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Hourly Forecast
Daylight Hours
06:42
Sunrise
18:55
Sunset
Moon
Waxing Crescent
11:20
Moonrise
20:47
Moonset
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Weather in Castaic tomorrow, September 16, 2026
Plan for bright conditions in Castaic on September 16, 2026, though cloud cover thickens for a spell near 09:00. The day as a whole still leans toward sunshine. Expect a brighter morning, with limited cloud around 35% by 09:00. Conditions start on a settled note.
Temperatures climb from an overnight low near 15°C toward a daytime high of about 29°C. Expect humidity between 44% and 96%, most humid near 01:00. A lighter breeze peaks around 13:00 near 4.5 km/h.
Through the afternoon skies look more workable, with cloud near 8% around 12:00. Later outdoor plans have a clearer window than the morning may have suggested. Horizontal visibility sits around 15.4 km, briefly nearer 13.5 km. The sun rises at 06:43 and sets at 18:53, for a total of 12 hours 9 minutes of sunlight today.
Taken together, settled sunshine in Castaic on September 16, 2026 makes outdoor timing easier, with highs near 29°C.
Frequently asked questions about weather in Castaic
How warm does it get in Castaic?
The warmest month in Castaic is August, with average high temperatures of 32°C. The average temperature during this period is around 25°C.
How cold does it get in Castaic?
The coldest month in Castaic is January, with average low temperatures of 5°C. The average temperature during this period is around 10°C.
What is the wettest time of year in Castaic?
The wettest month in Castaic is January, with an average of 74mm of precipitation.
What is the driest time of year in Castaic?
The driest month in Castaic is July, with an average of 1mm of precipitation.
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