Weather on August 15
Simi Valley, CA
55 Years of Data
Avg High
90°F
Avg Low
64°F
Warmest
2020
93°F avg
Coldest
2002
64°F avg
About This Date
August 15th in Simi Valley, CA typically brings hot summer weather, with average highs around 90°F and lows near 64°F — a 26°F daily swing. Over 30 years of records, the warmest August 15th was in 2020 (93°F average), while the coldest was 2002 (64°F) — a 29°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.
Planning for August 15th in Simi Valley, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
2.7°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 84° | 59° | 72° | — | — |
| 2024 | 94° | 73° | 83° | — | — |
| 2023 | 96° | 69° | 83° | — | — |
| 2022 | 99° | 70° | 84° | — | — |
| 2021 | 96° | 67° | 81° | — | — |
| 2020warmest | 108° | 78° | 93° | — | — |
| 2019 | 102° | 69° | 86° | — | — |
| 2018 | 90° | 63° | 76° | — | — |
| 2017 | 79° | 58° | 68° | — | — |
| 2016 | 102° | 75° | 89° | — | — |
| 2015 | 104° | 80° | 92° | — | — |
| 2014 | 96° | 66° | 81° | — | — |
| 2013 | 99° | 62° | 80° | — | — |
| 2012 | 84° | 63° | 73° | — | — |
| 2011 | 82° | 57° | 70° | — | — |
| 2010 | 81° | 53° | 67° | — | — |
| 2009 | 75° | 57° | 66° | — | — |
| 2008 | 82° | 64° | 73° | — | — |
| 2007 | 81° | 66° | 73° | — | — |
| 2006 | 75° | 54° | 64° | — | — |
| 2005 | 77° | 57° | 67° | — | — |
| 2004 | 79° | 61° | 70° | — | — |
| 2003 | 93° | 64° | 79° | — | — |
| 2002coldest | 73° | 55° | 64° | — | — |
| 2001 | 102° | 66° | 84° | — | — |
| 2000 | 101° | 73° | 87° | — | — |
| 1999 | 88° | 56° | 72° | — | — |
| 1998 | 94° | 65° | 79° | — | — |
| 1997 | 87° | 58° | 72° | — | — |
| 1996 | 105° | 68° | 87° | — | — |
30 years of data from SIMI VALLEY CALIFORNIA