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Knightsen, CA Weather & Growing Conditions

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

This Afternoon
87°F
Sunny
Sunny, with a high near 87. West northwest wind around 9 mph.

7-day forecast for Knightsen

WhenTempForecastWindPrecip
This Afternoon 87°F Sunny 9 mph WNW 0%
Tonight 57°F Clear 2 to 9 mph WSW 0%
Saturday 91°F Sunny 2 to 8 mph WNW 0%
Saturday Night 59°F Partly Cloudy 2 to 7 mph WSW 0%
Sunday 85°F Partly Sunny 3 to 8 mph W 0%
Sunday Night 58°F Mostly Cloudy 3 to 8 mph WSW 0%
Monday 87°F Sunny 3 to 9 mph W 0%
Monday Night 58°F Mostly Clear 2 to 9 mph WSW 0%
Tuesday 90°F Sunny 2 to 8 mph W 0%
Tuesday Night 59°F Clear 0 to 8 mph W 0%
Wednesday 97°F Sunny 0 to 5 mph NW 0%
Wednesday Night 64°F Mostly Clear 0 to 5 mph WNW 0%
Thursday 98°F Sunny 0 to 7 mph WNW 0%
Thursday Night 64°F Mostly Clear 2 to 7 mph W 0%

Forecast source: National Weather Service (api.weather.gov) for Knightsen (37.962, -121.649). Updated through the day.

Growing snapshot for Knightsen

Last spring frost
Jan 12
First fall frost
Dec 19
Growing season
343 days
Hardiness zone
9b

More local growing data for Knightsen: nearby ZIP 94548 weather · frost dates · planting calendar · California frost dates

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Climate data from the nearest NOAA station, Antioch Pumping Plt #3, Ca (5.5 mi from Knightsen). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.