Weather on March 18
Simi Valley, CA
55 Years of Data
Avg High
70°F
Avg Low
50°F
Warmest
2026
82°F avg
Coldest
2012
45°F avg
About This Date
March 18th in Simi Valley, CA typically brings pleasant spring weather, with average highs around 70°F and lows near 50°F. Over 31 years of records, the warmest March 18th was in 2026 (82°F average), while the coldest was 2012 (45°F) — a 37°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
Planning for March 18th in Simi Valley, CA? Great weather for outdoor activities.
Warming Trend
1.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2026warmest | 90° | 74° | 82° | — | — |
| 2025 | 62° | 42° | 52° | — | — |
| 2024 | 75° | 53° | 64° | — | — |
| 2023 | 69° | 55° | 62° | — | — |
| 2022 | 81° | 60° | 70° | — | — |
| 2021 | 69° | 47° | 58° | — | — |
| 2020 | 61° | 42° | 51° | — | — |
| 2019 | 78° | 57° | 68° | — | — |
| 2018 | 62° | 42° | 52° | — | — |
| 2017 | 76° | 50° | 63° | — | — |
| 2016 | 75° | 50° | 63° | — | — |
| 2015 | 70° | 56° | 63° | — | — |
| 2014 | 74° | 50° | 62° | — | — |
| 2013 | 66° | 46° | 56° | — | — |
| 2012coldest | 52° | 39° | 45° | — | — |
| 2011 | 63° | 43° | 53° | — | — |
| 2010 | 77° | 54° | 65° | — | — |
| 2009 | 82° | 59° | 71° | — | — |
| 2008 | 68° | 45° | 56° | — | — |
| 2007 | 61° | 50° | 55° | — | — |
| 2006 | 57° | 41° | 49° | — | — |
| 2005 | 57° | 46° | 52° | — | — |
| 2004 | 72° | 46° | 59° | — | — |
| 2003 | 64° | 46° | 55° | — | — |
| 2002 | 63° | 39° | 51° | — | — |
| 2001 | 82° | 59° | 71° | — | — |
| 2000 | 76° | 63° | 69° | — | — |
| 1999 | 61° | 45° | 53° | — | — |
| 1998 | 70° | 50° | 60° | — | — |
| 1997 | 88° | 55° | 71° | — | — |
| 1996 | 74° | 50° | 62° | — | — |
31 years of data from SIMI VALLEY CALIFORNIA