FL · climate averages
Key West Weather by Month
These are climate averages, not a forecast. Station Key West Intl AP (USW00012836), 1.1 miles from downtown, elevation 4 ft.
Key West's warmest month is August (avg high 90.6°F), coldest is January (avg low 65.5°F) and wettest is September (7.24 in), per NOAA 1991–2020 climate normals.
- Warmest high August 90.6°F
- Coldest low January 65.5°F
- Wettest month September 7.24 in
- Year of rain 12 months 40.44 in
Monthly Averages
Key West's 12 monthly precipitation normals add up to 40.44 inches a year.
March is the driest month, with a precipitation normal of 1.53 inches.
Key West averages 106.6 days a year with at least 0.01 inch of precipitation.
| Month | Avg high | Avg low | Precipitation | Days ≥ 0.01 in |
|---|---|---|---|---|
| January | 75.8°F | 65.5°F | 1.83 in | 6.9 |
| February | 77.4°F | 67.1°F | 1.54 in | 4.9 |
| March | 79.6°F | 69.3°F | 1.53 in | 4.8 |
| April | 82.6°F | 73.1°F | 2.07 in | 4.5 |
| May | 85.9°F | 76.4°F | 3.12 in | 7.5 |
| June | 88.7°F | 79.4°F | 4.23 in | 11.2 |
| July | 90.2°F | 80.6°F | 3.63 in | 11.6 |
| August | 90.6°F | 80.5°F | 5.37 in | 14.6 |
| September | 89.0°F | 79.2°F | 7.24 in | 15.8 |
| October | 85.8°F | 76.8°F | 5.67 in | 12.1 |
| November | 81.0°F | 72.2°F | 2.05 in | 6.3 |
| December | 77.7°F | 68.3°F | 2.16 in | 6.4 |
Warmest, Coldest and Wettest Months
The warmest month is August, with an average high of 90.6°F.
The coldest month is January, with an average low of 65.5°F.
The wettest month is September, at 7.24 inches of precipitation over about 15.8 days.
July and August are the only months in Key West with an average high of at least 90°F.
In Key West, the warmest average high is only 25.1°F above the coldest average low.
In August, the average high in Key West is 10.1°F above the average low.
Best Months to Visit Key West for Weather
January, February, March, April, November and December meet the weather rule on this page: an average high from 65 to 85°F and precipitation below 3.37 inches.
The rule keeps a month when the average high is from 65 to 85°F and precipitation is below 3.37 inches, the mean of the twelve monthly precipitation normals.
- January · 75.8°F
- February · 77.4°F
- March · 79.6°F
- April · 82.6°F
- November · 81.0°F
- December · 77.7°F
Nearby cities
Miami is the closest other city on this site, 127.5 miles away. Its July average high is 90.6°F, 0.4°F warmer than Key West.
About This Data
Source: NOAA National Centers for Environmental Information (NCEI), U.S. Climate Normals 1991–2020. Station: KEY WEST INTL AP (USW00012836), 1.1 mi from downtown, elevation 4 ft. Climate normals are 30-year averages, not forecasts. MonthSky is not affiliated with NOAA.
Palecki, Michael; Durre, Imke; Applequist, Scott; Arguez, Anthony; Lawrimore, Jay (2021). U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991-2020). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/wck8-er13. Accessed 2026-10-21.
U.S. Government work.
NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
These pages are built automatically from public NOAA data.
U.S. Monthly Climate Normals (1991-2020) dataset
NCEI dataset landing page for the monthly normals
FAQ
What is the hottest month in Key West?
August is the warmest, with an average high of 90.6°F.
What is the wettest month in Key West?
September is the wettest, at 7.24 inches over about 15.8 days.
How many rainy days does Key West get a year?
The monthly counts of days with at least 0.01 inch of precipitation add up to 106.6 days.
When is the best time to visit Key West for weather?
January, February, March, April, November and December meet the rule used on this page: average high from 65 to 85°F and precipitation below the monthly mean of 3.37 inches.