Which is the hottest month in Isle Royale?

The hottest time of year in Isle Royale is normally July. Expect maximum daytime temperatures to reach 24°C.

Which month has the most rain in Isle Royale?

In terms of rainfall, September is usually the wettest month in Isle Royale with 86mm on average. There are normally 13 days in September with some rain.

When is it sunniest in Isle Royale?

The sunniest time of year in Isle Royale is normally July with bright sunshine on average for 62% of daylight hours; that's 10 hours of sunshine per day.

When is the sea warmest in Isle Royale?

The sea is usually at its warmest in Isle Royale in August when the water temperature reaches 13°C.

Best time to visit Isle Royale

Q: When is the best time to visit Isle Royale?

The best time to visit Isle Royale is July based on the following average weather conditions. Maximum daytime temperature = 22 - 30°C. Daily hours of sunshine = 10 hours or more.

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Isle Royale by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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When is the best time to visit Isle Royale?

The best time to visit Isle Royale is July based on the following average weather conditions.

Maximum daytime temperature = 72 - 86°F [remove]
Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

0.5
Jan
1
Feb
1
Mar
1.5
Apr
2
May
4
Jun
5
Jul
4
Aug
1.5
Sep
0.5
Oct
0
Nov
0
Dec

Change criteria

Max Day Temperature (°F)

18
Jan
21
Feb
32
Mar
46
Apr
59
May
68
Jun
75
Jul
72
Aug
63
Sep
52
Oct
36
Nov
23
Dec

Hours of Sunshine (daily)

4
Jan
5
Feb
5
Mar
7
Apr
8
May
9
Jun
10
Jul
8
Aug
6
Sep
4
Oct
3
Nov
3
Dec

Best time to visit

Destination

Daytime temperature

Sunshine hours

Sea temperature

Monthly rainfall

Days with some rain

Heat & humidity

The weather guide for Michigan (Isle Royale) shows long term weather averages processed from data supplied by CRU (University of East Anglia) & today's weather forecast provided by meteoblue. Find out more about our data sources.

Metric (°C) | Imperial (°F)