Current sea water temperature:
+37.6°F
| Minimum sea water temperature in December: | 43.9°F |
| Maximum sea water temperature in December: | 36.9°F |
| Average sea water temperature in December: | 39.5°F |
| more information | |
14 days
forecast
forecast
| Grand Marais |
monthly
weather
weather
| Grand Marais |
Sea water temperature for the last 10 days:
| December 30 | 37.6°F | December 25 | 38.1°F |
| December 29 | 37.0°F | December 24 | 38.3°F |
| December 28 | 36.9°F | December 23 | 37.0°F |
| December 27 | 37.2°F | December 22 | 37.9°F |
| December 26 | 37.4°F | December 21 | 39.2°F |
Monthly sea water temperature, °F
When is the warmest sea in Grand Marais?
Based on the data about daily sea water temperature for the last three years the warmest sea in Grand Marais was noticed in August, September and October.
Monthly Sea Temperatures in Grand Marais, °F
Sea water temperature in August, °F
Show year:
2025
2024
2023
The average sea water temperature in August of 2025 was 61.3°F. The highest and lowest sea temperatures during the month were 65.7°F and 55.9°F.
Sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 58.5°F. The highest and lowest sea temperatures during the month were 62.8°F and 55.0°F.
Sea water temperature in October, °F
Show year:
2025
2024
2023
The average sea water temperature in October of 2025 was 53.8°F. The highest and lowest sea temperatures during the month were 60.3°F and 49.6°F.
current
weather
weather
| Grand Marais |
weather in
January
January
| Grand Marais |
Best time for vacation in Grand Marais
Grand Marais on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Grand Marais
Local time: 17:24
December 30, tuesday
1800
16°F
S
8 mph
8 mph
2100
14°F
S
9 mph
9 mph
December 31, wednesday
0000
10°F
SE
11 mph
11 mph
0300
7°F
SE
11 mph
11 mph
0600
3°F
SE
13 mph
13 mph
0900
1°F
SE
16 mph
16 mph
1200
5°F
SE
16 mph
16 mph
1500
7°F
SE
15 mph
15 mph
