Key West, FL Climate & Monthly Averages

Florida, United States 🇺🇸 · tropical wet-and-dry climate
Annual avg
78°
Hottest month
August
Coldest month
January
Rainy days / yr
136
Sunshine
10.8 h/day
Right now: 87° and partly cloudy - see live conditions

The climate of Key West

Weather in Key West is shaped by its tropical wet-and-dry climate - expect year-round warmth split between a rainy season and a pronounced dry season. August afternoons typically reach 86°F (30°C), while January highs hover near 73°F (23°C). Annual precipitation averages 41.4 inches (1052 mm) over about 136 rainy days.

Climate quick facts

  • Hottest month: August - highs near 86°F (30°C)
  • Coldest month: January - highs near 73°F (23°C)
  • Record high: 89°F (32°C) · Record low: 54°F (12°C) (2015–2024)
  • Wettest month: September (19 rainy days) · Sunniest: July (12.2 h sun/day)
  • Climate type: tropical wet-and-dry - year-round warmth split between a rainy season and a pronounced dry season

Temperatures through the year

The warmest stretch of the year centers on August. Highs average 86°F (30°C) and overnight lows stay near 82°F (28°C). The coolest month is January, with typical highs of 73°F (23°C) and lows around 69°F (20°C). Based on 2015–2024 weather data, temperatures have reached as high as 89°F (32°C) and dropped as low as 54°F (12°C).

Rain, sun and snow

September is usually the wettest month. It brings about 6.6 inches (168 mm) of rain over 19 days, while February is the driest. July brings the most sunshine, averaging 12.2 hours of sun a day.

Monthly climate table

Monthly averages for Key West based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 73° 69° 8 1.9 in 9.4 h/day 78%
February 74° 70° 6 1.4 in 10.3 h/day 79%
March 76° 73° 4 1.5 in 11.0 h/day 76%
April 78° 75° 6 1.6 in 12.1 h/day 76%
May 81° 78° 11 3.6 in 12.1 h/day 76%
June 83° 80° 16 5.5 in 11.3 h/day 79%
July 85° 82° 15 3.6 in 12.2 h/day 77%
August 86° 82° 18 5.1 in 11.5 h/day 77%
September 85° 81° 19 6.6 in 10.5 h/day 78%
October 82° 79° 16 5.0 in 10.0 h/day 77%
November 79° 76° 8 3.0 in 9.7 h/day 77%
December 75° 72° 7 2.6 in 9.3 h/day 80%

Key West month by month

Key West weather in January

January brings highs around 73°F (23°C), lows near 69°F (20°C), about 8 wet days - typically the coldest month of the year in Key West.

Key West weather in February

February brings highs around 74°F (23°C), lows near 70°F (21°C), about 6 wet days - typically the driest month of the year in Key West.

Key West weather in March

March brings highs around 76°F (24°C), lows near 73°F (23°C), about 4 wet days.

Key West weather in April

April brings highs around 78°F (26°C), lows near 75°F (24°C), about 6 wet days.

Key West weather in May

May brings highs around 81°F (27°C), lows near 78°F (25°C), about 11 wet days.

Key West weather in June

June brings highs around 83°F (29°C), lows near 80°F (27°C), about 16 wet days.

Key West weather in July

July brings highs around 85°F (30°C), lows near 82°F (28°C), about 15 wet days - typically the sunniest month of the year in Key West.

Key West weather in August

August brings highs around 86°F (30°C), lows near 82°F (28°C), about 18 wet days - typically the hottest month of the year in Key West.

Key West weather in September

September brings highs around 85°F (29°C), lows near 81°F (27°C), about 19 wet days - typically the wettest month of the year in Key West.

Key West weather in October

October brings highs around 82°F (28°C), lows near 79°F (26°C), about 16 wet days.

Key West weather in November

November brings highs around 79°F (26°C), lows near 76°F (24°C), about 8 wet days.

Key West weather in December

December brings highs around 75°F (24°C), lows near 72°F (22°C), about 7 wet days.

Seasons in Key West

March through May

March through May in Key West is mild and warm, with daytime highs averaging 78°F (26°C) and nights around 75°F (24°C); expect showers on roughly 22 days across the season.

June through August

June through August in Key West brings hot afternoons, with daytime highs averaging 85°F (29°C) and nights around 81°F (27°C); expect showers on roughly 49 days across the season. With the humidity factored in, afternoons often feel hotter than the thermometer reads - run the numbers through the humidity and dew point converter to see why.

September through November

September through November in Key West is hot, with daytime highs averaging 82°F (28°C) and nights around 78°F (26°C); expect showers on roughly 44 days across the season.

December through February

December through February in Key West brings comfortable warmth, with daytime highs averaging 74°F (23°C) and nights around 70°F (21°C); expect showers on roughly 21 days across the season.

Climate questions, answered

What is the average temperature in Key West?
Key West averages 78°F (26°C) across the year, with typical daytime highs of 80°F (26°C) and nighttime lows around 76°F (25°C).
Is Key West hot in summer?
Warm to hot: August, the warmest month, averages highs of 86°F (30°C) - hot afternoons happen, but extremes are not the norm.
Is Key West cold in winter?
No - winters are mild. Even January nights only average 69°F (20°C).
How many rainy days does Key West get in a year?
Roughly 136 wet days a year. September carries the most rain; February the least.

Best time to visit Key West

The best time to visit Key West is generally December to April, when these months combine the driest skies with the most comfortable heat. Daytime temperatures in that window typically sit near 75°F (24°C).

Pack for Key West with a compact umbrella or rain shell - showers are a regular feature; moisture-wicking fabrics to cope with the humidity. Evenings can feel noticeably cooler than afternoons - August nights average 82°F (28°C).

Key West temperature records (2015-2024)

Highest recorded
89°
in August
Lowest recorded
54°
in January
Annual precipitation
41.4"
Snowy days / yr
0

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.