Isle Royale weather by month

Check out Isle Royale weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature
Rainfall
Sunshine & daylight
UV levels & humidity

Temperature in Isle Royale (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	-8	-6	0	8	15	20	24	22	17	11	2	-5
Min temperature (night-time)	-18	-17	-11	-3	3	8	12	11	7	2	-5	-14
Heat & Humidity	0	0	0	0	0	0	0	0	0	0	0	0
Sea temperature	2	2	2	2	3	3	6	13	12	8	5	4

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & Daylight in Isle Royale

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Daily hours of sunshine	4	5	5	7	8	9	10	8	6	4	3	3
Daily hours of daylight	9	10	12	14	15	16	16	14	13	11	9	8
UV Index (Maximum)	1	1	3	4	6	7	7	6	5	2	1	1

Rainfall in Isle Royale

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	10	8	9	8	10	13	11	12	13	11	9	11
Average monthly rainfall (mm)	63	38	48	44	68	81	77	84	86	69	59	59

More about Isle Royale

Isle Royale by month

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

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The climate guide for Michigan (Isle Royale) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Isle Royale?

Isle Royale has a cold climate with warm summers and some rainfall in all months.

Isle Royale weather in January

Expect daytime maximum temperatures of -8°C in Isle Royale, Michigan in January based on long-term weather averages. There are 4 hours of sunshine per day on average with 10 days with some rainfall and typically 63 mm of rainfall in the month, which might fall as snow.

-8
-8°C max day temperature
4
4 hours of sunshine per day
10
10 days with some rainfall
-18
-18°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
63
63 mm of monthly rainfall
1
1 (Low) UV index
2
2°C sea temperature

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Isle Royale weather in February

Expect daytime maximum temperatures of -6°C in Isle Royale, Michigan in February based on long-term weather averages. There are 5 hours of sunshine per day on average, which might fall as snow.

-6
-6°C max day temperature
5
5 hours of sunshine per day
8
8 days with some rainfall
-17
-17°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
38
38 mm of monthly rainfall
1
1 (Low) UV index
2
2°C sea temperature

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Isle Royale weather in March

Expect daytime maximum temperatures of 0°C in Isle Royale, Michigan in March based on long-term weather averages. There are 5 hours of sunshine per day on average with typically 48 mm of rainfall in the month, which might fall as snow.

0
0°C max day temperature
5
5 hours of sunshine per day
9
9 days with some rainfall
-11
-11°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
48
48 mm of monthly rainfall
3
3 (Moderate) UV index
2
2°C sea temperature

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Isle Royale weather in April

Expect daytime maximum temperatures of 8°C in Isle Royale, Michigan in April based on long-term weather averages. There are 7 hours of sunshine per day on average with typically 44 mm of rainfall in the month.

8
8°C max day temperature
7
7 hours of sunshine per day
8
8 days with some rainfall
-3
-3°C min night temperature
14
14 hours of daylight per day
0
No heat & humidity
44
44 mm of monthly rainfall
4
4 (Moderate) UV index
2
2°C sea temperature

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Isle Royale weather in May

Expect daytime maximum temperatures of 15°C in Isle Royale, Michigan in May based on long-term weather averages. There are 8 hours of sunshine per day on average with 10 days with some rainfall and typically 68 mm of rainfall in the month.

15
15°C max day temperature
8
8 hours of sunshine per day
10
10 days with some rainfall
3
3°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
68
68 mm of monthly rainfall
6
6 (High) UV index
3
3°C sea temperature

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Isle Royale weather in June

Expect daytime maximum temperatures of 20°C in Isle Royale, Michigan in June based on long-term weather averages. There are 9 hours of sunshine per day on average with 13 days with some rainfall and typically 81 mm of rainfall in the month.

20
20°C max day temperature
9
9 hours of sunshine per day
13
13 days with some rainfall
8
8°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
81
81 mm of monthly rainfall
7
7 (High) UV index
3
3°C sea temperature

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Isle Royale weather in July

Expect daytime maximum temperatures of 24°C in Isle Royale, Michigan in July based on long-term weather averages. There are 10 hours of sunshine per day on average with 11 days with some rainfall and typically 77 mm of rainfall in the month.

24
24°C max day temperature
10
10 hours of sunshine per day
11
11 days with some rainfall
12
12°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
77
77 mm of monthly rainfall
7
7 (High) UV index
6
6°C sea temperature

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Isle Royale weather in August

Expect daytime maximum temperatures of 22°C in Isle Royale, Michigan in August based on long-term weather averages. There are 8 hours of sunshine per day on average with 12 days with some rainfall and typically 84 mm of rainfall in the month.

22
22°C max day temperature
8
8 hours of sunshine per day
12
12 days with some rainfall
11
11°C min night temperature
14
14 hours of daylight per day
0
No heat & humidity
84
84 mm of monthly rainfall
6
6 (High) UV index
13
13°C sea temperature

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Isle Royale weather in September

Expect daytime maximum temperatures of 17°C in Isle Royale, Michigan in September based on long-term weather averages. There are 6 hours of sunshine per day on average with 13 days with some rainfall and typically 86 mm of rainfall in the month.

17
17°C max day temperature
6
6 hours of sunshine per day
13
13 days with some rainfall
7
7°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
86
86 mm of monthly rainfall
5
5 (Moderate) UV index
12
12°C sea temperature

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Isle Royale weather in October

Expect daytime maximum temperatures of 11°C in Isle Royale, Michigan in October based on long-term weather averages. There are 4 hours of sunshine per day on average with 11 days with some rainfall and typically 69 mm of rainfall in the month.

11
11°C max day temperature
4
4 hours of sunshine per day
11
11 days with some rainfall
2
2°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
69
69 mm of monthly rainfall
2
2 (Low) UV index
8
8°C sea temperature

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Isle Royale weather in November

Expect daytime maximum temperatures of 2°C in Isle Royale, Michigan in November based on long-term weather averages. There are 3 hours of sunshine per day on average with typically 59 mm of rainfall in the month, which might fall as snow.

2
2°C max day temperature
3
3 hours of sunshine per day
9
9 days with some rainfall
-5
-5°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
59
59 mm of monthly rainfall
1
1 (Low) UV index
5
5°C sea temperature

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Isle Royale weather in December

Expect daytime maximum temperatures of -5°C in Isle Royale, Michigan in December based on long-term weather averages. There are 3 hours of sunshine per day on average with 11 days with some rainfall and typically 59 mm of rainfall in the month, which might fall as snow.

-5
-5°C max day temperature
3
3 hours of sunshine per day
11
11 days with some rainfall
-14
-14°C min night temperature
8
8 hours of daylight per day
0
No heat & humidity
59
59 mm of monthly rainfall
1
1 (Low) UV index
4
4°C sea temperature

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