Copper Harbor, MI Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Copper Harbor, a community in Keweenaw County, Michigan.
Tonight
50°F
Mostly Cloudy then Slight Chance Rain Showers
A slight chance of rain showers between 2am and 4am. Mostly cloudy. Low around 50, with temperatures rising to around 53 overnight. Northwest wind 0 to 10 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.
7-day forecast for Copper Harbor
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 50°F | Mostly Cloudy then Slight Chance Rain Showers | 0 to 10 mph NW | 21% |
| Sunday | 58°F | Partly Sunny | 15 to 20 mph NE | 7% |
| Sunday Night | 47°F | Mostly Cloudy | 10 to 15 mph NE | 0% |
| Monday | 60°F | Partly Sunny | 5 to 10 mph E | 0% |
| Monday Night | 45°F | Partly Cloudy | 5 mph E | 0% |
| Tuesday | 60°F | Sunny | 5 to 10 mph E | 0% |
| Tuesday Night | 52°F | Mostly Clear | 5 mph SE | 0% |
| Wednesday | 59°F | Sunny | 5 to 10 mph SE | 0% |
| Wednesday Night | 53°F | Mostly Clear | 5 to 10 mph SE | 1% |
| Thursday | 61°F | Sunny | 5 to 10 mph SE | 2% |
| Thursday Night | 54°F | Partly Cloudy | 0 to 10 mph SE | 2% |
| Friday | 64°F | Mostly Sunny | 0 to 5 mph S | 1% |
| Friday Night | 56°F | Partly Cloudy | 0 to 5 mph S | 1% |
| Saturday | 65°F | Mostly Sunny | 5 mph S | 2% |
Forecast source: National Weather Service (api.weather.gov) for Copper Harbor (47.468, -87.870). Updated through the day.
Growing snapshot for Copper Harbor
Last spring frost
May 20
First fall frost
Oct 15
Growing season
148 days
Hardiness zone
6a
More local growing data for Copper Harbor: nearby ZIP 49918 weather · frost dates · planting calendar · Michigan frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Copper Harbor Ft Wilkins, Mi (2.6 mi from Copper Harbor). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.