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CheckWeather USLongmont
Forecast confidence: Medium · models disagree by 7°F

Longmont weather

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Drizzle,rain likely tomorrow

NWS, the American and the European model put Longmont's high today between 80° and 87°, a 7° split. Tomorrow looks light rain around 75°, with a 99% chance of rain.

83°59°
75°56°
72°52°
74°51°
78°52°
78°54°
Todaysplit ±7°Tomorrowsplit ±6°Sundaysplit ±7°Mondaysplit ±9°Tuesdaysplit ±8°Wednesdaymodels agree
NWSNational Blend (NBM)
72°
Partly cloudy
Feels 73° · Wind 5 mph · Humidity 55%
AmericanNOAA GFS
80°
Overcast
Feels 77° · Wind 2 mph · Humidity 26%
EuropeanECMWF
78°
Light drizzle
Feels 79° · Wind 1 mph · Humidity 35%

Latest for Longmont: NWS (National Blend (NBM)): 72° Partly cloudy · American (NOAA GFS): 80° Overcast · European (ECMWF): 78° Light drizzle.

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Longmont weather alerts and warnings

active National Weather Service watches, warnings and advisories

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Longmont weather in numbers

from 30 years of measured normals

Longmont swings 72°F across the year, from 86°F highs in July to 14°F lows in January, and June is usually the wettest month in a year that brings about 21 in of precipitation.

Warmest month
July
86°F average high
Coldest month
January
14°F average low
Wettest month
June
21 in a year
Below freezing
5 months
January, February, March, November and December
Comfortable
3 months
April, May and October
Residents
92,000
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The weather map: all three models at once

NWS, American, European side by side around Longmont and nearby towns.Live rain radar →
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Longmont 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

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Longmont 10-day forecast, out to 14 days

where the models agree, and where they split
Today
Drizzle
83° 59°
±7°
Tomorrow
Light rain
75° 56°
±6°
Sun
Light drizzle
72° 52°
±7°
Mon
Light drizzle
74° 51°
±9°
Tue
Mostly clear
78° 52°
±8°
Wed
Light drizzle
78° 54°
models agree
Thu
Partly cloudy
79° 54°
models agree
Fri
Light drizzle
81° 55°
±13°
Sat
Light drizzle
81° 57°
±13°
Sun
Mostly clear
80° 53°
models agree
Mon
Light drizzle
75° 52°
±4°
Tue
Cloudy
81° 51°
±16°
Wed
Cloudy
82° 54°
models agree
Thu
Cloudy
85° 56°
models agree

Longmont, Colorado (CO) is at its warmest in Jul (average highs near 86°F) and coldest in Jan (lows around 14°F), with roughly 21 in of precipitation across the year. Below, compare what NWS, American, European forecast for Longmont right now, and see exactly where they disagree.

We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in United States before you trust any single number.

Longmont climate by month

average daytime high and overnight low across a typical year
Jan
34°
14°
Feb
42°
15°
Mar
48°
23°
Apr
61°
33°
May
70°
43°
Jun
80°
54°
Jul
86°
56°
Aug
85°
57°
Sep
80°
49°
Oct
67°
40°
Nov
48°
25°
Dec
44°
24°

Which forecast is most accurate in Longmont?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
78
/100rank #1
87±1.3°F93±2.3 mph5877% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
58
/100rank #2
74±2.6°F90±3.0 mph1855% hitNOAA / NCEP (United States)College Park, Maryland, USA

The CheckWeather Score blends temperature, wind and rain accuracy, each measured against ERA5 (the recorded weather) over the last 30 days across 1999 cities. Lower error means a higher score. See which forecast model is most accurate in United States, how we measure forecast accuracy, or which model each weather app uses.

What do you think of the forecasts?

your vote counts

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)
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AmericanNOAA GFS
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EuropeanECMWF
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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
DayTemperatureRain
Today±7°80° to 87°±65%25% to 90% chance
Tomorrow±6°73° to 79°±64%35% to 99% chance
Sun±7°69° to 76°±51%37% to 88% chance
Mon±9°70° to 79°±12%16% to 28% chance
Tue±8°75° to 83°±4%10% to 14% 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 Longmont

today, local time
Sunrise
06:44
Sunset
19:03
Daylight
12h 19m

Common questions

What's the weather in Longmont today?
On this page we show what NWS, American, European each forecast for Longmont today, side by side and updated live. When all three agree the forecast is reliable; when they split, we flag it so you know the day is genuinely less certain.
Will it rain in Longmont today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Longmont and flag the days where the models disagree on whether showers actually arrive, which is exactly when a single app can catch you out.
Which forecast is most accurate for Longmont?
Over the last 30 days, the European model has been the most accurate for Longmont (CheckWeather Score 78/100), ahead of the American at 58. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Longmont?
July is typically the warmest month in Longmont, with average highs around 86°F.
How cold does Longmont get?
The coldest month in Longmont is January, when overnight lows average about 14°F.
How much rain does Longmont get?
Longmont sees roughly 21 in of precipitation a year, with June usually the wettest month.

Nearby

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