Clayton, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Clayton, a city in Contra Costa County, California.
Today
63°F
Light Rain
Rain. Mostly cloudy. High near 63, with temperatures falling to around 57 in the afternoon. South southwest wind 3 to 8 mph. Chance of precipitation is 80%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Clayton
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 63°F | Light Rain | 3 to 8 mph SSW | 78% |
| Tonight | 47°F | Chance Light Rain then Mostly Cloudy | 2 mph E | 41% |
| Wednesday | 68°F | Sunny | 2 to 7 mph NNW | 1% |
| Wednesday Night | 47°F | Partly Cloudy | 1 to 5 mph WSW | 0% |
| Thursday | 72°F | Sunny | 1 to 6 mph WNW | 0% |
| Thursday Night | 48°F | Mostly Clear | 0 to 3 mph WSW | 0% |
| Friday | 74°F | Sunny | 0 to 5 mph NNW | 0% |
| Friday Night | 48°F | Clear | 1 mph NNW | 0% |
| Saturday | 74°F | Sunny | 0 to 6 mph NE | 0% |
| Saturday Night | 49°F | Mostly Clear | 1 mph NW | 0% |
| Sunday | 74°F | Mostly Sunny | 0 to 5 mph NW | 0% |
| Sunday Night | 50°F | Partly Cloudy | 1 mph W | 0% |
| Monday | 72°F | Partly Sunny | 1 to 6 mph WSW | 1% |
| Monday Night | 49°F | Partly Cloudy | 0 to 3 mph WSW | 1% |
Forecast source: National Weather Service (api.weather.gov) for Clayton (37.940, -121.930). Updated through the day.
Growing snapshot for Clayton
Last spring frost
Jan 9
First fall frost
Dec 14
Growing season
343 days
Hardiness zone
9b
More local growing data for Clayton: nearby ZIP 94521 weather · frost dates · planting calendar · California frost dates
Nearby towns & communities
Acalanes Ridge
Alamo
Alhambra Valley
Antioch
Bay Point
Bayview
Benicia
Bethel Island
Blackhawk
Brentwood
Byron
Castle Hill
Clyde
Concord
Contra Costa Centre
Crockett
Danville
Diablo
Discovery Bay
East Richmond Heights
El Cerrito
El Sobrante
Hercules
Knightsen
Lafayette
Martinez
Montalvin Manor
Moraga
Mountain View
Norris Canyon
Climate data from the nearest NOAA station, Concord Buchanan Fld, Ca (5.4 mi from Clayton). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.