Measurements:
°C
°F
Grand Cayman
86°F
NW 16 mph
Feels like: 94°F
Precip: 0%
World Resorts Cayman Islands Grand Cayman Weather

Grand Cayman Sea Water Temperature

Current Sea Water Temperature:
+88.0°F
Maximum Sea Water Temperature in May: 90.4°F
Minimum Sea Water Temperature in May: 84.2°F
Average water temperature in May: 86.9°F

Sea Water Temperature for the Last 10 Days:

May 29 88.0°F May 24 88.6°F
May 28 88.2°F May 23 88.6°F
May 27 88.6°F May 22 88.4°F
May 26 88.8°F May 21 88.2°F
May 25 88.6°F May 20 88.4°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: 2025 2024 2023

The average sea surface temperature in August 2025 for Grand Cayman was 91.0°F. The maximum and minimum values were 89.8°F and 91.6°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 11 days
March 10 days
September 10 days
The most warm months:
August 91.3 °F
July 91.1 °F
September 91.0 °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 +86
George Town +86
Grand Cayman +86
Little Cayman +86
24 Hours Weather Forecast
Grand Cayman
Local time: 00:49
30 may, saturday
0300 86°F
NW
15 mph
0600 86°F
NW
11 mph
0900 86°F
NW
12 mph
1200 86°F
NW
13 mph
1500 86°F
NW
16 mph
1800 86°F
NW
16 mph
2100 86°F
NW
17 mph
31 may, sunday
0000 86°F
NW
17 mph