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Napa, CA Weather & Growing Conditions

Tonight
44°F
Chance Light Rain then Patchy Fog
A chance of rain before 10pm, then patchy fog. Mostly cloudy, with a low around 44. Northeast wind around 5 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Tonight 44°F Chance Light Rain then Patchy Fog 5 mph NE 52%
Wednesday 68°F Patchy Fog then Sunny 2 to 7 mph NNW 1%
Wednesday Night 43°F Areas Of Fog 1 to 5 mph NW 0%
Thursday 71°F Areas Of Fog then Sunny 1 to 5 mph NW 0%
Thursday Night 43°F Patchy Fog then Mostly Clear 0 to 3 mph WNW 0%
Friday 72°F Patchy Fog then Sunny 2 mph SE 0%
Friday Night 44°F Mostly Clear 0 mph 0%
Saturday 73°F Sunny 0 to 5 mph ENE 0%
Saturday Night 45°F Mostly Clear then Patchy Fog 0 mph 0%
Sunday 73°F Areas Of Fog then Mostly Sunny 0 to 3 mph NW 0%
Sunday Night 46°F Mostly Cloudy then Areas Of Fog 0 mph 0%
Monday 71°F Areas Of Fog then Partly Sunny 0 to 5 mph WNW 1%
Monday Night 46°F Areas Of Fog 0 to 5 mph NW 2%
Tuesday 71°F Mostly Sunny 0 to 3 mph WNW 9%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Napa, CA

Last spring frost
Feb 12
First fall frost
Dec 4
Growing season
299 days
Hardiness zone
9b

Explore more for Napa, CA: full frost dates · planting calendar · California frost dates

Climate data from the nearest NOAA station, Napa State Hospital, Ca (2.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.