St. Clair, MN Weather & Growing Conditions
Tonight
59°F
Patchy Fog
Patchy fog and a chance of showers and thunderstorms before 4am, then a chance of showers and thunderstorms. Cloudy, with a low around 59. East wind 10 to 15 mph. Chance of precipitation is 70%. New rainfall amounts between three quarters and one inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 59°F | Patchy Fog | 10 to 15 mph E | 66% |
| Saturday | 66°F | Chance Showers And Thunderstorms then Slight Chance T-storms | 10 mph NE | 27% |
| Saturday Night | 55°F | Slight Chance Drizzle then Mostly Cloudy | 10 mph NNE | 19% |
| Sunday | 66°F | Mostly Cloudy | 10 to 15 mph NE | 4% |
| Sunday Night | 50°F | Mostly Cloudy | 10 mph ENE | 14% |
| Monday | 61°F | Chance Rain Showers | 10 mph ENE | 37% |
| Monday Night | 46°F | Chance Rain Showers then Mostly Cloudy | 5 to 10 mph ENE | 37% |
| Tuesday | 62°F | Partly Sunny | 5 to 10 mph E | 6% |
| Tuesday Night | 44°F | Partly Cloudy | 5 mph ESE | 0% |
| Wednesday | 66°F | Sunny | 5 mph SE | 0% |
| Wednesday Night | 49°F | Partly Cloudy | 0 to 5 mph SSE | 10% |
| Thursday | 68°F | Mostly Sunny | 0 to 5 mph SSE | 14% |
| Thursday Night | 52°F | Partly Cloudy | 0 to 5 mph SSE | 6% |
| Friday | 69°F | Mostly Sunny | 5 mph SE | 7% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Clair, MN
Last spring frost
Apr 30
First fall frost
Oct 9
Growing season
161 days
Hardiness zone
5a
Explore more for St. Clair, MN: full frost dates · planting calendar · Minnesota frost dates
Climate data from the nearest NOAA station, Mankato, Mn (9.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.