Measurements:
°C
°F
CURRENT WEATHER
09:41
Mackinac Island
58°F
N 22 mph
Feels like: 54°F
Precip: 29%
World Resorts USA Mackinac Island Weather

7 Day Weather Forecast

09.15
tue
DAY
66°F
NE 22 mph
precip
31%
NIGHT
60°F
SE 15 mph
precip
17%
09.16
wed
DAY
58°F
W 7 mph
precip
20%
NIGHT
60°F
N 14 mph
precip
16%
09.17
thu
DAY
64°F
SE 4 mph
precip
6%
NIGHT
58°F
S 11 mph
precip
8%
09.18
fri
DAY
58°F
W 6 mph
precip
23%
NIGHT
54°F
NW 12 mph
precip
20%
09.19
sat
DAY
58°F
W 19 mph
precip
64%
NIGHT
58°F
SW 14 mph
precip
28%
09.20
sun
DAY
58°F
W 17 mph
precip
37%
NIGHT
58°F
W 19 mph
precip
21%
09.21
mon
DAY
52°F
W 22 mph
precip
23%
NIGHT
58°F
W 22 mph
precip
18%

Mackinac Island Sea Water Temperature in September, °F

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Mackinac Island was 18.5°F. The maximum and minimum values were 17.4°F and 19.6°F respectively.

Mackinac Island on the Weather Map

Best Time to Visit Mackinac Island
The most sunny months:
July 16 days
August 14 days
June 12 days
The most warm months:
August 71.7 °F
July 71.6 °F
September 64.4 °F
Warmest sea temperature:
August 69.4 °F
July 67.0 °F
September 64.1 °F
The most cold months:
February 20.1 °F
January 20.4 °F
December 28.6 °F
The most rainy months:
August 3 days
April 2 days
July 2 days
The most windy months:
November 13 mph
December 13 mph
April 11 mph
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