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 in Isle Royale (°F)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
18°F maximum daytime temperature in January in Isle Royale18
21°F maximum daytime temperature in February in Isle Royale21
32°F maximum daytime temperature in March in Isle Royale32
46°F maximum daytime temperature in April in Isle Royale46
59°F maximum daytime temperature in May in Isle Royale59
68°F maximum daytime temperature in June in Isle Royale68
75°F maximum daytime temperature in July in Isle Royale75
72°F maximum daytime temperature in August in Isle Royale72
63°F maximum daytime temperature in September in Isle Royale63
52°F maximum daytime temperature in October in Isle Royale52
36°F maximum daytime temperature in November in Isle Royale36
23°F maximum daytime temperature in December in Isle Royale23
Min temperature (night-time)
-0°F minimum night-time temperature in January in Isle Royale-0
1°F minimum night-time temperature in February in Isle Royale1
12°F minimum night-time temperature in March in Isle Royale12
27°F minimum night-time temperature in April in Isle Royale27
37°F minimum night-time temperature in May in Isle Royale37
46°F minimum night-time temperature in June in Isle Royale46
54°F minimum night-time temperature in July in Isle Royale54
52°F minimum night-time temperature in August in Isle Royale52
45°F minimum night-time temperature in September in Isle Royale45
36°F minimum night-time temperature in October in Isle Royale36
23°F minimum night-time temperature in November in Isle Royale23
7°F minimum night-time temperature in December in Isle Royale7
Heat & Humidity
No heat & humidity in January in Isle Royale0
No heat & humidity in February in Isle Royale0
No heat & humidity in March in Isle Royale0
No heat & humidity in April in Isle Royale0
No heat & humidity in May in Isle Royale0
No heat & humidity in June in Isle Royale0
No heat & humidity in July in Isle Royale0
No heat & humidity in August in Isle Royale0
No heat & humidity in September in Isle Royale0
No heat & humidity in October in Isle Royale0
No heat & humidity in November in Isle Royale0
No heat & humidity in December in Isle Royale0
Sea temperature
36°F sea temperature in January in Isle Royale36
36°F sea temperature in February in Isle Royale36
36°F sea temperature in March in Isle Royale36
36°F sea temperature in April in Isle Royale36
37°F sea temperature in May in Isle Royale37
37°F sea temperature in June in Isle Royale37
43°F sea temperature in July in Isle Royale43
55°F sea temperature in August in Isle Royale55
54°F sea temperature in September in Isle Royale54
46°F sea temperature in October in Isle Royale46
41°F sea temperature in November in Isle Royale41
39°F sea temperature in December in Isle Royale39

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
Daily hours of daylight
9 hours of daylight per day in January in Isle Royale9
10 hours of daylight per day in February in Isle Royale10
12 hours of daylight per day in March in Isle Royale12
14 hours of daylight per day in April in Isle Royale14
15 hours of daylight per day in May in Isle Royale15
16 hours of daylight per day in June in Isle Royale16
16 hours of daylight per day in July in Isle Royale16
14 hours of daylight per day in August in Isle Royale14
13 hours of daylight per day in September in Isle Royale13
11 hours of daylight per day in October in Isle Royale11
9 hours of daylight per day in November in Isle Royale9
8 hours of daylight per day in December in Isle Royale8
UV Index (Maximum)
UV (maximum) index 1 (Low) in January in Isle Royale1
UV (maximum) index 1 (Low) in February in Isle Royale1
UV (maximum) index 3 (Moderate) in March in Isle Royale3
UV (maximum) index 4 (Moderate) in April in Isle Royale4
UV (maximum) index 6 (High) in May in Isle Royale6
UV (maximum) index 7 (High) in June in Isle Royale7
UV (maximum) index 7 (High) in July in Isle Royale7
UV (maximum) index 6 (High) in August in Isle Royale6
UV (maximum) index 5 (Moderate) in September in Isle Royale5
UV (maximum) index 2 (Low) in October in Isle Royale2
UV (maximum) index 1 (Low) in November in Isle Royale1
UV (maximum) index 1 (Low) in December in Isle Royale1

