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Castaic, CA vs Simi Valley, CA weather comparison

Castaic

CA

Castaic and Simi Valley have remarkably similar climates.

The year at a glance

Averages from 30 years of climate history, 1991-2020

Annual weather statistics for Castaic, CA and Simi Valley, CA
CastaicMetricSimi Valley
288 daysSunny daysclear or partly cloudy skies293 days
15 inPrecipitationper year16 in
42 daysWet daysrain or snow per year33 days
7 inSnowfallper year0 in
86 daysHot daysabove 90 °F94 days
1 daysFreezing nightsat or below 32 °F4 days
57%Humidityaverage relative63%
66 °FAverage temperatureyear round66 °F

Monthly temperatures

Average daily high and low for each month, in °F. The gap between the two lines is what an ordinary day feels like across the year.

CastaicSimi Valley

Daily highs

708090JanMarMayJulSepNovCastaic, Jan: 64 °FCastaic, Feb: 65 °FCastaic, Mar: 71 °FCastaic, Apr: 74 °FCastaic, May: 80 °FCastaic, Jun: 87 °FCastaic, Jul: 94 °FCastaic, Aug: 95 °FCastaic, Sep: 91 °FCastaic, Oct: 81 °FCastaic, Nov: 72 °FCastaic, Dec: 63 °FSimi Valley, Jan: 67 °FSimi Valley, Feb: 68 °FSimi Valley, Mar: 72 °FSimi Valley, Apr: 76 °FSimi Valley, May: 80 °FSimi Valley, Jun: 87 °FSimi Valley, Jul: 93 °FSimi Valley, Aug: 95 °FSimi Valley, Sep: 92 °FSimi Valley, Oct: 83 °FSimi Valley, Nov: 74 °FSimi Valley, Dec: 66 °F

Daily lows

5060JanMarMayJulSepNovCastaic, Jan: 47 °FCastaic, Feb: 45 °FCastaic, Mar: 47 °FCastaic, Apr: 49 °FCastaic, May: 54 °FCastaic, Jun: 57 °FCastaic, Jul: 63 °FCastaic, Aug: 64 °FCastaic, Sep: 62 °FCastaic, Oct: 56 °FCastaic, Nov: 49 °FCastaic, Dec: 44 °FSimi Valley, Jan: 45 °FSimi Valley, Feb: 45 °FSimi Valley, Mar: 47 °FSimi Valley, Apr: 49 °FSimi Valley, May: 54 °FSimi Valley, Jun: 58 °FSimi Valley, Jul: 62 °FSimi Valley, Aug: 63 °FSimi Valley, Sep: 61 °FSimi Valley, Oct: 55 °FSimi Valley, Nov: 48 °FSimi Valley, Dec: 44 °F
View monthly temperatures as a table
Monthly temperatures (°F)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Castaic high646571748087949591817263
Simi Valley high676872768087939592837466
Castaic low474547495457636462564944
Simi Valley low454547495458626361554844

Monthly precipitation

Total rain plus melted snow for each month, in inches. Taller bars mean wetter months.

CastaicSimi Valley
0.02.04.0JanMarMayJulSepNovCastaic, Jan: 3.2 inCastaic, Feb: 3.7 inCastaic, Mar: 2.6 inCastaic, Apr: 1.0 inCastaic, May: 0.5 inCastaic, Jun: 0.1 inCastaic, Jul: 0.1 inCastaic, Aug: 0.0 inCastaic, Sep: 0.2 inCastaic, Oct: 0.7 inCastaic, Nov: 0.8 inCastaic, Dec: 2.2 inSimi Valley, Jan: 3.6 inSimi Valley, Feb: 3.8 inSimi Valley, Mar: 2.6 inSimi Valley, Apr: 0.9 inSimi Valley, May: 0.5 inSimi Valley, Jun: 0.1 inSimi Valley, Jul: 0.1 inSimi Valley, Aug: 0.0 inSimi Valley, Sep: 0.2 inSimi Valley, Oct: 0.8 inSimi Valley, Nov: 0.8 inSimi Valley, Dec: 2.3 in
View monthly precipitation as a table
Monthly precipitation (inches)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Castaic3.23.72.61.00.50.10.10.00.20.70.82.2
Simi Valley3.63.82.60.90.50.10.10.00.20.80.82.3

Monthly sunny days

Days each month with clear or partly cloudy skies, so compare the same month between cities.

CastaicSimi Valley
0102030JanMarMayJulSepNovCastaic, Jan: 19 daysCastaic, Feb: 17 daysCastaic, Mar: 20 daysCastaic, Apr: 22 daysCastaic, May: 24 daysCastaic, Jun: 27 daysCastaic, Jul: 29 daysCastaic, Aug: 30 daysCastaic, Sep: 28 daysCastaic, Oct: 27 daysCastaic, Nov: 24 daysCastaic, Dec: 21 daysSimi Valley, Jan: 20 daysSimi Valley, Feb: 18 daysSimi Valley, Mar: 21 daysSimi Valley, Apr: 24 daysSimi Valley, May: 24 daysSimi Valley, Jun: 27 daysSimi Valley, Jul: 29 daysSimi Valley, Aug: 30 daysSimi Valley, Sep: 29 daysSimi Valley, Oct: 27 daysSimi Valley, Nov: 24 daysSimi Valley, Dec: 22 days
View monthly sunny days as a table
Monthly sunny days (days)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Castaic191720222427293028272421
Simi Valley201821242427293029272422

Keep comparing

Nearby cities and popular picks for each side of this matchup. Any two cities can be compared from the home page.

Castaic vs another city

See the full Castaic, CA climate profile

More California cities

Simi Valley vs another city

See the full Simi Valley, CA climate profile

More California cities

About this data

Every figure on this page is a 30 year average computed from daily climate history for 1991-2020, using each city's own coordinates. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.

Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).