
Mar
53°
27°
Apr
61°
33°
May
69°
44°
Jun
81°
55°
Jul
87°
59°
Aug
85°
59°
Sep
79°
49°
Oct
64°
36°
Nov
49°
26°
Dec
41°
19°
Source: 1991-2020 averages, ERA5 for this place adjusted with NASA POWER.
How Thornton's weather has changed since 1995
30 years of daily data, 1995-2024, shown as change
+0.8°F
Around Thornton, the difference between 1995-2004 and 2015-2024 is +0.8°F, within the normal swing from year to year.
1995each stripe is one year2024
cooler than averagearound averagewarmer than average
Days above 95°F
5 more days a year
2015-2024 against 1995-2004. Within the normal year-to-year swing
Frost nights
1 fewer night a year
2015-2024 against 1995-2004, below 32°F. Within the normal year-to-year swing
Average wind
no clear change
2015-2024 against 1995-2004. Within the normal year-to-year swing
Bars: each year against the area's 30-year average. Dashed lines: the average of the first and the last ten years.
See the numbers year by year
Year
Temp vs average
Days >95°F vs avg
Frost nights vs avg
Wind vs avg
1995
−1.3°F
−4
−3
−4%
1996
−1.1°F
−9
+6
+7%
1997
−1.8°F
−9
+12
−2%
1998
−0.7°F
−5
−2
−7%
1999
−0.2°F
−9
−2
+4%
2000
+0.5°F
+2
+4
−2%
2001
+0.9°F
−0
−2
−4%
2002
+0.2°F
+15
+9
+1%
2003
+0.7°F
+8
−12
−2%
2004
−0.2°F
−8
−13
−2%
2005
+0.7°F
+3
−8
+1%
2006
+0.5°F
−0
−2
+7%
2007
+0.3°F
+6
−10
+4%
2008
−0.9°F
+2
+17
+7%
2009
−1.8°F
−12
+4
+4%
2010
−0.4°F
−7
+13
−4%
2011
−0.7°F
−0
+14
+4%
2012
+2.5°F
+12
−26
+1%
2013
−1.5°F
−1
+18
−2%
2014
−1.1°F
−8
+5
+4%
2015
+0.2°F
−11
−21
−4%
2016
+1.1°F
−3
−18
−2%
2017
+0.9°F
−3
−18
+1%
2018
+0.5°F
+1
+17
−2%
2019
−1.3°F
+1
+19
−4%
2020
+0.9°F
+12
+6
+1%
2021
+1.1°F
+7
−1
−2%
2022
+0.2°F
+10
+11
+4%
2023
−0.4°F
+3
+2
−4%
2024
+2.3°F
+14
−8
−2%
Source: NASA POWER daily data from the MERRA-2 reanalysis, 1995-2024. Each value describes a grid square of about 50 km around Thornton, not a weather station, and a square that takes in sea or a large lake runs milder than the city itself. That is why this section shows change against the square's own 30-year average rather than counts you could compare with a local station. Rain and snow are left out because their long-term record in this dataset is not consistent over time. "Within the normal year-to-year swing" means the change is smaller than the usual differences between single years.
Which forecast is most accurate in Thornton?
CheckWeather Score, graded against the weather that actually happened
Provider
CheckWeather-score
Temp
Wind
Rain
Run by
European ★ Best
82
/100rank #1
93±0.7°F
90±3.2 mph
6581% hit
ECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American
80
/100rank #2
90±1.0°F
93±2.2 mph
5877% hit
NOAA / NCEP (United States)College Park, Maryland, USA
The accuracy above is the measured record. This is your opinion: which forecast service do you trust most in United States? Give each 1 to 5 stars.
NWSNational Blend (NBM)
Loading ratings…
AmericanNOAA GFS
Loading ratings…
EuropeanECMWF
Loading ratings…
One vote per service. Anonymous: we store no personal data, only a one-way hash of your connection for a day to stop double votes.
Where the models disagree
temperature and rain, judged separately
Day
Temperature
Rain
Today
±2°57° to 59°
±12%9% to 21% chance
Tomorrow
±5°59° to 64°
±10%56% to 66% chance
Mon
±1°59° to 60°
±13%53% to 66% chance
Tue
±2°65° to 67°
±1%0% to 1% chance
Wed
±3°65° to 68°
±1%1% to 2% chance
The models often agree on temperature and still split on rain, and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.
Sunrise and sunset in Thornton
today, local time
Sunrise
07:20
Sunset
18:07
Daylight
10h 47m
Common questions
What's the weather in Thornton today?
Saturday, October 24: NWS, the American and the European model agree on a high near 58° in Thornton today. Tomorrow: light drizzle, around 61°, with a 66% chance of rain. The forecast on this page refreshes live.
Will it rain in Thornton today or tomorrow?
Rain is likely in Thornton on Sunday, October 25: every model gives at least 56% (NWS 66%, American 66%, European 56%). On Saturday, October 24 the highest chance of rain from any model is 21%. The hourly strip and the model-by-model rain panel above update live.
Which forecast is most accurate for Thornton?
Over the last 30 days, the European model has been the most accurate for Thornton (CheckWeather Score 82/100), ahead of the American at 80. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Thornton?
July is typically the warmest month in Thornton, with average highs around 87°F.
How cold does Thornton get?
The coldest month in Thornton is January, when overnight lows average about 16°F.
How much rain does Thornton get?
Thornton sees roughly 17 in of precipitation a year, with May usually the wettest month.
Is Thornton getting warmer?
Not clearly. In NASA's reanalysis for the area around Thornton, the difference between 1995-2004 and 2015-2024 is 0.8°F, within the normal swing from year to year.
CheckWeather.io on iPhoneFree. No ads, no account.
