May weather in Costa Mesa, CA
The average temperature in Costa Mesa in May is 65.3°F (59.3°F–71.3°F). Average precipitation: 0.27 inches.
May is a spring month in Costa Mesa, and is warmer than the annual average of 64.9°F. Daily temperatures swing about 12°F between overnight low and afternoon high. Expect about 2 days with precipitation. Daylight averages about 13h 45m. For travel, May is one of the best months of the year to visit.
Avg High
71.3°F
Avg Low
59.3°F
Precipitation
0.27 in
Daylight
13h 45m
May records in Costa Mesa
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| May 1 | 99.0°F (2014) | 48.9°F (1999) | 0.03 in (2023) |
| May 2 | 98.1°F (2004) | 52.0°F (2002) | 0.25 in (2003) |
| May 3 | 96.1°F (2004) | 51.1°F (2018) | 0.38 in (2003) |
| May 4 | 84.9°F (2018) | 53.1°F (1999) | 0.32 in (2023) |
| May 5 | 86.0°F (2020) | 51.1°F (1999) | 0.11 in (2023) |
| May 6 | 91.9°F (2020) | 53.1°F (2023) | 0.21 in (2005) |
| May 7 | 93.0°F (2007) | 51.1°F (2017) | 0.39 in (2015) |
| May 8 | 91.9°F (2007) | 51.1°F (2017) | 0.11 in (2015) |
| May 9 | 84.0°F (2025) | 54.0°F (2003) | 0.05 in (2011) |
| May 10 | 91.0°F (2025) | 50.0°F (2003) | 0.00 in (1999) |
| May 11 | 82.0°F (2014) | 53.1°F (2003) | 0.01 in (2018) |
| May 12 | 93.0°F (2014) | 51.1°F (2010) | 0.02 in (2008) |
| May 13 | 99.0°F (2014) | 55.0°F (2000) | 0.00 in (1999) |
| May 14 | 106.0°F (2014) | 54.0°F (2000) | 0.37 in (2015) |
| May 15 | 102.0°F (2014) | 54.0°F (2003) | 0.19 in (2015) |
| May 16 | 93.0°F (2008) | 51.1°F (2011) | 0.21 in (2019) |
| May 17 | 90.0°F (2008) | 53.1°F (2011) | 0.10 in (2011) |
| May 18 | 87.1°F (2008) | 53.1°F (2011) | 0.26 in (2011) |
| May 19 | 82.9°F (2008) | 53.1°F (2019) | 0.11 in (2019) |
| May 20 | 88.0°F (2017) | 55.0°F (2003) | 0.04 in (2022) |
| May 21 | 81.0°F (2005) | 54.0°F (2002) | 0.01 in (2006) |
| May 22 | 79.0°F (2005) | 54.0°F (2002) | 0.57 in (2006) |
| May 23 | 79.0°F (2017) | 54.0°F (2008) | 0.03 in (2008) |
| May 24 | 84.0°F (2021) | 53.1°F (2008) | 0.02 in (2008) |
| May 25 | 81.0°F (2021) | 51.1°F (2008) | 0.01 in (2000) |
| May 26 | 79.0°F (2020) | 55.9°F (2008) | 0.01 in (2019) |
| May 27 | 84.9°F (2000) | 53.1°F (2019) | 0.00 in (1999) |
| May 28 | 82.9°F (2000) | 53.1°F (2019) | 0.00 in (1999) |
| May 29 | 84.0°F (2010) | 55.9°F (2008) | 0.00 in (1999) |
| May 30 | 90.0°F (2025) | 51.1°F (2011) | 0.02 in (2018) |
| May 31 | 82.0°F (2004) | 53.1°F (2011) | 0.00 in (1999) |