Rainfall in Isle Royale

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of days with some rain
10 days with some rainfall in January in Isle Royale10
8 days with some rainfall in February in Isle Royale8
9 days with some rainfall in March in Isle Royale9
8 days with some rainfall in April in Isle Royale8
10 days with some rainfall in May in Isle Royale10
13 days with some rainfall in June in Isle Royale13
11 days with some rainfall in July in Isle Royale11
12 days with some rainfall in August in Isle Royale12
13 days with some rainfall in September in Isle Royale13
11 days with some rainfall in October in Isle Royale11
9 days with some rainfall in November in Isle Royale9
11 days with some rainfall in December in Isle Royale11
Average monthly rainfall (inches)
2.5 inches monthly rainfall in January in Isle Royale2.5
1.5 inches monthly rainfall in February in Isle Royale1.5
1.9 inches monthly rainfall in March in Isle Royale1.9
1.7 inches monthly rainfall in April in Isle Royale1.7
2.7 inches monthly rainfall in May in Isle Royale2.7
3.2 inches monthly rainfall in June in Isle Royale3.2
3.0 inches monthly rainfall in July in Isle Royale3.0
3.3 inches monthly rainfall in August in Isle Royale3.3
3.4 inches monthly rainfall in September in Isle Royale3.4
2.7 inches monthly rainfall in October in Isle Royale2.7
2.3 inches monthly rainfall in November in Isle Royale2.3
2.3 inches monthly rainfall in December in Isle Royale2.3

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 18°F 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 2.5 inches of rainfall in the month, which might fall as snow.

  • 18°F maximum daytime temperature in January in Isle Royale18
    18°F max day temperature
  • 4 hours of sunshine per day
  • 10 days with some rainfall in January in Isle Royale10
    10 days with some rainfall
  • -0°F minimum night-time temperature in January in Isle Royale-0
    -0°F min night temperature
  • 9 hours of daylight per day in January in Isle Royale9
    9 hours of daylight per day
  • No heat & humidity in January in Isle Royale0
    No heat & humidity
  • 2.5 inches monthly rainfall in January in Isle Royale2.5
    2.5 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in January in Isle Royale1
    1 (Low) UV index
  • 36°F sea temperature in January in Isle Royale36
    36°F sea temperature

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Isle Royale weather in February

Expect daytime maximum temperatures of 21°F 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.

  • 21°F maximum daytime temperature in February in Isle Royale21
    21°F max day temperature
  • 5 hours of sunshine per day
  • 8 days with some rainfall in February in Isle Royale8
    8 days with some rainfall
  • 1°F minimum night-time temperature in February in Isle Royale1
    1°F min night temperature
  • 10 hours of daylight per day in February in Isle Royale10
    10 hours of daylight per day
  • No heat & humidity in February in Isle Royale0
    No heat & humidity
  • 1.5 inches monthly rainfall in February in Isle Royale1.5
    1.5 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in February in Isle Royale1
    1 (Low) UV index
  • 36°F sea temperature in February in Isle Royale36
    36°F sea temperature

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Isle Royale weather in March

Expect daytime maximum temperatures of 32°F in Isle Royale, Michigan in March based on long-term weather averages. There are 5 hours of sunshine per day on average with typically 1.9 inches of rainfall in the month, which might fall as snow.

  • 32°F maximum daytime temperature in March in Isle Royale32
    32°F max day temperature
  • 5 hours of sunshine per day
  • 9 days with some rainfall in March in Isle Royale9
    9 days with some rainfall
  • 12°F minimum night-time temperature in March in Isle Royale12
    12°F min night temperature
  • 12 hours of daylight per day in March in Isle Royale12
    12 hours of daylight per day
  • No heat & humidity in March in Isle Royale0
    No heat & humidity
  • 1.9 inches monthly rainfall in March in Isle Royale1.9
    1.9 inches of monthly rainfall
  • UV (maximum) index 3 (Moderate) in March in Isle Royale3
    3 (Moderate) UV index
  • 36°F sea temperature in March in Isle Royale36
    36°F sea temperature

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Isle Royale weather in April

Expect daytime maximum temperatures of 46°F in Isle Royale, Michigan in April based on long-term weather averages. There are 7 hours of sunshine per day on average with typically 1.7 inches of rainfall in the month.

