August weather in Key West, FL
The average temperature in Key West in August is 84.1°F (78.5°F–89.7°F). Average precipitation: 6.13 inches.
August is a summer month in Key West, and is warmer than the annual average of 77.4°F. Daily temperatures swing about 11.2°F between overnight low and afternoon high. Expect about 14 days with precipitation. Daylight averages about 12h 52m. For travel, August is a wet month.
Avg High
89.7°F
Avg Low
78.5°F
Precipitation
6.13 in
Daylight
12h 52m
August records in Key West
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 93.0°F (2024) | 75.9°F (2018) | 0.56 in (2018) |
| August 2 | 91.9°F (2016) | 73.0°F (2016) | 2.81 in (2016) |
| August 3 | 93.0°F (2017) | 73.9°F (2014) | 1.78 in (2024) |
| August 4 | 93.0°F (2025) | 73.9°F (2014) | 1.30 in (2024) |
| August 5 | 93.0°F (2017) | 75.9°F (2013) | 0.54 in (2018) |
| August 6 | 93.0°F (2023) | 75.0°F (2012) | 1.01 in (2012) |
| August 7 | 93.9°F (2023) | 75.0°F (2014) | 0.92 in (2017) |
| August 8 | 93.9°F (2023) | 75.0°F (2025) | 0.40 in (2025) |
| August 9 | 93.0°F (2021) | 73.0°F (2013) | 0.71 in (2015) |
| August 10 | 93.0°F (2020) | 75.9°F (2013) | 0.21 in (2013) |
| August 11 | 93.9°F (2023) | 75.0°F (2025) | 0.43 in (2023) |
| August 12 | 91.9°F (2020) | 75.0°F (2018) | 1.74 in (2023) |
| August 13 | 91.9°F (2020) | 75.9°F (2021) | 0.24 in (2021) |
| August 14 | 93.0°F (2023) | 75.9°F (2016) | 0.50 in (2021) |
| August 15 | 93.0°F (2017) | 75.0°F (2013) | 0.45 in (2019) |
| August 16 | 93.0°F (2017) | 77.0°F (2015) | 1.22 in (2024) |
| August 17 | 93.0°F (2014) | 77.0°F (2016) | 1.01 in (2025) |
| August 18 | 93.0°F (2014) | 77.0°F (2025) | 0.09 in (2017) |
| August 19 | 93.0°F (2022) | 75.0°F (2017) | 0.67 in (2023) |
| August 20 | 93.9°F (2022) | 73.0°F (2013) | 5.72 in (2019) |
| August 21 | 93.9°F (2022) | 71.1°F (2020) | 2.07 in (2020) |
| August 22 | 93.0°F (2022) | 75.9°F (2015) | 0.29 in (2015) |
| August 23 | 91.9°F (2014) | 75.0°F (2024) | 1.40 in (2016) |
| August 24 | 91.0°F (2014) | 75.0°F (2016) | 1.43 in (2016) |
| August 25 | 91.9°F (2025) | 73.0°F (2012) | 1.04 in (2015) |
| August 26 | 91.9°F (2022) | 73.0°F (2021) | 1.23 in (2012) |
| August 27 | 93.0°F (2022) | 73.9°F (2015) | 1.87 in (2025) |
| August 28 | 91.9°F (2022) | 75.0°F (2013) | 0.36 in (2015) |
| August 29 | 93.0°F (2014) | 73.0°F (2013) | 0.80 in (2023) |
| August 30 | 93.0°F (2014) | 73.0°F (2022) | 0.62 in (2015) |
| August 31 | 91.9°F (2017) | 73.9°F (2018) | 0.77 in (2014) |