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Hourly Forecast
Daylight Hours
06:58
Sunrise
19:12
Sunset
Moon
Waxing Crescent
11:47
Moonrise
20:55
Moonset
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Weather in Petaluma today, September 15, 2026
Petaluma sees a largely clear day on September 15, 2026, interrupted by cloudier skies around 23:00. Plan for bright conditions either side of that cloudier interval. The morning looks comparatively open, with cloud near 0% around 05:00. Early outdoor plans have a better chance of staying dry and bright.
Expect highs of 29°C and cooler readings close to 10°C. The air stays humid, with relative humidity between 31% and 84% and the peak around 05:00. A lighter breeze peaks around 17:00 near 5.3 km/h.
Through the afternoon skies look more workable, with cloud near 26% around 23:00. Later outdoor plans have a clearer window than the morning may have suggested. Horizontal visibility holds close to 16.1 km. The sun rises at 06:58 and sets at 19:12, for a total of 12 hours 13 minutes of sunlight today.
In short, September 15, 2026 looks like a fine day in Petaluma for being outside, peaking around 29°C.
Frequently asked questions about weather in Petaluma
How warm does it get in Petaluma?
The warmest month in Petaluma is August, with average high temperatures of 25°C. The average temperature during this period is around 18°C.
How cold does it get in Petaluma?
The coldest month in Petaluma is December, with average low temperatures of 6°C. The average temperature during this period is around 10°C.
What is the wettest time of year in Petaluma?
The wettest month in Petaluma is January, with an average of 151mm of precipitation.
What is the driest time of year in Petaluma?
The driest month in Petaluma is July, with an average of 0mm of precipitation.
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