  • 46°F maximum daytime temperature in April in Isle Royale46
    46°F max day temperature
  • 7 hours of sunshine per day
  • 8 days with some rainfall in April in Isle Royale8
    8 days with some rainfall
  • 27°F minimum night-time temperature in April in Isle Royale27
    27°F min night temperature
  • 14 hours of daylight per day in April in Isle Royale14
    14 hours of daylight per day
  • No heat & humidity in April in Isle Royale0
    No heat & humidity
  • 1.7 inches monthly rainfall in April in Isle Royale1.7
    1.7 inches of monthly rainfall
  • UV (maximum) index 4 (Moderate) in April in Isle Royale4
    4 (Moderate) UV index
  • 36°F sea temperature in April in Isle Royale36
    36°F sea temperature

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Isle Royale weather in May

Expect daytime maximum temperatures of 59°F 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 2.7 inches of rainfall in the month.

  • 59°F maximum daytime temperature in May in Isle Royale59
    59°F max day temperature
  • 8 hours of sunshine per day
  • 10 days with some rainfall in May in Isle Royale10
    10 days with some rainfall
  • 37°F minimum night-time temperature in May in Isle Royale37
    37°F min night temperature
  • 15 hours of daylight per day in May in Isle Royale15
    15 hours of daylight per day
  • No heat & humidity in May in Isle Royale0
    No heat & humidity
  • 2.7 inches monthly rainfall in May in Isle Royale2.7
    2.7 inches of monthly rainfall
  • UV (maximum) index 6 (High) in May in Isle Royale6
    6 (High) UV index
  • 37°F sea temperature in May in Isle Royale37
    37°F sea temperature

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Isle Royale weather in June

Expect daytime maximum temperatures of 68°F 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 3.2 inches of rainfall in the month.

  • 68°F maximum daytime temperature in June in Isle Royale68
    68°F max day temperature
  • 9 hours of sunshine per day
  • 13 days with some rainfall in June in Isle Royale13
    13 days with some rainfall
  • 46°F minimum night-time temperature in June in Isle Royale46
    46°F min night temperature
  • 16 hours of daylight per day in June in Isle Royale16
    16 hours of daylight per day
  • No heat & humidity in June in Isle Royale0
    No heat & humidity
  • 3.2 inches monthly rainfall in June in Isle Royale3.2
    3.2 inches of monthly rainfall
  • UV (maximum) index 7 (High) in June in Isle Royale7
    7 (High) UV index
  • 37°F sea temperature in June in Isle Royale37
    37°F sea temperature

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Isle Royale weather in July

Expect daytime maximum temperatures of 75°F 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 3.0 inches of rainfall in the month.

  • 75°F maximum daytime temperature in July in Isle Royale75
    75°F max day temperature
  • 10 hours of sunshine per day
  • 11 days with some rainfall in July in Isle Royale11
    11 days with some rainfall
  • 54°F minimum night-time temperature in July in Isle Royale54
    54°F min night temperature
  • 16 hours of daylight per day in July in Isle Royale16
    16 hours of daylight per day
  • No heat & humidity in July in Isle Royale0
    No heat & humidity
  • 3.0 inches monthly rainfall in July in Isle Royale3.0
    3.0 inches of monthly rainfall
  • UV (maximum) index 7 (High) in July in Isle Royale7
    7 (High) UV index
  • 43°F sea temperature in July in Isle Royale43
    43°F sea temperature

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Isle Royale weather in August

Expect daytime maximum temperatures of 72°F 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 3.3 inches of rainfall in the month.

  • 72°F maximum daytime temperature in August in Isle Royale72
    72°F max day temperature
  • 8 hours of sunshine per day
  • 12 days with some rainfall in August in Isle Royale12
    12 days with some rainfall
  • 52°F minimum night-time temperature in August in Isle Royale52
    52°F min night temperature
  • 14 hours of daylight per day in August in Isle Royale14
    14 hours of daylight per day
  • No heat & humidity in August in Isle Royale0
    No heat & humidity
  • 3.3 inches monthly rainfall in August in Isle Royale3.3
    3.3 inches of monthly rainfall
  • UV (maximum) index 6 (High) in August in Isle Royale6
    6 (High) UV index
  • 55°F sea temperature in August in Isle Royale55
    55°F sea temperature

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Isle Royale weather in September

Expect daytime maximum temperatures of 63°F 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 3.4 inches of rainfall in the month.

