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Hourly Forecast
Daylight Hours
06:41
Sunrise
18:53
Sunset
Moon
Waxing Crescent
11:17
Moonrise
20:46
Moonset
Daily Forecast
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Weather in Altadena tomorrow, September 16, 2026
Expect a mostly clear day in Altadena on September 16, 2026, with sunshine dominating from morning through evening. Cloud should stay limited, so the overall feel remains bright and settled. The morning sky stays heavily clouded, with cover near 100% around 00:00. Grey conditions set the early tone before any later change.
The day peaks near 27°C and cools toward 15°C. Relative humidity sits between 47% and 92%, reaching its peak around 05:00. A lighter breeze peaks around 14:00 near 4.1 km/h.
Through the afternoon skies look more workable, with cloud near 30% around 12:00. Later outdoor plans have a clearer window than the morning may have suggested. Visibility stays generally good near 15.8 km on average, though it can drop toward 14.7 km in thicker cloud or showers. The sun rises at 06:41 and sets at 18:51, for a total of 12 hours 9 minutes of sunlight today.
Overall, Altadena on September 16, 2026 favours outdoor plans under mostly open skies, with a comfortable high near 27°C.
Frequently asked questions about weather in Altadena
How warm does it get in Altadena?
The warmest month in Altadena 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 Altadena?
The coldest month in Altadena is January, with average low temperatures of 7°C. The average temperature during this period is around 11°C.
What is the wettest time of year in Altadena?
The wettest month in Altadena is January, with an average of 89mm of precipitation.
What is the driest time of year in Altadena?
The driest month in Altadena is July, with an average of 1mm of precipitation.
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