Brentwood, CA Weather & Growing Conditions
Overnight
50°F
Partly Cloudy
Partly cloudy, with a low around 50. Northwest wind around 5 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 50°F | Partly Cloudy | 5 mph NW | 0% |
| Wednesday | 69°F | Sunny | 3 to 8 mph NW | 1% |
| Wednesday Night | 50°F | Mostly Cloudy | 3 mph W | 1% |
| Thursday | 73°F | Mostly Sunny | 2 to 7 mph NW | 0% |
| Thursday Night | 48°F | Clear | 3 mph W | 0% |
| Friday | 72°F | Sunny | 0 to 5 mph NNW | 0% |
| Friday Night | 49°F | Mostly Clear | 0 mph | 0% |
| Saturday | 74°F | Sunny | 0 to 3 mph NNE | 0% |
| Saturday Night | 50°F | Mostly Clear | 1 mph NW | 0% |
| Sunday | 73°F | Sunny | 1 to 5 mph NW | 0% |
| Sunday Night | 51°F | Partly Cloudy | 1 mph NNW | 0% |
| Monday | 73°F | Mostly Sunny | 0 to 3 mph WNW | 0% |
| Monday Night | 50°F | Partly Cloudy | 0 to 3 mph W | 1% |
| Tuesday | 73°F | Sunny | 2 mph WNW | 5% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Brentwood, CA
Last spring frost
Jan 12
First fall frost
Dec 19
Growing season
343 days
Hardiness zone
9b
Explore more for Brentwood, CA: full frost dates · planting calendar · California frost dates
Climate data from the nearest NOAA station, Antioch Pumping Plt #3, Ca (5.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.