Reliez Valley, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Reliez Valley, a community in Contra Costa County, California.
This Afternoon
86°F
Sunny
Sunny. High near 86, with temperatures falling to around 82 in the afternoon. West southwest wind 5 to 8 mph.
7-day forecast for Reliez Valley
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 86°F | Sunny | 5 to 8 mph WSW | 0% |
| Tonight | 57°F | Partly Cloudy | 10 mph SW | 0% |
| Sunday | 75°F | Partly Sunny | 6 to 9 mph SW | 0% |
| Sunday Night | 57°F | Mostly Cloudy | 12 mph SW | 0% |
| Monday | 76°F | Mostly Sunny | 12 mph SW | 1% |
| Monday Night | 57°F | Partly Cloudy | 12 mph SW | 1% |
| Tuesday | 78°F | Sunny | 5 to 10 mph SW | 0% |
| Tuesday Night | 56°F | Mostly Clear | 3 to 8 mph SW | 0% |
| Wednesday | 92°F | Sunny | 5 mph W | 0% |
| Wednesday Night | 61°F | Mostly Clear | 5 mph WSW | 0% |
| Thursday | 94°F | Sunny | 2 to 6 mph WSW | 0% |
| Thursday Night | 61°F | Mostly Clear | 7 mph WSW | 0% |
| Friday | 86°F | Sunny | 8 mph SW | 0% |
| Friday Night | 59°F | Mostly Clear | 8 mph SW | 0% |
Forecast source: National Weather Service (api.weather.gov) for Reliez Valley (37.940, -122.103). Updated through the day.
Growing snapshot for Reliez Valley
Last spring frost
Jan 7
First fall frost
Dec 19
Growing season
346 days
Hardiness zone
9b
More local growing data for Reliez Valley: nearby ZIP 94523 weather · frost dates · planting calendar · California frost dates
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Climate data from the nearest NOAA station, Concord Wwtp, Ca (2 mi from Reliez Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.