Ontonagon, MI Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Ontonagon, a village in Ontonagon County, Michigan.
Today
74°F
Mostly Sunny
Mostly sunny, with a high near 74. West wind 10 to 15 mph, with gusts as high as 25 mph.
7-day forecast for Ontonagon
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 74°F | Mostly Sunny | 10 to 15 mph W | 14% |
| Tonight | 58°F | Partly Cloudy | 5 to 10 mph W | 1% |
| Wednesday | 76°F | Sunny | 5 mph W | 0% |
| Wednesday Night | 61°F | Mostly Clear | 5 to 10 mph S | 0% |
| Thursday | 84°F | Sunny | 5 to 10 mph SW | 2% |
| Thursday Night | 67°F | Mostly Clear | 5 to 10 mph SW | 4% |
| Friday | 83°F | Sunny then Slight Chance Showers And Thunderstorms | 5 to 10 mph SW | 17% |
| Friday Night | 63°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 5 mph SW | 37% |
| Saturday | 74°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 5 to 10 mph W | 24% |
| Saturday Night | 61°F | Chance Showers And Thunderstorms | 5 mph W | 43% |
| Sunday | 73°F | Chance Showers And Thunderstorms | 5 to 10 mph W | 35% |
| Sunday Night | 60°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 5 mph W | 24% |
| Monday | 72°F | Partly Sunny then Slight Chance Showers And Thunderstorms | 5 to 10 mph W | 15% |
| Monday Night | 59°F | Slight Chance Showers And Thunderstorms | 5 mph NW | 17% |
Forecast source: National Weather Service (api.weather.gov) for Ontonagon (46.866, -89.312). Updated through the day.
Growing snapshot for Ontonagon
Last spring frost
May 27
First fall frost
Oct 1
Growing season
127 days
Hardiness zone
5a
More local growing data for Ontonagon: nearby ZIP 49953 weather · frost dates · planting calendar · Michigan frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Ontonagon 6 Se, Mi (10.9 mi from Ontonagon). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.