Ontonagon, MI Weather & Growing Conditions
Today
77°F
Chance Rain Showers then Partly Sunny
A chance of rain showers before 10am. Partly sunny, with a high near 77. West wind around 10 mph, with gusts as high as 25 mph. Chance of precipitation is 30%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 77°F | Chance Rain Showers then Partly Sunny | 10 mph W | 33% |
| Tonight | 56°F | Partly Cloudy | 0 to 10 mph W | 1% |
| Wednesday | 79°F | Sunny | 0 to 5 mph W | 0% |
| Wednesday Night | 59°F | Mostly Clear | 0 to 5 mph S | 0% |
| Thursday | 89°F | Sunny | 5 to 10 mph SW | 2% |
| Thursday Night | 67°F | Mostly Clear | 5 to 10 mph SW | 5% |
| Friday | 89°F | Sunny then Slight Chance Showers And Thunderstorms | 5 to 10 mph SW | 18% |
| Friday Night | 63°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 5 mph SW | 38% |
| Saturday | 81°F | Slight Chance Showers And Thunderstorms | 5 mph W | 24% |
| Saturday Night | 61°F | Chance Showers And Thunderstorms | 0 to 5 mph W | 45% |
| Sunday | 80°F | Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms | 0 to 5 mph W | 38% |
| Sunday Night | 59°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph W | 24% |
| Monday | 79°F | Partly Sunny then Slight Chance Rain Showers | 0 to 5 mph W | 15% |
| Monday Night | 58°F | Slight Chance Rain Showers | 0 to 5 mph W | 18% |
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 Aug 4, 2026.