Weather on September 21
Corona, CA
55 Years of Data
Avg High
88°F
Avg Low
57°F
Warmest
2003
81°F avg
Coldest
1986
61°F avg
About This Date
September 21st in Corona, CA typically brings warm fall weather, with average highs around 88°F and lows near 57°F — a 31°F daily swing. Over 45 years of records, the warmest September 21st was in 2003 (81°F average), while the coldest was 1986 (61°F) — a 20°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 4.1°F cooler on this date compared to 20-30 years ago.
The last decade has been 4.1°F cooler on this date compared to 20-30 years ago.
Planning for September 21st in Corona, CA? Stay hydrated and seek shade during peak afternoon hours.
Cooling Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 82° | 56° | 69° | — | — |
| 2024 | 80° | 53° | 67° | — | — |
| 2023 | 76° | 55° | 65° | — | — |
| 2022 | 85° | 56° | 70° | — | — |
| 2021 | 102° | 55° | 79° | — | — |
| 2020 | 88° | 60° | 74° | — | — |
| 2019 | 94° | 52° | 73° | — | — |
| 2018 | 86° | 53° | 70° | — | — |
| 2017 | 73° | 50° | 62° | — | — |
| 2016 | 88° | 62° | 75° | — | — |
| 2015 | 89° | 64° | 77° | — | — |
| 2014 | 83° | 58° | 70° | — | — |
| 2013 | 79° | 56° | 67° | — | — |
| 2012 | 98° | 56° | 77° | — | — |
| 2011 | 88° | 60° | 74° | — | — |
| 2010 | 78° | 59° | 69° | — | — |
| 2009 | 93° | 59° | 76° | — | — |
| 2008 | 81° | 57° | 69° | — | — |
| 2007 | 81° | 53° | 67° | — | — |
| 2006 | 84° | 51° | 68° | — | — |
| 2005 | 90° | 59° | 74° | — | — |
| 2004 | 88° | 60° | 74° | — | — |
| 2003warmest | 102° | 59° | 81° | — | — |
| 2002 | 97° | 59° | 78° | — | — |
| 2001 | 93° | 57° | 75° | — | — |
| 2000 | 72° | 64° | 68° | — | — |
| 1999 | 96° | 59° | 78° | — | — |
| 1998 | 74° | 62° | 68° | — | — |
| 1987 | 94° | 58° | 76° | — | — |
| 1986coldest | 79° | 43° | 61° | — | — |
| 1985 | 95° | 55° | 75° | — | — |
| 1984 | 91° | 63° | 77° | — | — |
| 1983 | 93° | 66° | 80° | — | — |
| 1982 | 96° | 54° | 75° | — | — |
| 1981 | 91° | 57° | 74° | — | — |
| 1980 | 80° | 56° | 68° | — | — |
| 1979 | 96° | 56° | 76° | — | — |
| 1978 | 94° | 48° | 71° | — | — |
| 1977 | 86° | 52° | 69° | — | — |
| 1976 | 80° | 64° | 72° | — | — |
| 1975 | 95° | 55° | 75° | — | — |
| 1974 | 99° | 57° | 78° | — | — |
| 1973 | 82° | 50° | 66° | — | — |
| 1972 | 98° | 53° | 76° | — | — |
| 1971 | 80° | 61° | 70° | — | — |
45 years of data from CORONA CALIFORNIA