Measurements:
°C
°F
Grand Cayman
90°F
W 14 mph
Feels like: 102°F
Precip: 7%
World Resorts Cayman Islands Grand Cayman Weather

Grand Cayman Sea Water Temperature

Current Sea Water Temperature:
+91.8°F
Maximum Sea Water Temperature in September: 92.0°F
Minimum Sea Water Temperature in September: 87.6°F
Average water temperature in September: 90.1°F

Sea Water Temperature for the Last 10 Days:

September 08 91.8°F September 03 91.6°F
September 07 92.0°F September 02 91.6°F
September 06 92.0°F September 01 91.6°F
September 05 91.4°F August 31 91.2°F
September 04 91.4°F August 30 91.2°F

When is the Warmest Sea for Grand Cayman?

According to our data for the last three years for Grand Cayman the highest average sea water temperature was in September, August and October.

Average Water Temperature by Month, °F

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Grand Cayman was 91.6°F. The maximum and minimum values were 91.0°F and 92.0°F respectively.

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for Grand Cayman was 90.8°F. The maximum and minimum values were 90.2°F and 91.4°F respectively.

Sea Water Temperature in October

Select Year: 2025 2024 2023

The average sea surface temperature in October 2025 for Grand Cayman was 90.7°F. The maximum and minimum values were 89.2°F and 92.6°F respectively.

Best Time to Visit Grand Cayman
The most sunny months:
July 10 days
March 10 days
September 10 days
The most warm months:
August 91.1 °F
September 91.0 °F
July 90.9 °F
Warmest sea temperature:
September 90.1 °F
August 89.9 °F
October 89.5 °F
The most cold months:
January 83.4 °F
February 83.6 °F
March 84.3 °F
The most rainy months:
October 8 days
May 5 days
November 5 days
The most windy months:
December 16 mph
November 16 mph
January 16 mph

Grand Cayman on the Weather Map

Cayman Islands Resorts:
NAME
Cayman Brac +90
George Town +90
Grand Cayman +90
Little Cayman +90
24 Hours Weather Forecast
Grand Cayman
Local time: 14:43
08 sep, tuesday
1500 90°F
W
14 mph
1800 90°F
W
14 mph
2100 90°F
W
11 mph
09 sep, wednesday
0000 90°F
W
13 mph
0300 90°F
W
16 mph
0600 90°F
W
12 mph
0900 90°F
W
12 mph
1200 90°F
W
13 mph