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Hourly Forecast
Daylight Hours
06:57
Sunrise
19:09
Sunset
Moon
Waxing Crescent
12:48
Moonrise
21:26
Moonset
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Weather in Napa today, September 16, 2026
Napa looks cloudy on September 16, 2026, with grey skies for much of the day. Sunshine stays limited, so the overall tone is muted from the morning onward. Expect a grey start, with morning cloud around 92% by 06:00. Outdoor plans early on should not rely on bright skies.
Expect highs of 23°C and cooler readings close to 12°C. Relative humidity sits between 48% and 97%, reaching its peak around 03:00. Winds stay light, near 6.8 km/h by 17:00, so the day feels still more than breezy.
Expect a more open afternoon, with limited cloud around 54% by 23:00. Residual damp risk should be lower than earlier. Visibility stays generally good near 15.1 km on average, though it can drop toward 12.3 km in thicker cloud or showers. Sunrise is at 06:57 and sunset at 19:09, giving 12 hours 11 minutes of sunlight today.
In short, cloud leads the story in Napa on September 16, 2026; expect limited sun and a peak around 23°C.
Frequently asked questions about weather in Napa
How warm does it get in Napa?
The warmest month in Napa is August, with average high temperatures of 30°C. The average temperature during this period is around 21°C.
How cold does it get in Napa?
The coldest month in Napa 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 Napa?
The wettest month in Napa is January, with an average of 131mm of precipitation.
What is the driest time of year in Napa?
The driest month in Napa is August, with an average of 0mm of precipitation.
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