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Diablo, CA Weather & Growing Conditions

This Afternoon
62°F
Light Rain
Rain before 5pm, then a chance of rain and patchy fog. Mostly cloudy. High near 62, with temperatures falling to around 57 in the afternoon. South wind 1 to 6 mph. Chance of precipitation is 80%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 62°F Light Rain 1 to 6 mph S 77%
Tonight 46°F Chance Light Rain then Mostly Cloudy 1 to 5 mph ENE 40%
Wednesday 67°F Sunny 5 mph NNW 1%
Wednesday Night 46°F Partly Cloudy then Patchy Fog 2 mph W 0%
Thursday 72°F Patchy Fog then Sunny 1 to 5 mph NNW 0%
Thursday Night 46°F Mostly Clear 2 mph SW 0%
Friday 74°F Sunny 3 mph N 0%
Friday Night 48°F Clear 2 mph NNE 0%
Saturday 75°F Sunny 3 mph NE 0%
Saturday Night 49°F Mostly Clear 2 mph NNW 0%
Sunday 74°F Mostly Sunny 3 mph WNW 0%
Sunday Night 50°F Partly Cloudy 2 mph WNW 0%
Monday 72°F Partly Sunny 3 mph WSW 1%
Monday Night 49°F Partly Cloudy 0 to 3 mph SW 1%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Diablo, CA

Last spring frost
Mar 8
First fall frost
Dec 22
Growing season
282 days
Hardiness zone
9b

Explore more for Diablo, CA: full frost dates · planting calendar · California frost dates

Climate data from the nearest NOAA station, Mt Diablo Junction, Ca (3 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.