Copper Harbor, MI climate
Copper Harbor has cold winters and cool summers. A typical July afternoon reaches 74°, a January night drops to 11°.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Copper Harbor feels like
Winter
Spring
Summer
Fall
Copper Harbor weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 24° | 11° | 2.3" | 6° – 26° |
| February | 26° | 11° | 1.6" | 6° – 30° |
| March | 35° | 18° | 1.6" | 16° – 38° |
| April | 46° | 29° | 2.4" | 30° – 45° |
| May | 59° | 39° | 2.9" | 44° – 54° |
| June | 69° | 48° | 2.8" | 55° – 64° |
| July | 74° | 55° | 2.9" | 58° – 69° |
| August | 73° | 55° | 2.8" | 59° – 69° |
| September | 66° | 49° | 3.2" | 52° – 64° |
| October | 52° | 38° | 3.3" | 40° – 50° |
| November | 39° | 28° | 2.4" | 26° – 41° |
| December | 29° | 18° | 2.4" | 16° – 31° |
| Year | 49° | 33° | 30.4" |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Copper Harbor
Copper Harbor gets 30 inches of rain and melted snow a year. October is the wettest month and March the driest.
About 148 frost-free days a year
In half of years the last 32° night comes by May 20 and the first one by October 15. That leaves about 148 frost-free days for gardens, shorter than 82% of U.S. towns.
Heating and cooling a home in Copper Harbor
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Copper Harbor, 98% of that work is heating and 2% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Copper Harbor and its neighbors
Copper Harbor borders 2 towns with climate data. January nights across them vary by 8.5°. Eagle Harbor has both the coldest January nights (4°) and the hottest July afternoons (74°). Copper Harbor’s January low is 11° and its July high 74°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Copper Harbor compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Copper Harbor averaged 1.6° warmer than the 1900s. The biggest change is in February (+2.9°). The shift is larger than in 75% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Copper Harbor’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 6° to 30°. June is the most reliable, staying within 9°.
Common questions about Copper Harbor’s climate
What is the coldest month in Copper Harbor?
February, with a typical high of 26° and a low of 11°.
What is the hottest month in Copper Harbor?
July, with a typical high of 74° and a low of 55°. About 1 days a year reach 90°.
When is the first frost in Copper Harbor?
In half of years the first 32° night comes by October 15, and the last spring frost by May 20.
What is the rainiest month in Copper Harbor?
October, with 3.3 inches of rain and melted snow. The year totals 30 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Copper Harbor itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Copper Harbor Ft Wilkins, MI (1 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.