Brentwood, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Brentwood, a city in Contra Costa County, California.
Overnight
64°F
Clear
Clear. Low around 64, with temperatures rising to around 66 overnight. West northwest wind around 3 mph.
7-day forecast for Brentwood
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 64°F | Clear | 3 mph WNW | 0% |
| Tuesday | 103°F | Sunny | 3 to 12 mph WNW | 0% |
| Tuesday Night | 64°F | Clear | 3 to 10 mph W | 0% |
| Wednesday | 100°F | Sunny | 3 to 10 mph WNW | 0% |
| Wednesday Night | 63°F | Clear | 3 to 10 mph W | 0% |
| Thursday | 98°F | Sunny | 3 to 12 mph W | 0% |
| Thursday Night | 65°F | Clear | 3 to 12 mph W | 0% |
| Friday | 103°F | Sunny | 3 to 10 mph W | 0% |
| Friday Night | 68°F | Clear | 2 to 10 mph WSW | 0% |
| Saturday | 102°F | Sunny | 2 to 10 mph W | 0% |
| Saturday Night | 69°F | Mostly Clear | 3 to 10 mph WSW | 0% |
| Sunday | 98°F | Sunny | 3 to 12 mph WSW | 0% |
| Sunday Night | 64°F | Clear | 5 to 12 mph WSW | 0% |
| Monday | 93°F | Sunny | 5 to 12 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
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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 Aug 4, 2026.