Weather on May 21
San Mateo, CA
55 Years of Data
Avg High
68°F
Avg Low
51°F
Warmest
2000
75°F avg
Coldest
1982
55°F avg
About This Date
May 21st in San Mateo, CA typically brings mild spring weather, with average highs around 68°F and lows near 51°F. Over 55 years of records, the warmest May 21st was in 2000 (75°F average), while the coldest was 1982 (55°F) — a 20°F range across recorded history. Rain or other precipitation has occurred on about 9% of May 21st dates historically, with the wettest May 21st recording 0.61" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for May 21st in San Mateo, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 72° | 49° | 60° | — | — |
| 2024 | 77° | 52° | 64° | — | — |
| 2023 | 68° | 54° | 61° | — | — |
| 2022 | 72° | 50° | 61° | — | — |
| 2021 | 64° | 51° | 58° | — | — |
| 2020 | 70° | 52° | 61° | — | — |
| 2019 | 62° | 52° | 57° | 0.25" | — |
| 2018 | 67° | 52° | 59° | — | — |
| 2017 | 77° | 53° | 65° | — | — |
| 2016 | 64° | 54° | 59° | — | — |
| 2015 | 67° | 55° | 61° | 0.03" | — |
| 2014 | 71° | 56° | 63° | — | — |
| 2013 | 63° | 49° | 56° | — | — |
| 2012 | 65° | 52° | 58° | — | — |
| 2011 | 62° | 52° | 57° | — | — |
| 2010 | 61° | 50° | 55° | — | — |
| 2009 | 67° | 46° | 56° | — | — |
| 2008 | 63° | 50° | 56° | — | — |
| 2007 | 70° | 49° | 59° | — | — |
| 2006 | 68° | 52° | 60° | 0.61" | — |
| 2005 | 71° | 54° | 62° | — | — |
| 2004 | 62° | 56° | 59° | — | — |
| 2003 | 68° | 52° | 60° | — | — |
| 2002 | 62° | 51° | 57° | 0.1" | — |
| 2001 | 76° | 52° | 64° | — | — |
| 2000warmest | 92° | 59° | 75° | — | — |
| 1999 | 66° | 46° | 56° | — | — |
| 1998 | 62° | 52° | 57° | — | — |
| 1997 | 72° | 53° | 62° | — | — |
| 1996 | 66° | 53° | 60° | 0.08" | — |
| 1995 | 59° | 53° | 56° | — | — |
| 1994 | 63° | 52° | 57° | — | — |
| 1993 | 70° | 57° | 63° | — | — |
| 1992 | 76° | 53° | 64° | — | — |
| 1991 | 68° | 49° | 58° | — | — |
| 1990 | 71° | 53° | 62° | — | — |
| 1989 | 63° | 51° | 57° | — | — |
| 1988 | 89° | 53° | 71° | — | — |
| 1987 | 63° | 52° | 57° | — | — |
| 1986 | 63° | 49° | 56° | — | — |
| 1985 | 72° | 50° | 61° | — | — |
| 1984 | 66° | 49° | 57° | — | — |
| 1983 | 68° | 51° | 60° | — | — |
| 1982coldest | 62° | 49° | 55° | — | — |
| 1981 | 63° | 52° | 57° | — | — |
| 1980 | 64° | 51° | 58° | — | — |
| 1979 | 67° | 57° | 62° | — | — |
| 1978 | 65° | 55° | 60° | — | — |
| 1977 | 64° | 51° | 58° | — | — |
| 1976 | 77° | 49° | 63° | — | — |
| 1975 | 73° | 44° | 59° | — | — |
| 1974 | — | 44° | — | — | — |
| 1973 | 68° | 48° | 58° | — | — |
| 1972 | 67° | 48° | 57° | — | — |
| 1971 | 70° | 42° | 56° | — | — |
55 years of data from BURLINGAME