Brentwood, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Brentwood, a city in Contra Costa County, California.
Tonight
60°F
Clear
Clear, with a low around 60. West southwest wind around 5 mph.
7-day forecast for Brentwood
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 60°F | Clear | 5 mph WSW | 0% |
| Saturday | 91°F | Sunny | 2 to 7 mph WNW | 0% |
| Saturday Night | 60°F | Mostly Cloudy | 2 to 6 mph WSW | 0% |
| Sunday | 84°F | Partly Sunny | 2 to 7 mph WSW | 1% |
| Sunday Night | 60°F | Mostly Cloudy | 3 to 7 mph WSW | 1% |
| Monday | 87°F | Sunny | 3 to 8 mph WSW | 0% |
| Monday Night | 60°F | Mostly Clear | 2 to 8 mph WSW | 0% |
| Tuesday | 90°F | Sunny | 2 to 7 mph W | 0% |
| Tuesday Night | 61°F | Clear | 0 to 7 mph WSW | 0% |
| Wednesday | 98°F | Sunny | 0 to 3 mph NNW | 0% |
| Wednesday Night | 66°F | Mostly Clear | 0 to 3 mph NNW | 0% |
| Thursday | 98°F | Sunny | 0 to 7 mph NW | 0% |
| Thursday Night | 66°F | Mostly Clear | 2 to 7 mph WSW | 0% |
| Friday | 92°F | Sunny | 2 to 9 mph WSW | 0% |
Forecast source: National Weather Service (api.weather.gov) for Brentwood (37.936, -121.719). Updated through the day.
Growing snapshot for Brentwood
Last spring frost
Jan 12
First fall frost
Dec 19
Growing season
343 days
Hardiness zone
9b
More local growing data for Brentwood: nearby ZIP 94513 weather · frost dates · planting calendar · California frost dates
Nearby towns & communities
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Contra Costa Centre
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Danville
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Discovery Bay
East Richmond Heights
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Climate data from the nearest NOAA station, Antioch Pumping Plt #3, Ca (5.4 mi from Brentwood). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.