Castaic climate

Castaic Weather in December

NOAA 1991-2020 normals for Newhall 5NW, 11 km from Castaic

Average highs run from 65°F on December 1 to 63°F on December 31, and lows from 45°F to 46°F. Normal precipitation for the month is 2.62 in over about 5 wet days.

December day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Castaic, in °F, with the record for each date.020406080151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

December at a glance

Average high
62°F
Average low
44°F
Precipitation
2.62 in
Record high
75°FDec 15, 2017
Record low
11°FDec 9, 1972
Chance of a freeze
16%
Daylight
10 h 01 min to 9 h 53 min
Cloud cover
43%
Humidity
61%
Dew point
30°F
Wind
8.9 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Dec 165°F45°F71°F 200825°F 196713%0%
Dec 264°F44°F73°F 201325°F 196813%0%
Dec 364°F44°F71°F 202125°F 197114%0%
Dec 464°F44°F74°F 201621°F 198614%0%
Dec 563°F44°F70°F 199317°F 197214%0%
Dec 663°F44°F74°F 197721°F 196014%0%
Dec 763°F44°F72°F 193720°F 195114%0%
Dec 863°F44°F71°F 201513°F 197215%0%
Dec 962°F43°F72°F 201511°F 197215%0%
Dec 1062°F43°F68°F 199513°F 197215%0%
Dec 1162°F43°F68°F 196713°F 197215%0%
Dec 1262°F43°F67°F 195020°F 196715%0%
Dec 1362°F44°F72°F 201712°F 196716%0%
Dec 1462°F44°F65°F 196213°F 196716%0%
Dec 1562°F44°F75°F 201714°F 196716%0%
Dec 1662°F44°F66°F 199821°F 198716%0%
Dec 1762°F44°F69°F 199817°F 196716%0%
Dec 1862°F44°F71°F 200122°F 193516%0%
Dec 1962°F44°F67°F 202519°F 196716%0%
Dec 2062°F44°F70°F 201814°F 196816%0%
Dec 2162°F44°F67°F 202013°F 199016%0%
Dec 2262°F45°F64°F 200511°F 199016%0%
Dec 2362°F45°F65°F 201717°F 199016%0%
Dec 2462°F45°F65°F 201718°F 198716%0%
Dec 2562°F45°F68°F 201718°F 198716%0%
Dec 2662°F45°F67°F 201720°F 196216%0%
Dec 2762°F46°F70°F 201719°F 195416%0%
Dec 2862°F46°F70°F 201721°F 196916%0%
Dec 2962°F46°F72°F 201720°F 197115%0%
Dec 3063°F46°F73°F 201720°F 197115%0%
Dec 3163°F46°F68°F 201320°F 195115%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Castaic, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (PST).

December 1
sunrise 6:43 AM, sunset 4:44 PM
December 31
sunrise 7:01 AM, sunset 4:54 PM

Every day of December: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00046161 (Newhall 5NW), public domain. Records: NOAA GHCN-Daily, station USW00023187, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.