Ontonagon, MI Weather & Growing Conditions
Overnight
55°F
Rain Showers Likely
Rain showers likely. Cloudy. Low around 55, with temperatures rising to around 58 overnight. East wind around 5 mph. Chance of precipitation is 70%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 55°F | Rain Showers Likely | 5 mph E | 72% |
| Wednesday | 66°F | Rain Showers | 5 mph SE | 77% |
| Wednesday Night | 41°F | Rain Showers | 0 to 15 mph NW | 91% |
| Thursday | 46°F | Rain Showers | 15 to 20 mph N | 95% |
| Thursday Night | 30°F | Chance Rain And Snow Showers | 10 to 15 mph N | 58% |
| Friday | 44°F | Slight Chance Snow Showers then Partly Sunny | 5 to 10 mph N | 20% |
| Friday Night | 27°F | Partly Cloudy | 0 mph | 3% |
| Saturday | 47°F | Mostly Sunny | 0 to 5 mph SW | 0% |
| Saturday Night | 33°F | Partly Cloudy | 5 to 10 mph SW | 11% |
| Sunday | 49°F | Slight Chance Rain Showers | 10 to 15 mph W | 20% |
| Sunday Night | 34°F | Slight Chance Rain Showers then Partly Cloudy | 5 to 10 mph W | 15% |
| Monday | 56°F | Partly Sunny | 5 to 10 mph SW | 4% |
| Monday Night | 37°F | Partly Cloudy then Slight Chance Rain Showers | 10 mph W | 15% |
| Tuesday | 50°F | Slight Chance Rain Showers | 10 to 15 mph NW | 15% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Ontonagon, MI
Last spring frost
May 27
First fall frost
Oct 1
Growing season
127 days
Hardiness zone
5a
Explore more for Ontonagon, MI: full frost dates · planting calendar · Michigan frost dates
Climate data from the nearest NOAA station, Ontonagon 6 Se, Mi (10.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.