World Resorts USA Key West Weather

Key West weather in May

Weather in Key West: May

Average day temperature: 81.8°F
Average night temperature: 78.8°F
Sea water temperature: 82.2°F
Number of sunny days: 17 days
Day length: 13.1 - 13.6 hours
Number of rainy days: 5 days
Precipitation totals: 3.4 in.

Air temperature in May, °F

Show year:
2026
2025
2024

The highest day temperature during May of 2026 was 86°F. At the same time the lowest night temperature was 77°F. Daily and nightly averages during May were 83.8°F and 80.9°F.

Sea water temperature in Key West in May, °F

Show year:
2026
2025
2024

The average sea water temperature in May of 2026 was 84.3°F. The highest and lowest sea temperatures during the month were 86.9°F and 81.5°F.

Sunny, partly cloudy and cloudy days

Mostly all days in May are sunny but cloudy days are also possible.

Precipitation total in May, in.

Precipitation total value in Key West in May is 3.9 in. Other months of the year show relatively similar values.

Wind speed in May, mph

The average wind speed value in May is 11.6 mph

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in May is: 9.2.

Best time for vacation in Key West

Sunniest months:
May 17 days
March 16 days
April 16 days
Warmest months:
August 87.4 °F
July 86.9 °F
September 85.8 °F
Warmest sea temp:
August 87.2 °F
July 86.6 °F
September 86.1 °F
Coldest months:
January 72.0 °F
February 73.7 °F
December 75.4 °F
Rainiest months:
June 7 days
August 7 days
September 6 days
Windiest months:
November 14.7 mph
December 13.9 mph
January 13.8 mph

Key West on a weather map

Key West
+86°F
W 4 mph
Feels like: +95°F
Precip.: 3%
Places in USA:
Name
°F
+77°F
+77°F
+100°F
+79°F
+88°F
+86°F
+72°F
+79°F
+70°F
+68°F
+68°F
+95°F
+102°F
+88°F
+77°F
24 Hours Forecast
Key West
Local time: 15:21
June 08, monday
1800
84°F
W
6 mph
2100
82°F
NW
11 mph
June 09, tuesday
0000
82°F
W
15 mph
0300
82°F
NW
13 mph
0600
82°F
NW
9 mph
0900
82°F
NW
9 mph
1200
82°F
W
9 mph
1500
82°F
W
7 mph
Units of measurement: °C / °F