Climate averages 1991–2020
Simi Valley weather
in April.
A mild, fairly dry month: the 7th warmest and the 8th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
April is a mild month in Simi Valley: daytime highs average 21.7°C and nights cool to about 9.7°C. By daytime temperature it is the 7th warmest of the 12 months.
Expect about 22 mm of rain on roughly 3 days, which makes April a fairly dry month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 01 min on an average April day.
The nearest other city in this atlas is Thousand Oaks (12 km away). In April its highs average 20.9°C, 0.8°C cooler than Simi Valley, with 22 mm of rain.
Among the 498 cities listed in the United States, Simi Valley ranks joint 170th of 498 for the warmest April highs and joint 52nd of 498 for the driest April (rainfall, lowest first). The mean April high of those 498 cities is 19.4°C; Simi Valley is 2.4°C warmer than that mean.
From April to May, average highs rise by 2.1°C to 23.9°C, and monthly rainfall falls from 22 mm to 12 mm.
The annual picture
April in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Simi Valley climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 17.7°C6.0°C | 6.0°C | 91 | 5.6 | 10.110 h |
| February | 17.8°C6.4°C | 6.4°C | 98 | 6.4 | 10.911 h |
| March | 19.5°C7.9°C | 7.9°C | 66 | 5.6 | 11.912 h |
| April, selected | 21.7°C9.7°C | 9.7°C | 22 | 2.9 | 13.013 h |
| May | 23.9°C12.7°C | 12.7°C | 12 | 1.8 | 13.914 h |
| June | 26.8°C15.6°C | 15.6°C | 2.0 | 0.5 | 14.414 h |
| July | 29.6°C18.7°C | 18.7°C | 3.1 | 0.5 | 14.214 h |
| August | 30.7°C19.3°C | 19.3°C | 0.3 | 0.1 | 13.413 h |
| September | 29.5°C17.6°C | 17.6°C | 3.9 | 0.6 | 12.412 h |
| October | 25.8°C13.7°C | 13.7°C | 20 | 2.1 | 11.411 h |
| November | 21.5°C9.2°C | 9.2°C | 21 | 2.6 | 10.410 h |
| December | 17.4°C5.9°C | 5.9°C | 58 | 4.8 | 9.910 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
April in nearby cities
- Thousand Oaks in AprilUnited States · 12 kmHigh 20.9°C · Low 10.0°C · 22 mm rain
- Valencia, United States in AprilUnited States · 25 kmHigh 22.7°C · Low 9.2°C · 21 mm rain
- Santa Clarita in AprilUnited States · 26 kmHigh 22.3°C · Low 9.1°C · 21 mm rain
- Oxnard in AprilUnited States · 37 kmHigh 18.6°C · Low 11.0°C · 22 mm rain
- Burbank in AprilUnited States · 45 kmHigh 23.4°C · Low 10.3°C · 24 mm rain
- Ventura in AprilUnited States · 47 kmHigh 20.0°C · Low 10.3°C · 22 mm rain
- Glendale (California), United States in AprilUnited States · 50 kmHigh 22.6°C · Low 9.7°C · 24 mm rain
- Inglewood in AprilUnited States · 52 kmHigh 22.1°C · Low 10.6°C · 19 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Simi Valley) is explained once on the Simi Valley year overview and on the Sources, method and limits page.
Thousand Oaks lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.