Isle Royale National Park

Weather History, Monthly Averages & Best Time to Visit

MIMidwest800 ft

Look Up a Specific Date

Searching weather history for Isle Royale

Best Time to Visit

RecommendedMay - October

Late spring through early fall offers the best conditions.

AvoidNovember - March (cold temperatures, some facilities closed)

Tip: Fall foliage in late September and October can be spectacular.

Monthly Climate Averages

Historical temperature and precipitation averages for Houghton, MI, based on 55+ years of weather data.

Warmest MonthJulyAvg High: 76°F / Low: 56°F
Coldest MonthJanuaryAvg High: 22°F / Low: 10°F
Jan
22°/ 10°
💧 4.0"
❄️ 3.0"
Feb
25°/ 10°
💧 3.2"
❄️ 2.2"
Mar
34°/ 18°
💧 4.1"
❄️ 2.0"
Apr
46°/ 29°
💧 4.8"
❄️ 1.7"
May
62°/ 41°
💧 6.3"
❄️ 1.5"
Jun
71°/ 50°
💧 7.0"
Jul
76°/ 56°
💧 7.0"
Aug
75°/ 56°
💧 7.0"
Sep
66°/ 48°
💧 7.0"
❄️ 1.1"
Oct
53°/ 38°
💧 5.1"
❄️ 1.2"
Nov
39°/ 27°
💧 4.0"
❄️ 1.8"
Dec
28°/ 16°
💧 3.8"
❄️ 2.9"

Temperatures in Fahrenheit. Precipitation and snowfall in inches.

Data from Houghton, MI. Expect ~3°F cooler at elevation.

Official NPS Websitenps.gov/isro