May weather in Union City, CA
The average temperature in Union City in May is 61.5°F (51.9°F–71.1°F). Average precipitation: 0.50 inches.
May is a spring month in Union City, and is warmer than the annual average of 59.5°F. Daily temperatures swing about 19.2°F between overnight low and afternoon high. Expect about 3 days with precipitation. Daylight averages about 14h 2m. For travel, May is one of the best months of the year to visit.
Avg High
71.1°F
Avg Low
51.9°F
Precipitation
0.50 in
Daylight
14h 2m
May records in Union City
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| May 1 | 90.0°F (2014) | 43.0°F (2008) | 0.13 in (2009) |
| May 2 | 90.0°F (2013) | 44.1°F (2023) | 0.19 in (2023) |
| May 3 | 89.1°F (2013) | 43.0°F (2022) | 0.21 in (2003) |
| May 4 | 89.1°F (2017) | 43.0°F (2025) | 0.83 in (2024) |
| May 5 | 87.1°F (2011) | 44.1°F (2024) | 0.56 in (2005) |
| May 6 | 84.9°F (2001) | 45.0°F (2024) | 0.18 in (2023) |
| May 7 | 93.0°F (2001) | 46.0°F (2010) | 0.17 in (2000) |
| May 8 | 96.1°F (2001) | 45.0°F (2021) | 0.27 in (2000) |
| May 9 | 84.0°F (2025) | 43.0°F (2003) | 0.25 in (2005) |
| May 10 | 87.1°F (2001) | 44.1°F (1999) | 0.00 in (1998) |
| May 11 | 84.0°F (2012) | 41.0°F (2022) | 0.08 in (1998) |
| May 12 | 84.9°F (2014) | 44.1°F (2000) | 0.29 in (1998) |
| May 13 | 91.9°F (2014) | 44.1°F (2000) | 0.06 in (1998) |
| May 14 | 91.9°F (2014) | 46.9°F (1999) | 0.08 in (2015) |
| May 15 | 97.0°F (2008) | 44.1°F (1999) | 0.29 in (2000) |
| May 16 | 96.1°F (2008) | 45.0°F (1999) | 0.54 in (2019) |
| May 17 | 93.9°F (2009) | 45.0°F (1998) | 0.15 in (2011) |
| May 18 | 91.0°F (2009) | 45.0°F (1998) | 0.16 in (2019) |
| May 19 | 86.0°F (2016) | 45.0°F (2011) | 0.81 in (2019) |
| May 20 | 90.0°F (2000) | 44.1°F (2021) | 0.27 in (2002) |
| May 21 | 97.0°F (2000) | 44.1°F (2021) | 0.10 in (2002) |
| May 22 | 91.9°F (2000) | 46.0°F (2010) | 0.14 in (2006) |
| May 23 | 90.0°F (2000) | 45.0°F (2010) | 0.00 in (1998) |
| May 24 | 87.1°F (2022) | 45.0°F (2013) | 0.00 in (1998) |
| May 25 | 91.0°F (2020) | 48.0°F (2011) | 0.20 in (2010) |
| May 26 | 91.0°F (2020) | 45.0°F (2024) | 0.15 in (2019) |
| May 27 | 89.1°F (2003) | 46.9°F (2021) | 0.12 in (1998) |
| May 28 | 91.0°F (2003) | 48.0°F (2008) | 0.51 in (1998) |
| May 29 | 82.9°F (2018) | 46.0°F (2011) | 0.05 in (1998) |
| May 30 | 98.1°F (2001) | 46.9°F (2022) | 0.00 in (1998) |
| May 31 | 98.1°F (2001) | 46.0°F (2022) | 0.09 in (2011) |