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Rialto, CA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Rialto, a city in San Bernardino County, California.

This Afternoon
83°F
Sunny
Sunny, with a high near 83. Southwest wind around 10 mph.

7-day forecast for Rialto

WhenTempForecastWindPrecip
This Afternoon 83°F Sunny 10 mph SW 1%
Tonight 62°F Mostly Clear 0 to 10 mph W 1%
Saturday 88°F Sunny 0 to 5 mph SW 0%
Saturday Night 65°F Mostly Clear 0 to 5 mph W 0%
Sunday 85°F Mostly Sunny 0 to 5 mph SW 0%
Sunday Night 64°F Mostly Cloudy 0 to 5 mph SW 1%
Monday 81°F Sunny 0 to 5 mph SW 1%
Monday Night 61°F Mostly Clear 0 to 5 mph SW 1%
Tuesday 86°F Sunny 0 to 5 mph W 0%
Tuesday Night 66°F Clear 0 to 5 mph NW 0%
Wednesday 94°F Sunny 0 to 10 mph W 2%
Wednesday Night 69°F Mostly Clear 0 to 5 mph NW 3%
Thursday 94°F Sunny 0 to 5 mph NW 4%
Thursday Night 70°F Mostly Clear 0 to 5 mph NW 2%

Forecast source: National Weather Service (api.weather.gov) for Rialto (34.117, -117.389). Updated through the day.

Growing snapshot for Rialto

Last spring frost
Jan 10
First fall frost
Jan 2
Growing season
365 days
Hardiness zone
10a

More local growing data for Rialto: nearby ZIP 92376 weather · frost dates · planting calendar · California frost dates

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Climate data from the nearest NOAA station, Riverside Citrus Exp, Ca (10 mi from Rialto). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.