Climateby Month

Key West, FL climate by month

NOAA 1991-2020 normals · 2 ft elevation

Key West has hot and oppressively humid summers and mild winters. Highs peak at 91°F in August and fall to 76°F in January. The wettest month is September (about 16 wet days) and the driest is April (about 5). By our comfort score the best months are January, February and March.

Warmest month
91°F
August normal high
Coldest month
66°F
January normal low
Wet days a year
107
40.4 in of precipitation
Muggy days a year
284
dew point 65°F or higher

How warm is Key West?

Normal highs range from 76°F in January to 91°F in August.

60°70°80°90°100° January: normal high 76°F (24°C), low 66°F (19°C) 76° 66° February: normal high 77°F (25°C), low 67°F (19°C) March: normal high 80°F (27°C), low 69°F (21°C) April: normal high 83°F (28°C), low 73°F (23°C) May: normal high 86°F (30°C), low 76°F (24°C) June: normal high 89°F (32°C), low 79°F (26°C) July: normal high 90°F (32°C), low 81°F (27°C) August: normal high 91°F (33°C), low 81°F (27°C) 91° 81° September: normal high 89°F (32°C), low 79°F (26°C) October: normal high 86°F (30°C), low 77°F (25°C) November: normal high 81°F (27°C), low 72°F (22°C) December: normal high 78°F (26°C), low 68°F (20°C) JFMAMJJASOND

Bars run from the normal low to the normal high for each month.

How rainy is Key West?

September has the most wet days (about 16); the year brings about 40 in of precipitation.

January: 7 wet days February: 5 wet days March: 5 wet days April: 5 wet days 5 May: 8 wet days June: 11 wet days July: 12 wet days August: 15 wet days September: 16 wet days 16 October: 12 wet days November: 6 wet days December: 6 wet days JFMAMJJASOND

Wet day: at least 0.01 in of rain or melted snow, counted from daily records 1991-2020.

How humid is Key West?

Muggy days peak in July, at about 31 days.

January: 14 muggy days 14 February: 15 muggy days March: 16 muggy days April: 21 muggy days May: 28 muggy days June: 30 muggy days July: 31 muggy days 31 August: 31 muggy days September: 30 muggy days October: 29 muggy days November: 21 muggy days December: 18 muggy days JFMAMJJASOND

Muggy day: daily mean dew point of 65°F or higher, from hourly observations 1991-2020 at Key West International Airport, 1.7 mi E of the city center.

How much daylight?

Daylight ranges from about 10.6 hours in December to 13.6 hours in June.

January: 10.8 hours of daylight February: 11.3 hours of daylight March: 12.0 hours of daylight April: 12.7 hours of daylight May: 13.3 hours of daylight June: 13.6 hours of daylight 13.6 July: 13.5 hours of daylight August: 13.0 hours of daylight September: 12.3 hours of daylight October: 11.6 hours of daylight November: 11.0 hours of daylight December: 10.6 hours of daylight 10.6 JFMAMJJASOND
See all numbers
Monthly climate normals and day counts for Key West, 1991-2020
MonthHighLowPrecip.Wet daysMuggy daysDaylight
January 76°F66°F 1.8 in7 14 10.8 h
February 77°F67°F 1.5 in5 15 11.3 h
March 80°F69°F 1.5 in5 16 12.0 h
April 83°F73°F 2.1 in5 21 12.7 h
May 86°F76°F 3.1 in8 28 13.3 h
June 89°F79°F 4.2 in11 30 13.6 h
July 90°F81°F 3.6 in12 31 13.5 h
August 91°F81°F 5.4 in15 31 13.0 h
September 89°F79°F 7.2 in16 30 12.3 h
October 86°F77°F 5.7 in12 29 11.6 h
November 81°F72°F 2.0 in6 21 11.0 h
December 78°F68°F 2.2 in6 18 10.6 h

High and low: NOAA 1991-2020 normal daily high and low. Wet days: at least 0.01 in of rain or melted snow. Muggy days: daily mean dew point 65°F or higher.

Best months to visit Key West

By our comfort score, the best months are January, February and March.

Comfort score by month (0-100) and its parts, in days per month
MonthScoreComfortableNotable rainHot or cold
Jan 58930
Feb 59720
Mar 59730
Apr 56330
May 52041
Jun 47067
Jul 390718
Aug 350920
Sep 3801010
Oct 45181
Nov 52330
Dec 55730

Score = 40 × share of comfortable days + 25 × share of days without notable rain + 20 × share of days neither hot (90°F+) nor cold (high 40°F or below) + 15 × daylight. How the score works.

Frost dates in Key West

Key West is frost-free: NOAA's 1991-2020 normals record no nights at 32°F or below at Key West Intl Airport.

Station: Key West Intl Airport (USW00012836), NOAA 1991-2020 freeze probabilities. Frost dates for every city in Florida.

Hottest and coldest readings, 1991-2020

The highest reading was 95°F (September 20, 2018, and 1 other day); the lowest was 42°F (January 11, 2010).

From the temperature station's daily records with NOAA quality flags removed. Not an all-time record.

Near Key West

Similar climates elsewhere

Where the numbers come from

  • Temperature, rain, frost dates, humidity and wind by hour and cloud cover: Key West Intl Airport (USW00012836), 1.9 mi E of the city center, 4 ft . NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: Key West International Airport (722010-12836), 1.7 mi E of the city center, 1 ft . Hourly observations, 1991-2020.
  • Not available for this location: snowfall and snow depth (no station close enough or similar enough in elevation).

Distances from the city center (USGS). Methodology · Report an error