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Walnut, CA Weather & Growing Conditions

Overnight
61°F
Mostly Clear
Mostly clear, with a low around 61. South southeast wind around 5 mph.

7-day forecast

WhenTempForecastWindPrecip
Overnight 61°F Mostly Clear 5 mph SSE 0%
Saturday 85°F Sunny 5 to 10 mph SSW 0%
Saturday Night 62°F Patchy Fog 5 mph SSW 0%
Sunday 82°F Patchy Fog then Partly Sunny 5 to 10 mph SSW 0%
Sunday Night 63°F Patchy Fog 5 mph SSW 2%
Monday 79°F Mostly Sunny 5 to 10 mph SSW 1%
Monday Night 61°F Partly Cloudy 0 to 10 mph SSW 1%
Tuesday 82°F Sunny 0 to 10 mph SSW 0%
Tuesday Night 63°F Mostly Clear 0 to 10 mph WSW 0%
Wednesday 88°F Sunny 0 to 10 mph SW 0%
Wednesday Night 64°F Mostly Clear 0 to 10 mph SSW 0%
Thursday 89°F Sunny 0 to 10 mph SSW 3%
Thursday Night 65°F Mostly Clear 0 to 10 mph SW 3%
Friday 89°F Sunny 0 to 10 mph SW 3%

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

Growing snapshot for Walnut, CA

Last spring frost
Jan 8
First fall frost
Dec 28
Growing season
354 days
Hardiness zone
10a

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

Climate data from the nearest NOAA station, Pomona/Fairplex, Ca (6.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.