Frost Dates for Foster City, CA

Based on data from Redwood City weather station, 6 miles away

Elevation: 7 ft

Frost Dates

Last Spring Frost (50%) A 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide. January 17
First Fall Frost (50%) A 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date. December 12

30% Probability

Only a 30% chance of frost remaining by this date. Use these dates for a safer planting window, especially for tender plants sensitive to cold.
Last Spring Frost January 31
First Fall Frost December 4

Hard Freeze (28°F)

Last Spring Hard Freeze December 31
First Fall Hard Freeze December 26
37.56°N, 122.27°W © OpenStreetMap

Growing Season

330 Days January 17 to December 12

USDA Hardiness Zone

Hardiness zones indicate which perennial plants can survive winter in your area. For annual vegetables, frost dates and growing season length matter more than hardiness zone.
Zone 9b

Avg. annual minimum: 25 to 30°F

Learn more

Köppen Climate

The Köppen climate classification system categorizes climates based on temperature and precipitation patterns.
Csb Warm-Summer Mediterranean

Warm, dry summers and mild, wet winters. Similar to hot-summer Mediterranean but cooler. Great for a wide range of vegetables and fruit trees with moderate water needs.

Köppen climate map

Temperature

Avg High Avg Temp Avg Low
Temperature table
Average monthly temperatures (°F)
Month Avg High Avg Temp Avg Low
January59°50°41°
February62°52°43°
March65°55°45°
April69°58°47°
May73°62°50°
June79°66°54°
July81°69°57°
August81°69°57°
September79°67°54°
October75°62°50°
November65°54°44°
December59°49°40°

Precipitation

Precipitation table
Average monthly precipitation (inches)
MonthPrecipitation
January6.7
February6.5
March5.9
April3.9
May0.8
June0.0
July0.0
August0.0
September0.0
October1.2
November4.8
December6.5

Sunrise / Sunset

Daylight Pacific Time (PT) Longest: 14h 35m · Shortest: 9h 25m
Sunrise and sunset table
Sunrise, sunset, and daylight on the 15th of each month (Pacific Time (PT))
Month Sunrise Sunset Daylight
January7:28 AM5:09 PM9h 41m
February7:05 AM5:42 PM10h 37m
March7:27 AM7:10 PM11h 43m
April6:40 AM7:38 PM12h 58m
May6:05 AM8:06 PM14h 01m
June5:52 AM8:26 PM14h 34m
July6:04 AM8:25 PM14h 21m
August6:30 AM7:56 PM13h 27m
September6:57 AM7:10 PM12h 14m
October7:24 AM6:24 PM11h 00m
November6:56 AM4:52 PM9h 56m
December7:22 AM4:48 PM9h 25m

Nearby Stations

Woodside Fire Stn 1, CA February 25 - November 25 Palo Alto, CA February 1 - December 7 Half Moon Bay, CA February 6 - December 17 Moffett Federal Airfield, CA January 6 - December 23 Newark, CAJanuary 1 - December 27 Skyline Ridge Preserve, CA March 21 - December 15

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