Harman US

Fontana, CA Weather & Growing Conditions

This Afternoon
87°F
Sunny
Sunny, with a high near 87. Southwest wind around 10 mph, with gusts as high as 20 mph.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 87°F Sunny 10 mph SW 0%
Tonight 65°F Partly Cloudy 0 to 10 mph W 0%
Sunday 85°F Mostly Sunny 0 to 10 mph W 0%
Sunday Night 64°F Partly Cloudy 5 to 10 mph SW 2%
Monday 80°F Sunny 0 to 10 mph SW 2%
Monday Night 62°F Mostly Clear 0 to 10 mph W 1%
Tuesday 83°F Sunny 0 to 5 mph SW 0%
Tuesday Night 65°F Clear 0 to 5 mph W 0%
Wednesday 92°F Sunny 0 to 10 mph W 0%
Wednesday Night 68°F Clear 0 to 10 mph NW 1%
Thursday 94°F Sunny 0 to 10 mph W 2%
Thursday Night 69°F Mostly Clear 0 to 10 mph W 1%
Friday 91°F Sunny 0 to 5 mph SW 3%
Friday Night 68°F Mostly Clear 0 to 5 mph W 1%

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

Growing snapshot for Fontana, CA

Last spring frost
Jan 4
First fall frost
Dec 30
Growing season
365 days
Hardiness zone
10a

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

Climate data from the nearest NOAA station, Ontario Intl Ap, Ca (8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.