Current sea water temperature:
+70.5°F
| Minimum sea water temperature in December: | 72.7°F |
| Maximum sea water temperature in December: | 56.8°F |
| Average sea water temperature in December: | 65.9°F |
| more information | |
14 days
forecast
forecast
| Grand Isle |
monthly
weather
weather
| Grand Isle |
Sea water temperature for the last 10 days:
| December 28 | 70.5°F | December 23 | 66.0°F |
| December 27 | 69.1°F | December 22 | 65.5°F |
| December 26 | 68.4°F | December 21 | 64.0°F |
| December 25 | 67.8°F | December 20 | 64.2°F |
| December 24 | 67.6°F | December 19 | 62.8°F |
Monthly sea water temperature, °F
When is the warmest sea in Grand Isle?
Based on the data about daily sea water temperature for the last three years the warmest sea in Grand Isle was noticed in August, July and June.
Monthly Sea Temperatures in Grand Isle, °F
Sea water temperature in August, °F
Show year:
2025
2024
2023
The average sea water temperature in August of 2025 was 87.9°F. The highest and lowest sea temperatures during the month were 90.1°F and 86.0°F.
Sea water temperature in July, °F
Show year:
2025
2024
2023
The average sea water temperature in July of 2025 was 88.3°F. The highest and lowest sea temperatures during the month were 90.5°F and 86.2°F.
Sea water temperature in June, °F
Show year:
2025
2024
2023
The average sea water temperature in June of 2025 was 86.2°F. The highest and lowest sea temperatures during the month were 89.1°F and 83.5°F.
current
weather
weather
| Grand Isle |
weather in
January
January
| Grand Isle |
Best time for vacation in Grand Isle
Grand Isle on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Grand Isle
Local time: 15:16
December 28, sunday
1800
68°F
N
12 mph
12 mph
2100
68°F
NE
11 mph
11 mph
December 29, monday
0000
68°F
NE
9 mph
9 mph
0300
66°F
NE
8 mph
8 mph
0600
66°F
E
8 mph
8 mph
0900
59°F
S
30 mph
30 mph
1200
55°F
S
26 mph
26 mph
1500
54°F
S
24 mph
24 mph
