National Weather Service Forecast for: Lewistown MT
Issued by: National Weather Service Great Falls, MT
Updated: 3:27 am MST Dec 22, 2025
 
Today

Today: A 40 percent chance of rain between 9am and 11am.  Cloudy, then gradually becoming mostly sunny, with a high near 46. Southwest wind 6 to 10 mph becoming west northwest in the afternoon. Winds could gust as high as 21 mph.
Chance Rain
then Partly
Sunny

Tonight

Tonight: Mostly cloudy, with a low around 28. Light and variable wind becoming east southeast around 6 mph in the evening.
Mostly Cloudy


Tuesday

Tuesday: Mostly cloudy, with a high near 49. South wind around 6 mph.
Mostly Cloudy


Tuesday
Night
Tuesday Night: Mostly cloudy, with a low around 33. South wind around 6 mph.
Mostly Cloudy


Wednesday

Wednesday: Partly sunny, with a high near 55. South wind 6 to 10 mph, with gusts as high as 18 mph.
Partly Sunny


Wednesday
Night
Wednesday Night: A chance of rain between 11pm and 2am, then a chance of freezing rain after 2am.  Cloudy, with a low around 27. West wind 5 to 8 mph.  Chance of precipitation is 50%.
Chance Rain
then Chance
Rain/Freezing
Rain
Christmas
Day
Christmas Day: A chance of freezing rain before 10am, then a chance of rain.  Mostly cloudy, with a high near 41. Light and variable wind becoming north northeast around 6 mph in the afternoon.  Chance of precipitation is 40%.
Chance
Rain/Freezing
Rain then
Slight Chance
Rain
Thursday
Night
Thursday Night: A slight chance of freezing rain before 11pm, then a slight chance of rain after 5am.  Mostly cloudy, with a low around 28. South wind around 7 mph.
Slight Chance
Freezing Rain
then Slight
Chance Rain
Friday

Friday: A slight chance of rain and snow before 8am, then a slight chance of snow between 8am and 11am.  Mostly cloudy, with a high near 44.
Slight Chance
Rain/Snow
then Mostly
Cloudy
Hi 46 °F Lo 28 °F Hi 49 °F Lo 33 °F Hi 55 °F Lo 27 °F Hi 41 °F Lo 28 °F Hi 44 °F

 

Today
 
A 40 percent chance of rain between 9am and 11am. Cloudy, then gradually becoming mostly sunny, with a high near 46. Southwest wind 6 to 10 mph becoming west northwest in the afternoon. Winds could gust as high as 21 mph.
Tonight
 
Mostly cloudy, with a low around 28. Light and variable wind becoming east southeast around 6 mph in the evening.
Tuesday
 
Mostly cloudy, with a high near 49. South wind around 6 mph.
Tuesday Night
 
Mostly cloudy, with a low around 33. South wind around 6 mph.
Wednesday
 
Partly sunny, with a high near 55. South wind 6 to 10 mph, with gusts as high as 18 mph.
Wednesday Night
 
A chance of rain between 11pm and 2am, then a chance of freezing rain after 2am. Cloudy, with a low around 27. West wind 5 to 8 mph. Chance of precipitation is 50%.
Christmas Day
 
A chance of freezing rain before 10am, then a chance of rain. Mostly cloudy, with a high near 41. Light and variable wind becoming north northeast around 6 mph in the afternoon. Chance of precipitation is 40%.
Thursday Night
 
A slight chance of freezing rain before 11pm, then a slight chance of rain after 5am. Mostly cloudy, with a low around 28. South wind around 7 mph.
Friday
 
A slight chance of rain and snow before 8am, then a slight chance of snow between 8am and 11am. Mostly cloudy, with a high near 44.
Friday Night
 
Mostly cloudy, with a low around 19.
Saturday
 
Partly sunny, with a high near 37.
Saturday Night
 
Partly cloudy, with a low around 24.
Sunday
 
Partly sunny, with a high near 46.

 

Forecast from NOAA-NWS for Lewistown MT.