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The Regional Temperatures and Precipitation Product for the State of Montana (RTPMT) will be discontinued on May 6, 2026.

Hazardous Weather Conditions

Winter Weather Advisory in effect from April 22, 06:00 PM MDT until April 23, 06:00 PM MDT

Current conditions at

USCRN SITE NEAR ST. MARY 1SSW (MRYM8)

Lat: 48.74111°NLon: 113.43306°WElev: 4550.0ft.

37°F

3°C

Humidity	68%
Wind Speed	NA 0 MPH
Barometer	NA
Dewpoint	27°F (-3°C)
Visibility	NA
Last update	22 Apr 04:10 AM MDT

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Extended Forecast for

St Mary MT

Winter Weather Advisory April 22, 06:00pm until April 23, 06:00pm

Click here for hazard details and duration

Winter Weather Advisory

Today
High: 59 °F
Chance Rain
then Showers
Tonight
Low: 24 °F
Rain/Snow
then Snow
Thursday
High: 35 °F
Snow Likely
Thursday Night
Low: 19 °F
Snow Likely
Friday
High: 30 °F
Chance Snow
Friday Night
Low: 19 °F
Chance Snow
Saturday
High: 34 °F
Chance Snow
Saturday Night
Low: 18 °F
Mostly Cloudy
Sunday
High: 37 °F
Slight Chance
Snow

Detailed Forecast

Today

A chance of rain and thunderstorms, then showers and possibly a thunderstorm after 2pm. High near 59. Light and variable wind becoming north northwest 5 to 10 mph in the morning. Winds could gust as high as 23 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.

Tonight

Rain and snow, becoming all snow after midnight. Low around 24. North wind around 11 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New snow accumulation of 1 to 2 inches possible.

Thursday

Snow likely, mainly before noon. Mostly cloudy, with a high near 35. North wind 11 to 13 mph, with gusts as high as 26 mph. Chance of precipitation is 70%. New snow accumulation of 1 to 3 inches possible.

Thursday Night

Snow likely, mainly before midnight. Mostly cloudy, with a low around 19. North wind around 9 mph, with gusts as high as 21 mph. Chance of precipitation is 60%. New snow accumulation of around an inch possible.

Friday

A 50 percent chance of snow. Mostly cloudy, with a high near 30. North wind 8 to 11 mph, with gusts as high as 24 mph. New snow accumulation of less than one inch possible.

Friday Night

A 30 percent chance of snow. Mostly cloudy, with a low around 19. North wind 5 to 9 mph, with gusts as high as 20 mph. Little or no snow accumulation expected.

Saturday

A 30 percent chance of snow. Mostly cloudy, with a high near 34. North northeast wind 3 to 7 mph. Little or no snow accumulation expected.

Saturday Night

Mostly cloudy, with a low around 18. Northeast wind 5 to 7 mph becoming calm in the evening.

Sunday

A slight chance of snow. Partly sunny, with a high near 37.

Sunday Night

Mostly cloudy, with a low around 20.

Monday

A slight chance of snow. Mostly sunny, with a high near 48.

Monday Night

Partly cloudy, with a low around 30.