When is the last frost in Concord, CA?

For ZIP code 94519, the average last spring frost (32°F) is January 9, based on NOAA 1991-2020 climate normals for the Concord Buchanan Fld, CA weather station. There is a 1-in-10 chance of a frost after February 12.

When is the first frost in Concord, CA?

The average first fall frost (32°F) is December 14. There is a 1-in-10 chance of frost by November 28, so tender plants are at risk from that point on.

How long is the growing season in 94519?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 343 days long.

Are these frost dates a forecast?

No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.

Frost dates for 94519Concord, CA

The average last spring frost in Concord is January 9 and the average first fall frost is December 14, giving a typical growing season of about 343 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Jan 9
Average first fall frost: Dec 14
Growing season: 343 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
Temperature	Last spring: 90% / 50% / 10% chance	First fall: 10% / 50% / 90% chance	Growing season (50%)	Years with at least one
Light frost (36°F)	Jan 12 · Feb 14 · Mar 13	Nov 14 · Dec 1 · Dec 26	294 days	99%
Frost / freeze (32°F)	Dec 16 · Jan 9 · Feb 12	Nov 28 · Dec 14 · Jan 16	343 days	79%
Hard freeze (28°F)	Dec 10 · Dec 30 · Jan 19	Dec 5 · Dec 23 · Jan 12	365 days	27%

Where these dates come from

ZIP code 94519 is matched to the NOAA station Concord Buchanan Fld, CA, 3.9 km away, at 18 ft elevation (94 ft lower than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Concord Buchanan Fld, CA (used)	18 ft	Jan 9	Dec 14
Concord Wwtp, CA	40 ft	Jan 7	Dec 19
Martinez Wtp, CA	40 ft	Feb 28	Nov 22
Mt Diablo Junction, CA	2,170 ft	Mar 8	Dec 22

Frost dates near Concord

Concord, CA 94522 · last Jan 7, first Dec 19
Pleasant Hill, CA 94523 · last Jan 7, first Dec 19
Walnut Creek, CA 94598 · last Jan 7, first Dec 19
Pittsburg, CA 94565 · last Jan 9, first Dec 14
Martinez, CA 94553 · last Feb 28, first Nov 22
Clayton, CA 94517 · last Feb 15, first Dec 2
Lafayette, CA 94549 · last Jan 3, first Jan 1
Alamo, CA 94507 · last Jan 3, first Jan 1

Frequently asked questions

When is the last frost in Concord, CA?: For ZIP code 94519, the average last spring frost (32°F) is January 9, based on NOAA 1991-2020 climate normals for the Concord Buchanan Fld, CA weather station. There is a 1-in-10 chance of a frost after February 12.
When is the first frost in Concord, CA?: The average first fall frost (32°F) is December 14. There is a 1-in-10 chance of frost by November 28, so tender plants are at risk from that point on.
How long is the growing season in 94519?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 343 days long.
Are these frost dates a forecast?: No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.