Harman US

St. Clair, MI Weather & Growing Conditions

Today
68°F
Chance Rain Showers
A chance of rain showers before 5pm, then a chance of showers and thunderstorms. Cloudy. High near 68, with temperatures falling to around 64 in the afternoon. Southeast wind around 8 mph. Chance of precipitation is 50%. New rainfall amounts between a tenth and quarter of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Today 68°F Chance Rain Showers 8 mph SE 50%
Tonight 56°F Chance Showers And Thunderstorms 7 mph E 84%
Sunday 68°F Rain Showers Likely 5 to 14 mph NNE 57%
Sunday Night 49°F Mostly Cloudy 7 to 14 mph NNE 1%
Monday 64°F Partly Sunny 8 to 12 mph NE 1%
Monday Night 46°F Mostly Cloudy 10 mph NE 3%
Tuesday 64°F Partly Sunny 10 to 14 mph ENE 9%
Tuesday Night 48°F Chance Rain Showers 10 to 14 mph ENE 39%
Wednesday 63°F Chance Rain Showers 14 mph E 47%
Wednesday Night 49°F Chance Rain Showers 6 to 12 mph E 39%
Thursday 65°F Slight Chance Rain Showers 9 mph ENE 24%
Thursday Night 49°F Mostly Cloudy 3 to 7 mph NE 13%
Friday 69°F Mostly Sunny 3 to 9 mph NE 8%
Friday Night 49°F Partly Cloudy 3 to 8 mph NE 7%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for St. Clair, MI

Last spring frost
May 3
First fall frost
Oct 18
Growing season
167 days
Hardiness zone
6a

Explore more for St. Clair, MI: full frost dates · planting calendar · Michigan frost dates

Climate data from the nearest NOAA station, Algonac Wwtp, Mi (10.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.