Bethel Island, CA Weather & Growing Conditions

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

Today

101°F

Sunny

Sunny. High near 101, with temperatures falling to around 99 in the afternoon. West northwest wind 7 to 14 mph, with gusts as high as 23 mph.

7-day forecast for Bethel Island

When	Temp	Forecast	Wind	Precip
Today	101°F	Sunny	7 to 14 mph WNW	0%
Tonight	61°F	Clear	7 to 14 mph W	0%
Wednesday	95°F	Sunny	8 to 14 mph WNW	0%
Wednesday Night	61°F	Clear	7 to 14 mph W	0%
Thursday	92°F	Sunny	7 to 15 mph W	0%
Thursday Night	62°F	Clear	7 to 15 mph W	0%
Friday	97°F	Sunny	7 to 14 mph W	0%
Friday Night	64°F	Clear	6 to 14 mph W	0%
Saturday	96°F	Sunny	6 to 14 mph W	0%
Saturday Night	65°F	Mostly Clear	5 to 14 mph W	0%
Sunday	93°F	Sunny	6 to 14 mph W	0%
Sunday Night	62°F	Clear	6 to 14 mph WSW	0%
Monday	87°F	Sunny	7 to 14 mph W	0%
Monday Night	60°F	Mostly Clear	6 to 14 mph W	0%

Forecast source: National Weather Service (api.weather.gov) for Bethel Island (38.028, -121.630). Updated through the day.

Growing snapshot for Bethel Island

Last spring frost

Jan 12

First fall frost

Dec 19

Growing season

343 days

Hardiness zone

More local growing data for Bethel Island: nearby ZIP 94511 weather · frost dates · planting calendar · California frost dates

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Climate data from the nearest NOAA station, Antioch Pumping Plt #3, Ca (7.4 mi from Bethel Island). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.