Measurements:
°C
°F
Cayo Guillermo
78°F
W 24 mph
Feels like: 82°F
Precip: 0%
World Resorts Cuba Cayo Guillermo Weather

Cayo Guillermo Sea Water Temperature

Current Sea Water Temperature:
+82.0°F
Maximum Sea Water Temperature in March: 85.4°F
Minimum Sea Water Temperature in March: 77.2°F
Average water temperature in March: 81.5°F

Sea Water Temperature for the Last 10 Days:

March 31 82.0°F March 26 80.6°F
March 30 81.6°F March 25 79.8°F
March 29 81.6°F March 24 78.6°F
March 28 81.6°F March 23 77.2°F
March 27 81.0°F March 22 79.0°F

When is the Warmest Sea for Cayo Guillermo?

According to our data for the last three years for Cayo Guillermo the highest average sea water temperature was in September, August and July.

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 Cayo Guillermo was 91.4°F. The maximum and minimum values were 90.6°F and 92.6°F respectively.

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Cayo Guillermo was 91.0°F. The maximum and minimum values were 89.8°F and 92.8°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Cayo Guillermo was 89.2°F. The maximum and minimum values were 87.6°F and 90.2°F respectively.

Best Time to Visit Cayo Guillermo
The most sunny months:
March 13 days
April 13 days
May 11 days
The most warm months:
August 91.0 °F
July 90.5 °F
September 90.0 °F
Warmest sea temperature:
September 90.0 °F
August 89.9 °F
July 89.2 °F
The most cold months:
January 79.5 °F
February 80.4 °F
March 81.4 °F
The most rainy months:
May 7 days
October 7 days
August 6 days
The most windy months:
March 14 mph
November 14 mph
December 14 mph

Cayo Guillermo on the Weather Map

24 Hours Weather Forecast
Cayo Guillermo
Local time: 15:27
31 mar, tuesday
1800 78°F
W
25 mph
2100 78°F
W
28 mph
01 apr, wednesday
0000 78°F
W
26 mph
0300 78°F
W
24 mph
0600 78°F
W
22 mph
0900 80°F
W
22 mph
1200 78°F
W
21 mph
1500 80°F
W
21 mph