Key West Temperatures: Averages by Month
The numbers here tell you how hot and cold the weather usually is in Key West, Florida during each month of the year.
The average high and low temperatures are listed below by month and annually for Key West, in both degrees Fahrenheit and Celsius.
Maximums and minimums are only part of the temperature picture. To fill in the rest, there's information on how many days a month get above or below a given temperature.
To find out how often it rises over 70, 80 or 90 °F each month in Key West, scroll down farther. There are also monthly and yearly counts of nights with warm temperatures.
The first set of high and low temperatures are averages for 2010 to 2019. Everything else here is based on 1991 to 2020 weather.
| High °F | Low °F | High °C | Low °C | |
|---|---|---|---|---|
| 75 | 65 | January | 24 | 18 |
| 77 | 68 | February | 25 | 20 |
| 78 | 69 | March | 26 | 20 |
| 83 | 74 | April | 28 | 23 |
| 85 | 77 | May | 30 | 25 |
| 88 | 80 | June | 31 | 26 |
| 89 | 81 | July | 32 | 27 |
| 90 | 81 | August | 32 | 27 |
| 88 | 80 | September | 31 | 27 |
| 85 | 77 | October | 30 | 25 |
| 81 | 72 | November | 27 | 22 |
| 78 | 69 | December | 26 | 21 |
| 83 | 74 | Year | 28 | 24 |
| High °F | Low °F | High °C | Low °C | |
|---|---|---|---|---|
| 76 | 66 | January | 24 | 19 |
| 77 | 67 | February | 25 | 20 |
| 80 | 69 | March | 26 | 21 |
| 83 | 73 | April | 28 | 23 |
| 86 | 76 | May | 30 | 25 |
| 89 | 79 | June | 32 | 26 |
| 90 | 81 | July | 32 | 27 |
| 91 | 81 | August | 33 | 27 |
| 89 | 79 | September | 32 | 26 |
| 86 | 77 | October | 30 | 25 |
| 81 | 72 | November | 27 | 22 |
| 78 | 68 | December | 25 | 20 |
| 84 | 74 | Year | 29 | 23 |
Days of Hot Weather in Key West
It's not normal for the temperature to rise above 100 °F (38 °C) in Key West. But it does climb into the 90s for much of July and August. Even during winter months, Key West usually has many days of 80-degree weather.
| 70 °F 21 °C |
80 °F 27 °C |
90 °F 32 °C | |
|---|---|---|---|
| January | 26 | 8 | 0 |
| February | 25 | 11 | 0 |
| March | 29 | 17 | 0 |
| April | 30 | 25 | 0 |
| May | 31 | 30 | 1 |
| June | 30 | 30 | 7 |
| July | 31 | 31 | 18 |
| August | 31 | 31 | 20 |
| September | 30 | 30 | 10 |
| October | 31 | 30 | 1 |
| November | 30 | 20 | 0 |
| December | 28 | 13 | 0 |
| Year | 352 | 274 | 57 |
Number of Warm Nights a Month
Nights at Key West are consistently warm, staying above 50 °F nearly throughout the year. From June to September, the temperature normally never gets any colder than 70 degrees.
| 50 °F 10 °C |
60 °F 16 °C |
70 °F 21 °C | |
|---|---|---|---|
| January | 30 | 24 | 7 |
| February | 28 | 24 | 9 |
| March | 31 | 28 | 14 |
| April | 30 | 30 | 22 |
| May | 31 | 31 | 29 |
| June | 30 | 30 | 30 |
| July | 31 | 31 | 31 |
| August | 31 | 31 | 31 |
| September | 30 | 30 | 30 |
| October | 31 | 31 | 30 |
| November | 30 | 29 | 20 |
| December | 31 | 27 | 12 |
| Year | 363 | 346 | 265 |
References
Jay Lawrimore, Ron Ray, Scott Applequist, Bryant Korzeniewski, Matthew Menne. 2016. Global Summary of the Month and Year, Version 1.0. NOAA National Centers for Environmental Information.
NOAA National Centers for Environmental Information (NCEI). Climate Normals.