Petersburg, MI Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Petersburg, a city in Monroe County, Michigan.
Overnight
62°F
Slight Chance Light Rain
A slight chance of rain after 5am. Mostly cloudy. Low around 62, with temperatures rising to around 64 overnight. South wind around 12 mph, with gusts as high as 25 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Petersburg
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 62°F | Slight Chance Light Rain | 12 mph S | 18% |
| Wednesday | 68°F | Light Rain | 13 to 16 mph S | 96% |
| Wednesday Night | 50°F | Light Rain Likely then Mostly Cloudy | 8 to 13 mph SW | 62% |
| Thursday | 60°F | Mostly Cloudy | 10 to 16 mph SW | 8% |
| Thursday Night | 43°F | Mostly Cloudy then Chance Light Rain | 3 to 9 mph W | 37% |
| Friday | 54°F | Chance Light Rain | 3 to 9 mph NW | 48% |
| Friday Night | 35°F | Chance Light Rain | 8 mph NW | 43% |
| Saturday | 52°F | Slight Chance Light Rain then Partly Sunny | 10 mph NW | 16% |
| Saturday Night | 31°F | Partly Cloudy | 3 to 7 mph WNW | 2% |
| Sunday | 56°F | Mostly Sunny | 6 to 13 mph W | 6% |
| Sunday Night | 32°F | Partly Cloudy | 5 to 9 mph W | 6% |
| Monday | 59°F | Mostly Sunny | 5 to 10 mph WSW | 2% |
| Monday Night | 36°F | Partly Cloudy | 8 mph SW | 1% |
| Tuesday | 61°F | Mostly Sunny | 8 to 12 mph W | 3% |
Forecast source: National Weather Service (api.weather.gov) for Petersburg (41.900, -83.714). Updated through the day.
Growing snapshot for Petersburg
Last spring frost
Apr 27
First fall frost
Oct 21
Growing season
176 days
Hardiness zone
6a
More local growing data for Petersburg: nearby ZIP 49270 weather · frost dates · planting calendar · Michigan frost dates
Nearby towns & communities
Carleton
Detroit Beach
Dundee
Estral Beach
Ida
Lambertville
Luna Pier
Maybee
Milan
Monroe
South Monroe
South Rockwood
Stony Point
Temperance
West Monroe
Woodland Beach
Climate data from the nearest NOAA station, Dundee, Mi (5.9 mi from Petersburg). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.