All-time weather records — San Mateo, CA

Record high
106.0°F
June 14, 1961
Record low
24.1°F
December 9, 1972
Wettest day
5.59 in
January 4, 1982

Climate change signal in San Mateo

19.9%

of San Mateo's all-time daily heat records were set in the last decade (73 of 366 records since 2015).

0.3%

of all-time daily cold records were set in the last decade (1 of 366 records since 2015).

If records were spread evenly across the station's history, you'd expect roughly 5% per decade. Decade-by-decade, here's where each record-breaking day was set:

Decade Heat records set # Cold records set #
1940s
14
94
1950s
56
166
1960s
33
55
1970s
39
33
1980s
51
9
1990s
33
5
2000s
45
2
2010s
54
2
2020s
41
·

Records are the all-time daily extremes that are still standing — each daily record can only be held by one year. The station's earliest hot record was set in 1945, the latest in 2026. Period of observation: 1945-2026.

Records by month

Month Hottest day Coldest day Wettest day
January 73.9°F — Jan 17, 2021 26.1°F — Jan 5, 1949 5.59 in — Jan 4, 1982
February 78.1°F — Feb 10, 2022 30.0°F — Feb 1, 1950 2.92 in — Feb 2, 1998
March 89.1°F — Mar 20, 2026 30.9°F — Mar 3, 1966 1.99 in — Mar 8, 1978
April 91.9°F — Apr 8, 1989 36.0°F — Apr 27, 1955 2.30 in — Apr 2, 1958
May 97.0°F — May 27, 1984 39.0°F — May 3, 1950 1.53 in — May 20, 1957
June 106.0°F — Jun 14, 1961 43.0°F — Jun 1, 1954 0.81 in — Jun 2, 1967
July 105.1°F — Jul 17, 1988 44.1°F — Jul 29, 1951 0.35 in — Jul 2, 1977
August 100.0°F — Aug 1, 1993 45.0°F — Aug 3, 1954 0.56 in — Aug 19, 1997
September 104.0°F — Sep 1, 2017 41.0°F — Sep 30, 1950 2.29 in — Sep 18, 1959
October 99.0°F — Oct 5, 1987 37.0°F — Oct 20, 1949 4.02 in — Oct 24, 2021
November 84.9°F — Nov 1, 1967 30.9°F — Nov 30, 1954 2.55 in — Nov 22, 2024
December 75.0°F — Dec 2, 1958 24.1°F — Dec 9, 1972 3.67 in — Dec 31, 2022

Click a month to see every daily record for that month in San Mateo.