World Resorts USA Mackinac Island Weather

Mackinac Island sea water temperature

Current sea water temperature:
+32.2°F
Minimum sea water temperature in March: 36.7°F
Maximum sea water temperature in March: 32.0°F
Average sea water temperature in March: 33.3°F

Sea water temperature for the last 10 days:

March 18 32.2°F March 13 33.4°F
March 17 32.2°F March 12 34.0°F
March 16 32.2°F March 11 34.7°F
March 15 32.0°F March 10 35.1°F
March 14 32.5°F March 9 35.2°F

When is the warmest sea in Mackinac Island?

Based on the data about daily sea water temperature for the last three years the warmest sea in Mackinac Island was noticed in August, July and September.

Monthly Sea Temperatures in Mackinac Island, °F

Sea water temperature in August, °F

Show year:
2025
2024
2023

The average sea water temperature in August of 2025 was 69.4°F. The highest and lowest sea temperatures during the month were 72.3°F and 65.3°F.

Sea water temperature in July, °F

Show year:
2025
2024
2023

The average sea water temperature in July of 2025 was 65.8°F. The highest and lowest sea temperatures during the month were 70.7°F and 59.0°F.

Sea water temperature in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 61.9°F. The highest and lowest sea temperatures during the month were 67.1°F and 59.4°F.

Best time for vacation in Mackinac Island

Sunniest months:
July 14 days
August 14 days
September 12 days
Warmest months:
August 69.4 °F
July 69.3 °F
September 62.9 °F
Warmest sea temp:
August 67.3 °F
July 65.1 °F
September 62.7 °F
Coldest months:
February 23.1 °F
January 23.4 °F
December 30.7 °F
Rainiest months:
August 3 days
May 2 days
July 2 days
Windiest months:
November 13.5 mph
December 13.2 mph
April 11.7 mph

Mackinac Island on a weather map

Mackinac Island
+28°F
NE 10 mph
Feels like: +18°F
Precip.: 100%
Places in USA:
Name
°F
+36°F
+75°F
+75°F
+91°F
+84°F
+66°F
+72°F
+72°F
+32°F
+66°F
+63°F
+61°F
+59°F
+75°F
+39°F
24 Hours Forecast
Mackinac Island
Local time: 20:23
March 18, wednesday
2100
28°F
NE
10 mph
March 19, thursday
0000
30°F
NE
9 mph
0300
30°F
NE
9 mph
0600
28°F
E
7 mph
0900
28°F
E
6 mph
1200
28°F
SE
8 mph
1500
30°F
SE
5 mph
1800
30°F
E
3 mph
Units of measurement: °C / °F