All-time weather records — San Marino, CA
Climate change signal in San Marino
of San Marino's all-time daily heat records were set in the last decade (63 of 366 records since 2015).
of all-time daily cold records were set in the last decade (0 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 | # |
|---|---|---|---|---|
| 1890s | · | 16 | ||
| 1900s | 5 | 27 | ||
| 1910s | 37 | 170 | ||
| 1920s | 20 | 66 | ||
| 1930s | 26 | 36 | ||
| 1940s | 19 | 15 | ||
| 1950s | 26 | 8 | ||
| 1960s | 24 | 5 | ||
| 1970s | 33 | 9 | ||
| 1980s | 33 | 7 | ||
| 1990s | 38 | 7 | ||
| 2000s | 28 | · | ||
| 2010s | 45 | · | ||
| 2020s | 32 | · |
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 1909, the latest in 2026. Period of observation: 1893-2026.
Records by month
| Month | Hottest day | Coldest day | Wettest day |
|---|---|---|---|
| January | 93.0°F — Jan 18, 1971 | 21.0°F — Jan 7, 1913 | 7.08 in — Jan 22, 1943 |
| February | 96.1°F — Feb 27, 2026 | 26.1°F — Feb 9, 1929 | 6.25 in — Feb 24, 1913 |
| March | 99.0°F — Mar 17, 2026 | 23.0°F — Mar 2, 1978 | 7.70 in — Mar 2, 1938 |
| April | 105.1°F — Apr 6, 1989 | 30.9°F — Apr 18, 1917 | 3.81 in — Apr 5, 1926 |
| May | 104.0°F — May 15, 2014 | 32.0°F — May 1, 1915 | 1.82 in — May 9, 1977 |
| June | 113.0°F — Jun 17, 1917 | 41.0°F — Jun 1, 1916 | 1.58 in — Jun 16, 1995 |
| July | 113.0°F — Jul 7, 2018 | 45.0°F — Jul 7, 1894 | 0.45 in — Jul 1, 1918 |
| August | 109.0°F — Aug 18, 2020 | 43.0°F — Aug 28, 1912 | 3.41 in — Aug 21, 2023 |
| September | 115.0°F — Sep 6, 2020 | 41.0°F — Sep 27, 1911 | 4.90 in — Sep 25, 1939 |
| October | 108.0°F — Oct 11, 1991 | 36.0°F — Oct 20, 1920 | 5.14 in — Oct 20, 2004 |
| November | 100.9°F — Nov 4, 2010 | 26.1°F — Nov 28, 1919 | 5.55 in — Nov 29, 1970 |
| December | 93.0°F — Dec 3, 1958 | 25.0°F — Dec 27, 1916 | 6.17 in — Dec 31, 1933 |
Click a month to see every daily record for that month in San Marino.