Measurements:
°C
°F
Cayo Guillermo
90°F
W 16 mph
Feels like: 104°F
Precip: 8%
World Resorts Cuba Cayo Guillermo Weather

Cayo Guillermo Sea Water Temperature

Current Sea Water Temperature:
+91.8°F
Maximum Sea Water Temperature in August: 93.8°F
Minimum Sea Water Temperature in August: 86.8°F
Average water temperature in August: 89.9°F

Sea Water Temperature for the Last 10 Days:

August 02 91.8°F July 28 90.8°F
August 01 91.6°F July 27 90.4°F
July 31 91.8°F July 26 91.0°F
July 30 91.6°F July 25 90.0°F
July 29 90.4°F July 24 89.8°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: 2026 2025 2024

The average sea surface temperature in July 2026 for Cayo Guillermo was 90.5°F. The maximum and minimum values were 89.6°F and 91.8°F respectively.

Best Time to Visit Cayo Guillermo
The most sunny months:
April 14 days
March 13 days
May 12 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:
October 7 days
May 6 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: 16:13
02 aug, sunday
1800 90°F
W
16 mph
2100 88°F
NW
13 mph
03 aug, monday
0000 86°F
N
6 mph
0300 84°F
N
7 mph
0600 84°F
N
7 mph
0900 86°F
NW
6 mph
1200 88°F
W
6 mph
1500 90°F
W
9 mph