Weather on September 1
San Mateo, CA
55 Years of Data
Avg High
75°F
Avg Low
56°F
Warmest
2017
85°F avg
Coldest
1974
60°F avg
About This Date
September 1st in San Mateo, CA typically brings pleasant fall weather, with average highs around 75°F and lows near 56°F. Over 55 years of records, the warmest September 1st was in 2017 (85°F average), while the coldest was 1974 (60°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 2% of September 1st dates historically. The last decade has been 2.8°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.8°F warmer on this date compared to 20-30 years ago.
Planning for September 1st in San Mateo, CA? Great weather for outdoor activities.
Warming Trend
0.5°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 76° | 57° | 66° | — | — |
| 2024 | 72° | 57° | 64° | — | — |
| 2023 | 71° | 60° | 66° | — | — |
| 2022 | 72° | 55° | 63° | — | — |
| 2021 | 71° | 55° | 63° | — | — |
| 2020 | 72° | 58° | 65° | — | — |
| 2019 | 77° | 61° | 69° | — | — |
| 2018 | 68° | 55° | 62° | — | — |
| 2017warmest | 104° | 67° | 85° | — | — |
| 2016 | 68° | 58° | 63° | — | — |
| 2015 | 76° | 59° | 67° | — | — |
| 2014 | 83° | 60° | 71° | — | — |
| 2013 | 74° | 58° | 66° | — | — |
| 2012 | 68° | 53° | 61° | — | — |
| 2011 | 71° | 54° | 62° | — | — |
| 2010 | 92° | 58° | 75° | — | — |
| 2009 | 74° | 57° | 65° | — | — |
| 2008 | 82° | 55° | 69° | — | — |
| 2007 | 81° | 57° | 69° | — | — |
| 2006 | 69° | 55° | 62° | — | — |
| 2005 | 72° | 56° | 64° | — | — |
| 2004 | 72° | 59° | 65° | — | — |
| 2003 | 72° | 54° | 63° | — | — |
| 2002 | 91° | 54° | 72° | — | — |
| 2001 | 71° | 56° | 63° | — | — |
| 2000 | 63° | 59° | 61° | 0.18" | — |
| 1999 | 70° | 51° | 60° | — | — |
| 1998 | 69° | 53° | 61° | — | — |
| 1997 | 73° | 62° | 68° | — | — |
| 1996 | 71° | 52° | 61° | — | — |
| 1995 | 66° | 54° | 60° | — | — |
| 1994 | 67° | 57° | 62° | — | — |
| 1993 | 79° | 60° | 69° | — | — |
| 1992 | 73° | 59° | 66° | — | — |
| 1991 | 74° | 58° | 66° | — | — |
| 1990 | 70° | 58° | 64° | — | — |
| 1989 | 74° | 52° | 63° | — | — |
| 1988 | 69° | 54° | 61° | — | — |
| 1987 | 73° | 59° | 66° | — | — |
| 1986 | 76° | 52° | 64° | — | — |
| 1985 | 73° | 58° | 65° | — | — |
| 1984 | 90° | 56° | 73° | — | — |
| 1983 | 77° | 57° | 67° | — | — |
| 1982 | 76° | 52° | 64° | — | — |
| 1981 | 79° | 49° | 64° | — | — |
| 1980 | 70° | 53° | 61° | — | — |
| 1979 | 79° | 57° | 68° | — | — |
| 1978 | 86° | 55° | 71° | — | — |
| 1977 | 77° | 51° | 64° | — | — |
| 1976 | 76° | 49° | 62° | — | — |
| 1975 | 74° | 53° | 63° | — | — |
| 1974coldest | 68° | 52° | 60° | — | — |
| 1973 | 75° | 50° | 63° | — | — |
| 1972 | 76° | 51° | 63° | — | — |
| 1971 | 74° | 56° | 65° | — | — |
55 years of data from BURLINGAME