National Weather Service Forecast for: Johnstown CO
Issued by: National Weather Service Denver-Boulder, CO
Updated: 3:16 pm MST Dec 17, 2025
 
Tonight

Tonight: A chance of rain before 10pm, then a chance of snow between 10pm and 11pm. Partly cloudy, with a low around 28. Breezy, with a northwest wind 16 to 21 mph, with gusts as high as 34 mph. Chance of precipitation is 30%. Little or no snow accumulation expected.
Chance
Rain/Snow and
Breezy then
Mostly Clear
and Blustery
 Thursday

Thursday: Sunny, with a high near 48. Breezy, with a northwest wind 9 to 16 mph becoming south southeast in the afternoon. Winds could gust as high as 28 mph.
Sunny and
Breezy then
Mostly Sunny

 Thursday
Night
Thursday Night: Partly cloudy, with a low around 28. South wind 5 to 8 mph.
Partly Cloudy


 Friday

Friday: Mostly sunny, with a high near 66. Breezy, with a west southwest wind 10 to 18 mph, with gusts as high as 31 mph.
Mostly Sunny
and Breezy

 Friday
Night
Friday Night: A 20 percent chance of rain after 11pm. Partly cloudy, with a low around 39. Breezy, with a west wind 11 to 17 mph, with gusts as high as 34 mph.
Slight Chance
Rain and
Breezy

 Saturday

Saturday: A 30 percent chance of rain, mainly before 11am. Partly sunny, with a high near 53.
Chance Rain


 Saturday
Night
Saturday Night: Partly cloudy, with a low around 26.
Partly Cloudy


 Sunday

Sunday: Mostly sunny, with a high near 51.
Mostly Sunny


 Sunday
Night
Sunday Night: Partly cloudy, with a low around 31.
Partly Cloudy
Lo 28 °F Hi 48 °F Lo 28 °F Hi 66 °F Lo 39 °F Hi 53 °F Lo 26 °F Hi 51 °F Lo 31 °F

Hazardous Weather Outlook
 

Tonight
 
 A chance of rain before 10pm, then a chance of snow between 10pm and 11pm. Partly cloudy, with a low around 28. Breezy, with a northwest wind 16 to 21 mph, with gusts as high as 34 mph. Chance of precipitation is 30%. Little or no snow accumulation expected.
Thursday
 
 Sunny, with a high near 48. Breezy, with a northwest wind 9 to 16 mph becoming south southeast in the afternoon. Winds could gust as high as 28 mph.
Thursday Night
 
 Partly cloudy, with a low around 28. South wind 5 to 8 mph.
Friday
 
 Mostly sunny, with a high near 66. Breezy, with a west southwest wind 10 to 18 mph, with gusts as high as 31 mph.
Friday Night
 
 A 20 percent chance of rain after 11pm. Partly cloudy, with a low around 39. Breezy, with a west wind 11 to 17 mph, with gusts as high as 34 mph.
Saturday
 
 A 30 percent chance of rain, mainly before 11am. Partly sunny, with a high near 53.
Saturday Night
 
 Partly cloudy, with a low around 26.
Sunday
 
 Mostly sunny, with a high near 51.
Sunday Night
 
 Partly cloudy, with a low around 31.
Monday
 
 Mostly sunny, with a high near 64.
Monday Night
 
 Partly cloudy, with a low around 32.
Tuesday
 
 Mostly sunny, with a high near 56.
Tuesday Night
 
 Partly cloudy, with a low around 30.
Wednesday
 
 Mostly sunny, with a high near 61.

 

Forecast from NOAA-NWS for Johnstown CO.