May weather forecastCayo Guillermo, Cuba
May
Weather in May
Mingling the last fragments of spring with the onset of summer, May sets a differing tone weather-wise in Cayo Guillermo. Now reaching its peak, rainfall hits 168mm (6.61"), the highest level of precipitation thus far in the year. Prolonged daylight hours and a high UV index continue to define the daytime climate. Despite the substantial rainfall, temperatures remain warm, catalyzing the island's lush flora. As May rolls into June, the residents and visitors brace themselves for the peak summer weather.Temperature
May's advent notes a subtle adjustment in average high-temperature to a still tropical 31°C (87.8°F) from April. The nighttime temperature, during May, averages of 21°C (69.8°F).Rainfall
In Cayo Guillermo, in May, it is raining for 12 days, with typically 168mm (6.61") of accumulated precipitation. Throughout the year, there are 125 rainfall days, and 1200mm (47.24") of precipitation is accumulated.Sea temperature
In Cayo Guillermo, in May, the average water temperature is 27°C (80.6°F).Note: Swimming, diving, and other water endeavors at temperatures between 25°C (77°F) and 29°C (84.2°F) are considered enjoyable and satisfying for extended periods without discomfort.
Daylight
The average length of the day in May is 13h and 14min.On the first day of May in Cayo Guillermo, sunrise is at 06:41 and sunset at 19:41. On the last day of the month, sunrise is at 06:29 and sunset at 19:55 CDT.
Sunshine
In Cayo Guillermo, the average sunshine in May is 8h.UV index
The months with the highest UV index are April through August, with an average maximum UV index of 12. A UV Index value of 11, and more, symbolizes an excessive health risk from unprotected exposure to Sun's UV rays for average individuals.Note: In May, a daily UV index of 12 turns into the following recommendations:
Ensure all key precautions. Defense against sun exposure is critical. Limit your direct sun exposure, especially between 10 a.m. and 4 p.m., when UV radiation is strongest. Shade structures might not provide complete sun protection. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Sunscreen of at least SPF 30 should be applied generously and reapplied often on overcast days, especially post swim or outdoor exercise. Take caution! The UV rays from the Sun gain strength from sand and water reflections.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Cayo Guillermo, Cuba
- Average high temperature in May: 31°C
The warmest months (with the highest average high temperature) are July and August (33°C).
The month with the lowest average high temperature is January (27°C).
- Average low temperature in May: 21°C
The months with the highest average low temperature are June, July and August (23°C).
The coldest months (with the lowest average low temperature) are January and February (17°C).
Average rainfall in May
Cayo Guillermo, Cuba
- Average rainfall in May: 168mm
The wettest month (with the highest rainfall) is October (182mm).
The driest month (with the least rainfall) is December (39mm).
Average rainfall days in May
Cayo Guillermo, Cuba
- Average rainfall days in May: 12 days
The month with the highest number of rainy days is October (16 days).
The months with the least rainy days are February and April (5 days).
Average sea temperature in May
Cayo Guillermo, Cuba
- Average sea temperature in May: 27°C
The best months for swimming (with the highest average sea temperature) are June, July, August, September and October (29°C).
The coldest months (with the lowest average sea temperature) are January, February and March (25°C).
Average daylight in May /
Average sunshine in May
Cayo Guillermo, Cuba
- Average daylight in May: 13h and 12min
The month with the longest days is June (Average daylight: 13h and 30min).
The month with the shortest days is December (Average daylight: 10h and 48min).
- Average sunshine in May: 8h
The month with the most sunshine is April (Average sunshine: 9h).
The months with the least sunshine are January, February, June, September, October, November and December (Average sunshine: 7h).
Average UV index in May
Cayo Guillermo, Cuba
- Average UV index in May: 12
The months with the highest UV index are April, May, June, July and August (UV index 12).
The month with the lowest UV index is December (UV index 6).





