All-time weather records — Rialto, CA
Climate change signal in Rialto
of Rialto's all-time daily heat records were set in the last decade (0 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 | # |
|---|---|---|---|---|
| 1940s | · | · | ||
| 1950s | 37 | 41 | ||
| 1960s | 69 | 205 | ||
| 1970s | 71 | 69 | ||
| 1980s | 50 | 26 | ||
| 1990s | 47 | 19 | ||
| 2000s | 92 | 6 |
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 1956, the latest in 2009. Period of observation: 1948-2009.
Records by month
| Month | Hottest day | Coldest day | Wettest day |
|---|---|---|---|
| January | 97.0°F — Jan 31, 2003 | 24.1°F — Jan 13, 1963 | 3.16 in — Jan 4, 1995 |
| February | 91.9°F — Feb 7, 1963 | 27.0°F — Feb 17, 1956 | 2.34 in — Feb 24, 1969 |
| March | 98.1°F — Mar 12, 2007 | 28.9°F — Mar 1, 1962 | 2.03 in — Mar 17, 1982 |
| April | 104.0°F — Apr 6, 1989 | 33.1°F — Apr 2, 1956 | 1.39 in — Apr 20, 1983 |
| May | 108.0°F — May 29, 1984 | 37.9°F — May 8, 1965 | 0.71 in — May 9, 1977 |
| June | 111.9°F — Jun 16, 1961 | 44.1°F — Jun 2, 1967 | 0.91 in — Jun 5, 1993 |
| July | 117.0°F — Jul 22, 2006 | 48.9°F — Jul 1, 1965 | 0.33 in — Jul 29, 1968 |
| August | 111.9°F — Aug 29, 1998 | 48.9°F — Aug 22, 1968 | 1.18 in — Aug 17, 1977 |
| September | 113.0°F — Sep 2, 2007 | 42.1°F — Sep 20, 1970 | 1.84 in — Sep 11, 1976 |
| October | 108.0°F — Oct 1, 1980 | 32.0°F — Oct 28, 1970 | 1.96 in — Oct 20, 2004 |
| November | 98.1°F — Nov 7, 2006 | 26.1°F — Nov 17, 1958 | 2.48 in — Nov 23, 1965 |
| December | 93.0°F — Dec 4, 1958 | 21.9°F — Dec 23, 1990 | 2.32 in — Dec 6, 1997 |
Click a month to see every daily record for that month in Rialto.