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Alamo, CA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Alamo, a community in Contra Costa County, California.

Today
88°F
Sunny
Sunny. High near 88, with temperatures falling to around 83 in the afternoon. West southwest wind 2 to 7 mph.

7-day forecast for Alamo

WhenTempForecastWindPrecip
Today 88°F Sunny 2 to 7 mph WSW 0%
Tonight 55°F Partly Cloudy 6 mph SSW 0%
Sunday 76°F Mostly Cloudy 6 mph SSW 0%
Sunday Night 55°F Mostly Cloudy 5 to 8 mph SSW 0%
Monday 78°F Mostly Sunny 8 mph SW 0%
Monday Night 55°F Partly Cloudy 7 mph SW 0%
Tuesday 81°F Sunny 6 mph SW 0%
Tuesday Night 55°F Mostly Clear 1 to 6 mph SW 0%
Wednesday 94°F Sunny 0 to 3 mph WSW 0%
Wednesday Night 60°F Mostly Clear 0 to 3 mph W 0%
Thursday 96°F Sunny 0 to 5 mph WNW 0%
Thursday Night 60°F Mostly Clear 1 to 5 mph WSW 0%
Friday 88°F Sunny 6 mph SW 0%
Friday Night 57°F Mostly Clear 6 mph SW 0%

Forecast source: National Weather Service (api.weather.gov) for Alamo (37.855, -122.014). Updated through the day.

Growing snapshot for Alamo

Last spring frost
Mar 8
First fall frost
Dec 22
Growing season
282 days
Hardiness zone
9b

More local growing data for Alamo: nearby ZIP 94507 weather · frost dates · planting calendar · California frost dates

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Climate data from the nearest NOAA station, Mt Diablo Junction, Ca (4.5 mi from Alamo). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.