Weather on October 31
San Mateo, CA
55 Years of Data
Avg High
68°F
Avg Low
50°F
Warmest
1983
65°F avg
Coldest
1971
50°F avg
About This Date
October 31st in San Mateo, CA typically brings mild fall weather, with average highs around 68°F and lows near 50°F. Over 55 years of records, the warmest October 31st was in 1983 (65°F average), while the coldest was 1971 (50°F) — a 15°F range across recorded history. Rain or other precipitation has occurred on about 16% of October 31st dates historically, with the wettest October 31st recording 0.76" of rain. The last decade has been 1.9°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.9°F warmer on this date compared to 20-30 years ago.
Planning for October 31st in San Mateo, CA? Great weather for outdoor activities.
Warming Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 68° | 52° | 60° | — | — |
| 2024 | 65° | 51° | 58° | 0.03" | — |
| 2023 | 74° | 50° | 62° | — | — |
| 2022 | 64° | 50° | 57° | — | — |
| 2021 | 63° | 56° | 59° | — | — |
| 2020 | 76° | 47° | 61° | — | — |
| 2019 | 73° | 49° | 61° | — | — |
| 2018 | 76° | 50° | 63° | — | — |
| 2017 | 66° | 52° | 59° | — | — |
| 2016 | 66° | 54° | 60° | 0.08" | — |
| 2015 | 73° | 55° | 64° | — | — |
| 2014 | 64° | 58° | 61° | 0.46" | — |
| 2013 | 70° | 48° | 59° | — | — |
| 2012 | 64° | 57° | 61° | 0.13" | — |
| 2011 | 71° | 53° | 62° | — | — |
| 2010 | 66° | 51° | 59° | — | — |
| 2009 | 69° | 52° | 60° | — | — |
| 2008 | 71° | 59° | 65° | 0.38" | — |
| 2007 | 61° | 52° | 56° | — | — |
| 2006 | 60° | 50° | 55° | — | — |
| 2005 | 72° | 49° | 60° | — | — |
| 2004 | 69° | 53° | 61° | — | — |
| 2003 | 57° | 48° | 53° | — | — |
| 2002 | 67° | 43° | 55° | — | — |
| 2001 | 66° | 52° | 59° | — | — |
| 2000 | 67° | 47° | 57° | — | — |
| 1999 | 76° | 49° | 62° | — | — |
| 1998 | 63° | 45° | 54° | — | — |
| 1997 | 71° | 57° | 64° | — | — |
| 1996 | 62° | 50° | 56° | — | — |
| 1995 | 67° | 56° | 61° | 0.08" | — |
| 1994 | 74° | 46° | 60° | — | — |
| 1993 | 68° | 53° | 61° | — | — |
| 1992 | 70° | 54° | 62° | — | — |
| 1991 | 67° | 45° | 56° | — | — |
| 1990 | 63° | 52° | 57° | 0.48" | — |
| 1989 | 69° | 47° | 58° | — | — |
| 1988 | 76° | 50° | 63° | — | — |
| 1987 | 69° | 57° | 63° | — | — |
| 1986 | 71° | 49° | 60° | — | — |
| 1985 | 65° | 47° | 56° | — | — |
| 1984 | 65° | 45° | 55° | — | — |
| 1983warmest | 70° | 60° | 65° | — | — |
| 1982 | 69° | 46° | 58° | — | — |
| 1981 | 70° | 52° | 61° | — | — |
| 1980 | 74° | 48° | 61° | — | — |
| 1979 | 64° | 52° | 58° | — | — |
| 1978 | 65° | 47° | 56° | — | — |
| 1977 | 66° | 46° | 56° | — | — |
| 1976 | 75° | 48° | 62° | — | — |
| 1975 | 67° | 44° | 55° | — | — |
| 1974 | 62° | 48° | 55° | 0.76" | — |
| 1973 | 76° | 51° | 63° | — | — |
| 1972 | 68° | 57° | 63° | — | — |
| 1971coldest | 62° | 37° | 50° | 0.03" | — |
55 years of data from BURLINGAME