Weather on April 20
San Mateo, CA
55 Years of Data
Avg High
66°F
Avg Low
50°F
Warmest
2009
75°F avg
Coldest
2008
49°F avg
About This Date
April 20th in San Mateo, CA typically brings mild spring weather, with average highs around 66°F and lows near 50°F. Over 55 years of records, the warmest April 20th was in 2009 (75°F average), while the coldest was 2008 (49°F) — a 26°F range across recorded history. Rain or other precipitation has occurred on about 24% of April 20th dates historically, with the wettest April 20th recording 1.75" of rain. The last decade has been 1.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.3°F warmer on this date compared to 20-30 years ago.
Planning for April 20th in San Mateo, CA? Great weather for outdoor activities.
Warming Trend
0.7°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 63° | 49° | 56° | — | — |
| 2024 | 67° | 51° | 59° | — | — |
| 2023 | 66° | 47° | 56° | — | — |
| 2022 | 68° | 52° | 60° | 0.43" | — |
| 2021 | 60° | 53° | 57° | — | — |
| 2020 | 62° | 54° | 58° | — | — |
| 2019 | 60° | 49° | 54° | — | — |
| 2018 | 67° | 49° | 58° | — | — |
| 2017 | 65° | 54° | 59° | — | — |
| 2016 | 75° | 52° | 63° | — | — |
| 2015 | 68° | 53° | 61° | — | — |
| 2014 | 79° | 51° | 65° | — | — |
| 2013 | 73° | 50° | 62° | — | — |
| 2012 | 78° | 55° | 67° | — | — |
| 2011 | 65° | 53° | 59° | 0.05" | — |
| 2010 | 60° | 49° | 54° | 1.12" | — |
| 2009warmest | 91° | 59° | 75° | — | — |
| 2008coldest | 55° | 42° | 49° | — | — |
| 2007 | 61° | 47° | 54° | 0.36" | — |
| 2006 | 61° | 51° | 56° | — | — |
| 2005 | 62° | 49° | 55° | — | — |
| 2004 | 65° | 55° | 60° | 0.05" | — |
| 2003 | 60° | 51° | 56° | — | — |
| 2002 | 60° | 48° | 54° | — | — |
| 2001 | 57° | 46° | 52° | 1.75" | — |
| 2000 | 66° | 52° | 59° | — | — |
| 1999 | 59° | 49° | 54° | — | — |
| 1998 | 68° | 52° | 60° | — | — |
| 1997 | 71° | 57° | 64° | — | — |
| 1996 | 61° | 45° | 53° | — | — |
| 1995 | 57° | 46° | 52° | 0.08" | — |
| 1994 | 62° | 51° | 57° | — | — |
| 1993 | 71° | 50° | 61° | — | — |
| 1992 | 69° | 55° | 62° | — | — |
| 1991 | 64° | 50° | 57° | 1.14" | — |
| 1990 | 65° | 52° | 58° | — | — |
| 1989 | 69° | 51° | 60° | — | — |
| 1988 | 63° | 50° | 56° | 0.15" | — |
| 1987 | 79° | 48° | 63° | — | — |
| 1986 | 81° | 53° | 67° | — | — |
| 1985 | 57° | 47° | 52° | 0.28" | — |
| 1984 | 64° | 45° | 54° | — | — |
| 1983 | 62° | 53° | 58° | — | — |
| 1982 | 75° | 49° | 62° | — | — |
| 1981 | 65° | 49° | 57° | — | — |
| 1980 | 63° | 46° | 54° | 0.23" | — |
| 1979 | 61° | 42° | 51° | — | — |
| 1978 | 61° | 49° | 55° | 0.64" | — |
| 1977 | 76° | 39° | 57° | — | — |
| 1976 | 74° | 47° | 60° | — | — |
| 1975 | 62° | 41° | 52° | — | — |
| 1974 | 64° | 47° | 55° | — | — |
| 1973 | 66° | 49° | 57° | — | — |
| 1972 | 62° | 47° | 54° | — | — |
| 1971 | 55° | 46° | 51° | 0.08" | — |
55 years of data from BURLINGAME