Harman US

Hillsborough, CA Weather & Growing Conditions

Overnight
55°F
Partly Cloudy
Partly cloudy, with a low around 55. Southwest wind around 3 mph.

7-day forecast

WhenTempForecastWindPrecip
Overnight 55°F Partly Cloudy 3 mph SW 0%
Tuesday 81°F Haze then Sunny 2 to 12 mph SW 0%
Tuesday Night 56°F Mostly Clear 3 to 10 mph SW 1%
Wednesday 81°F Sunny 3 to 10 mph SW 0%
Wednesday Night 58°F Mostly Clear 1 to 10 mph WSW 0%
Thursday 81°F Sunny 1 to 10 mph WSW 0%
Thursday Night 58°F Mostly Clear 1 to 10 mph W 0%
Friday 83°F Sunny 1 to 12 mph W 0%
Friday Night 59°F Mostly Clear 2 to 12 mph W 0%
Saturday 82°F Sunny 2 to 12 mph WSW 0%
Saturday Night 60°F Mostly Clear 7 to 12 mph WSW 0%
Sunday 78°F Sunny 7 to 14 mph WSW 0%
Sunday Night 57°F Mostly Clear 8 to 14 mph WSW 0%
Monday 74°F Sunny 8 to 14 mph WSW 0%

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

Growing snapshot for Hillsborough, CA

Last spring frost
Dec 29
First fall frost
Dec 26
Growing season
365 days
Hardiness zone
10a

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

Climate data from the nearest NOAA station, San Francisco Intl Ap, Ca (3.3 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.