National Weather Service Forecast for: Lewistown MT
Issued by: National Weather Service Great Falls, MT
Updated: 9:27 pm MST Dec 16, 2025
 
Tonight

Tonight: Mostly cloudy, with a low around 37. Breezy, with a south southwest wind 14 to 22 mph, with gusts as high as 33 mph.
Mostly Cloudy
then Mostly
Cloudy and
Breezy
 Wednesday

Wednesday: Rain likely, possibly mixing with snow after 11am, then gradually ending. Patchy blowing dust after 11am. Mostly cloudy during the morning, then sunny during the afternoon, with a temperature rising to near 48 by 10am, then falling to around 33 during the remainder of the day. Windy, with a west wind 25 to 30 mph increasing to 38 to 43 mph in the afternoon. Winds could gust as high as 65 mph. Chance of precipitation is 60%. Little or no snow accumulation expected.
Windy.
Rain/Snow
Likely then
Patchy
Blowing Dust
 Wednesday
Night
Wednesday Night: Patchy blowing dust before 10pm. Mostly cloudy, with a low around 18. Windy, with a west northwest wind 28 to 38 mph decreasing to 18 to 28 mph after midnight. Winds could gust as high as 60 mph.
Patchy
Blowing Dust
and Windy

 Thursday

Thursday: Increasing clouds, with a high near 43. South southwest wind 7 to 13 mph, with gusts as high as 22 mph.
Increasing
Clouds

 Thursday
Night
Thursday Night: A slight chance of snow, mixing with rain after 8pm, then gradually ending. Mostly cloudy, with a low around 31. West southwest wind 11 to 20 mph, with gusts as high as 33 mph. Chance of precipitation is 20%.
Slight Chance
Rain/Snow
then Mostly
Cloudy
 Friday

Friday: A chance of rain and snow before 11am, then a chance of snow. Partly sunny, with a high near 48. West northwest wind 17 to 20 mph, with gusts as high as 32 mph. Chance of precipitation is 40%. New snow accumulation of less than a half inch possible.
Chance
Rain/Snow
then Chance
Snow
 Friday
Night
Friday Night: A 40 percent chance of snow. Mostly cloudy, with a low around 19. West wind 9 to 11 mph, with gusts as high as 22 mph. New snow accumulation of less than one inch possible.
Chance Snow


 Saturday

Saturday: A slight chance of snow before 11am. Mostly sunny, with a high near 37. West wind 8 to 13 mph, with gusts as high as 22 mph.
Slight Chance
Snow then
Mostly Sunny

 Saturday
Night
Saturday Night: Partly cloudy, with a low around 21.
Partly Cloudy
Lo 37 °F Hi 48 °F⇓ Lo 18 °F Hi 43 °F Lo 31 °F Hi 48 °F Lo 19 °F Hi 37 °F Lo 21 °F

High Wind Warning
 

Tonight
 
 Mostly cloudy, with a low around 37. Breezy, with a south southwest wind 14 to 22 mph, with gusts as high as 33 mph.
Wednesday
 
 Rain likely, possibly mixing with snow after 11am, then gradually ending. Patchy blowing dust after 11am. Mostly cloudy during the morning, then sunny during the afternoon, with a temperature rising to near 48 by 10am, then falling to around 33 during the remainder of the day. Windy, with a west wind 25 to 30 mph increasing to 38 to 43 mph in the afternoon. Winds could gust as high as 65 mph. Chance of precipitation is 60%. Little or no snow accumulation expected.
Wednesday Night
 
 Patchy blowing dust before 10pm. Mostly cloudy, with a low around 18. Windy, with a west northwest wind 28 to 38 mph decreasing to 18 to 28 mph after midnight. Winds could gust as high as 60 mph.
Thursday
 
 Increasing clouds, with a high near 43. South southwest wind 7 to 13 mph, with gusts as high as 22 mph.
Thursday Night
 
 A slight chance of snow, mixing with rain after 8pm, then gradually ending. Mostly cloudy, with a low around 31. West southwest wind 11 to 20 mph, with gusts as high as 33 mph. Chance of precipitation is 20%.
Friday
 
 A chance of rain and snow before 11am, then a chance of snow. Partly sunny, with a high near 48. West northwest wind 17 to 20 mph, with gusts as high as 32 mph. Chance of precipitation is 40%. New snow accumulation of less than a half inch possible.
Friday Night
 
 A 40 percent chance of snow. Mostly cloudy, with a low around 19. West wind 9 to 11 mph, with gusts as high as 22 mph. New snow accumulation of less than one inch possible.
Saturday
 
 A slight chance of snow before 11am. Mostly sunny, with a high near 37. West wind 8 to 13 mph, with gusts as high as 22 mph.
Saturday Night
 
 Partly cloudy, with a low around 21.
Sunday
 
 Partly sunny, with a high near 41.
Sunday Night
 
 A slight chance of rain and snow. Mostly cloudy, with a low around 25.
Monday
 
 A slight chance of rain and snow. Mostly cloudy, with a high near 45.
Monday Night
 
 Mostly cloudy, with a low around 26.
Tuesday
 
 Partly sunny, with a high near 46.

 

Forecast from NOAA-NWS for Lewistown MT.