Weather on September 1
Simi Valley, CA
55 Years of Data
Avg High
90°F
Avg Low
64°F
Warmest
2022
95°F avg
Coldest
2000
62°F avg
About This Date
September 1st in Simi Valley, CA typically brings hot fall weather, with average highs around 90°F and lows near 64°F — a 26°F daily swing. Over 30 years of records, the warmest September 1st was in 2022 (95°F average), while the coldest was 2000 (62°F) — a 33°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 5.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.3°F warmer on this date compared to 20-30 years ago.
Planning for September 1st in Simi Valley, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
2.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 102° | 72° | 87° | — | — |
| 2024 | 96° | 67° | 81° | — | — |
| 2023 | 79° | 61° | 70° | — | — |
| 2022warmest | 111° | 79° | 95° | — | — |
| 2021 | 77° | 58° | 67° | — | — |
| 2020 | 85° | 55° | 70° | — | — |
| 2019 | 103° | 69° | 86° | — | — |
| 2018 | 88° | 60° | 74° | — | — |
| 2017 | 106° | 83° | 94° | — | — |
| 2016 | 93° | 62° | 78° | — | — |
| 2015 | 86° | 60° | 73° | — | — |
| 2014 | 94° | 64° | 79° | — | — |
| 2013 | 96° | 69° | 83° | — | — |
| 2012 | 84° | 55° | 70° | — | — |
| 2011 | 79° | 50° | 64° | — | — |
| 2010 | 84° | 58° | 71° | — | — |
| 2009 | 100° | 68° | 84° | — | — |
| 2008 | 81° | 61° | 71° | — | — |
| 2007 | 97° | 77° | 87° | — | — |
| 2006 | 88° | 59° | 73° | — | — |
| 2005 | 79° | 57° | 68° | — | — |
| 2004 | 90° | 66° | 78° | — | — |
| 2003 | 81° | 61° | 71° | — | — |
| 2002 | 100° | 73° | 87° | — | — |
| 2001 | 93° | 63° | 78° | — | — |
| 2000coldest | 69° | 56° | 62° | — | — |
| 1999 | 76° | 54° | 65° | — | — |
| 1998 | 104° | 83° | 93° | — | — |
| 1997 | 69° | 67° | 68° | — | — |
| 1996 | 95° | 62° | 79° | — | — |
30 years of data from SIMI VALLEY CALIFORNIA