Weather on September 15
Hayward, CA
55 Years of Data
Avg High
73°F
Avg Low
56°F
Warmest
1971
85°F avg
Coldest
1973
57°F avg
About This Date
September 15th in Hayward, CA typically brings pleasant fall weather, with average highs around 73°F and lows near 56°F. Over 53 years of records, the warmest September 15th was in 1971 (85°F average), while the coldest was 1973 (57°F) — a 28°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 2.5°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.5°F warmer on this date compared to 20-30 years ago.
Planning for September 15th in Hayward, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 86° | 59° | 73° | — | — |
| 2024 | 68° | 59° | 64° | — | — |
| 2023 | 74° | 64° | 69° | — | — |
| 2022 | 70° | 61° | 65° | — | — |
| 2021 | 73° | 57° | 65° | — | — |
| 2020 | 77° | 60° | 69° | — | — |
| 2019 | 72° | 60° | 66° | — | — |
| 2018 | 69° | 58° | 63° | — | — |
| 2017 | 73° | 59° | 66° | — | — |
| 2016 | 71° | 56° | 63° | — | — |
| 2015 | 68° | 58° | 63° | — | — |
| 2014 | 80° | 63° | 71° | — | — |
| 2013 | 72° | 58° | 65° | — | — |
| 2012 | 70° | 55° | 62° | — | — |
| 2011 | 67° | 58° | 62° | — | — |
| 2010 | 66° | 55° | 61° | — | — |
| 2009 | 78° | 60° | 69° | — | — |
| 2008 | 71° | 57° | 64° | — | — |
| 2007 | 71° | 59° | 65° | — | — |
| 2006 | 67° | 53° | 60° | — | — |
| 2005 | 66° | 55° | 61° | — | — |
| 2004 | 87° | 60° | 74° | — | — |
| 2003 | 75° | 58° | 66° | — | — |
| 2002 | 70° | 59° | 64° | — | — |
| 2001 | 66° | 55° | 61° | — | — |
| 2000 | 69° | 60° | 65° | — | — |
| 1999 | 68° | 56° | 62° | — | — |
| 1998 | 70° | 55° | 62° | — | — |
| 1997 | 73° | 53° | 63° | — | — |
| 1996 | 67° | 54° | 60° | — | — |
| 1995 | 67° | 54° | 60° | — | — |
| 1994 | 91° | 63° | 77° | — | — |
| 1993 | 64° | 52° | 58° | — | — |
| 1992 | 72° | 51° | 61° | — | — |
| 1989 | 80° | 53° | 67° | — | — |
| 1988 | 70° | 50° | 60° | — | — |
| 1987 | 75° | 56° | 65° | — | — |
| 1986 | 70° | 56° | 63° | — | — |
| 1985 | 71° | 51° | 61° | — | — |
| 1984 | 83° | 58° | 70° | — | — |
| 1983 | 90° | 60° | 75° | — | — |
| 1982 | 70° | 57° | 63° | — | — |
| 1981 | 70° | 57° | 63° | — | — |
| 1980 | 68° | 53° | 61° | — | — |
| 1979 | 84° | 58° | 71° | — | — |
| 1978 | 79° | 54° | 66° | — | — |
| 1977 | 68° | 57° | 63° | — | — |
| 1976 | 70° | 53° | 61° | — | — |
| 1975 | 68° | 50° | 59° | — | — |
| 1974 | 72° | 53° | 62° | — | — |
| 1973coldest | 66° | 49° | 57° | — | — |
| 1972 | 71° | 49° | 60° | — | — |
| 1971warmest | 104° | 66° | 85° | — | — |
53 years of data from HAYWARD AIR TERMINAL