May weather in Marathon, FL
The average temperature in Marathon in May is 81.7°F (75.8°F–87.5°F). Average precipitation: 3.36 inches.
May is a spring month in Marathon, and is warmer than the annual average of 78.8°F. Daily temperatures swing about 11.7°F between overnight low and afternoon high. Expect about 8 days with precipitation. Daylight averages about 13h 12m. For travel, May is a comfortable month to visit.
Avg High
87.5°F
Avg Low
75.8°F
Precipitation
3.36 in
Daylight
13h 12m
May records in Marathon
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| May 1 | 89.1°F (2002) | 69.1°F (2006) | 1.58 in (2013) |
| May 2 | 93.0°F (2019) | 69.1°F (1999) | 2.23 in (2013) |
| May 3 | 91.9°F (2019) | 69.1°F (1999) | 1.59 in (2001) |
| May 4 | 91.9°F (2019) | 66.9°F (2006) | 0.21 in (2004) |
| May 5 | 95.0°F (2019) | 69.1°F (2006) | 0.49 in (2005) |
| May 6 | 95.0°F (2019) | 69.1°F (2016) | 0.13 in (2016) |
| May 7 | 91.9°F (2019) | 68.0°F (2016) | 0.10 in (2003) |
| May 8 | 93.0°F (2019) | 64.0°F (2016) | 0.43 in (2022) |
| May 9 | 91.9°F (2019) | 66.9°F (2001) | 0.15 in (2001) |
| May 10 | 91.9°F (2019) | 66.9°F (2020) | 2.81 in (2020) |
| May 11 | 91.9°F (2008) | 69.1°F (2005) | 0.76 in (2020) |
| May 12 | 95.0°F (2019) | 72.0°F (2022) | 1.45 in (2025) |
| May 13 | 95.0°F (2019) | 72.0°F (2001) | 0.59 in (2018) |
| May 14 | 96.1°F (2019) | 70.0°F (2001) | 5.76 in (2020) |
| May 15 | 91.9°F (1998) | 72.0°F (2007) | 1.45 in (2007) |
| May 16 | 91.0°F (2011) | 70.0°F (2001) | 1.34 in (2019) |
| May 17 | 93.9°F (2010) | 69.1°F (2001) | 1.49 in (2012) |
| May 18 | 93.0°F (2016) | 69.1°F (2001) | 1.24 in (2016) |
| May 19 | 93.0°F (2008) | 71.1°F (1998) | 1.12 in (2002) |
| May 20 | 91.9°F (2008) | 69.1°F (2006) | 7.08 in (2024) |
| May 21 | 91.9°F (2008) | 73.0°F (2005) | 2.47 in (2018) |
| May 22 | 93.0°F (2008) | 72.0°F (2021) | 0.40 in (2023) |
| May 23 | 91.9°F (2008) | 71.1°F (2014) | 1.00 in (2023) |
| May 24 | 91.9°F (2008) | 72.0°F (2014) | 3.45 in (2020) |
| May 25 | 91.9°F (2003) | 72.0°F (2001) | 2.40 in (2018) |
| May 26 | 93.0°F (2017) | 72.0°F (2004) | 0.27 in (2007) |
| May 27 | 93.0°F (2017) | 72.0°F (2004) | 2.70 in (2013) |
| May 28 | 93.0°F (2017) | 73.0°F (2008) | 0.82 in (2008) |
| May 29 | 91.9°F (2017) | 73.9°F (2013) | 2.40 in (2013) |
| May 30 | 91.9°F (2005) | 71.1°F (1999) | 1.59 in (2013) |
| May 31 | 93.0°F (2005) | 73.0°F (1999) | 1.33 in (2012) |