Measurements:
°C
°F
Grand Isle
52°F
NW 9 mph
Feels like: 50°F
Precip: 0%
World Resorts USA Grand Isle Weather

Grand Isle Sea Water Temperature

Current Sea Water Temperature:
+61.0°F
Maximum Sea Water Temperature in January: 75.8°F
Minimum Sea Water Temperature in January: 55.2°F
Average water temperature in January: 63.7°F

Sea Water Temperature for the Last 10 Days:

January 29 61.0°F January 24 64.8°F
January 28 61.0°F January 23 64.8°F
January 27 65.0°F January 22 63.2°F
January 26 66.4°F January 21 64.0°F
January 25 66.2°F January 20 61.8°F

When is the Warmest Sea for Grand Isle?

According to our data for the last three years for Grand Isle the highest average sea water temperature was in August, July and June.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Grand Isle was 92.2°F. The maximum and minimum values were 90.0°F and 94.6°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Grand Isle was 92.5°F. The maximum and minimum values were 90.2°F and 95.0°F respectively.

Sea Water Temperature in June

Select Year: 2025 2024 2023

The average sea surface temperature in June 2025 for Grand Isle was 90.3°F. The maximum and minimum values were 87.2°F and 93.4°F respectively.

Best Time to Visit Grand Isle
The most sunny months:
October 18 days
September 15 days
November 14 days
The most warm months:
August 89.8 °F
July 89.3 °F
June 87.5 °F
Warmest sea temperature:
August 92.2 °F
July 91.3 °F
June 88.9 °F
The most cold months:
January 59.4 °F
February 62.4 °F
December 63.8 °F
The most rainy months:
July 5 days
June 4 days
August 4 days
The most windy months:
January 13 mph
March 12 mph
April 12 mph

Grand Isle on the Weather Map

USA Resorts:
NAME
Chicago 0
Hawaii +74
Honolulu +74
Houston +38
Las Vegas +48
Los Angeles +56
Maui +68
Miami +64
Miami Beach +70
New York +12
San Diego +60
San Francisco +50
Sarasota +58
Tampa +58
Washington +12
24 Hours Weather Forecast
Grand Isle
Local time: 09:54
29 jan, thursday
1200 54°F
NW
12 mph
1500 56°F
N
12 mph
1800 58°F
NE
8 mph
2100 58°F
N
4 mph
30 jan, friday
0000 58°F
N
10 mph
0300 58°F
NE
7 mph
0600 58°F
SW
2 mph
0900 56°F
SE
12 mph