  • 63°F maximum daytime temperature in September in Isle Royale63
    63°F max day temperature
  • 6 hours of sunshine per day
  • 13 days with some rainfall in September in Isle Royale13
    13 days with some rainfall
  • 45°F minimum night-time temperature in September in Isle Royale45
    45°F min night temperature
  • 13 hours of daylight per day in September in Isle Royale13
    13 hours of daylight per day
  • No heat & humidity in September in Isle Royale0
    No heat & humidity
  • 3.4 inches monthly rainfall in September in Isle Royale3.4
    3.4 inches of monthly rainfall
  • UV (maximum) index 5 (Moderate) in September in Isle Royale5
    5 (Moderate) UV index
  • 54°F sea temperature in September in Isle Royale54
    54°F sea temperature

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Isle Royale weather in October

Expect daytime maximum temperatures of 52°F 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 2.7 inches of rainfall in the month.

  • 52°F maximum daytime temperature in October in Isle Royale52
    52°F max day temperature
  • 4 hours of sunshine per day
  • 11 days with some rainfall in October in Isle Royale11
    11 days with some rainfall
  • 36°F minimum night-time temperature in October in Isle Royale36
    36°F min night temperature
  • 11 hours of daylight per day in October in Isle Royale11
    11 hours of daylight per day
  • No heat & humidity in October in Isle Royale0
    No heat & humidity
  • 2.7 inches monthly rainfall in October in Isle Royale2.7
    2.7 inches of monthly rainfall
  • UV (maximum) index 2 (Low) in October in Isle Royale2
    2 (Low) UV index
  • 46°F sea temperature in October in Isle Royale46
    46°F sea temperature

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Isle Royale weather in November

Expect daytime maximum temperatures of 36°F in Isle Royale, Michigan in November based on long-term weather averages. There are 3 hours of sunshine per day on average with typically 2.3 inches of rainfall in the month, which might fall as snow.

  • 36°F maximum daytime temperature in November in Isle Royale36
    36°F max day temperature
  • 3 hours of sunshine per day
  • 9 days with some rainfall in November in Isle Royale9
    9 days with some rainfall
  • 23°F minimum night-time temperature in November in Isle Royale23
    23°F min night temperature
  • 9 hours of daylight per day in November in Isle Royale9
    9 hours of daylight per day
  • No heat & humidity in November in Isle Royale0
    No heat & humidity
  • 2.3 inches monthly rainfall in November in Isle Royale2.3
    2.3 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in November in Isle Royale1
    1 (Low) UV index
  • 41°F sea temperature in November in Isle Royale41
    41°F sea temperature

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Isle Royale weather in December

Expect daytime maximum temperatures of 23°F 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 2.3 inches of rainfall in the month, which might fall as snow.

  • 23°F maximum daytime temperature in December in Isle Royale23
    23°F max day temperature
  • 3 hours of sunshine per day
  • 11 days with some rainfall in December in Isle Royale11
    11 days with some rainfall
  • 7°F minimum night-time temperature in December in Isle Royale7
    7°F min night temperature
  • 8 hours of daylight per day in December in Isle Royale8
    8 hours of daylight per day
  • No heat & humidity in December in Isle Royale0
    No heat & humidity
  • 2.3 inches monthly rainfall in December in Isle Royale2.3
    2.3 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in December in Isle Royale1
    1 (Low) UV index
  • 39°F sea temperature in December in Isle Royale39
    39°F sea temperature

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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.

Metric (°C)  |  Imperial (°F)

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More about the USA

Compare Isle Royale with the UK

Below the Isle Royale chart shows average maximum daytime temperature for Isle Royale, Michigan, USA and the UK (London).

Maximum daytime temperature (°F)

Isle Royale, Michigan, USA
UK (London)
45
45
32
50
46
55
59
63
68
68
75
72
72
72
63
66
52
59
36
50
46
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
18
21
23

Metric (°C)  |  Imperial (°F)

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