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Frost Dates for Vandenberg AFB, CA

Last spring frost
Jan 20
First fall frost
Dec 19
Growing season
335 days
Hardiness zone
10a

In an average year around Vandenberg AFB, CA, the last spring frost (32°F) is about Jan 20 and the first fall frost is about Dec 19, giving roughly a 335-day growing season. To be safe most years, wait until Dec 16 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Vandenberg AFB, CA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Apr 5 Feb 28 Jan 26
Freeze (32°F) Feb 24 Jan 20 Dec 16
Hard (28°F) Jan 30 Jan 1 Dec 13
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Apr 5 Mar 27 Mar 16 Mar 7 Feb 28 Feb 23 Feb 16 Feb 7 Jan 26
32°F Feb 24 Feb 12 Feb 3 Jan 27 Jan 20 Jan 11 Jan 3 Dec 27 Dec 16
28°F Jan 30 Jan 18 Jan 10 Jan 5 Jan 1 Dec 29 Dec 25 Dec 20 Dec 13

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Vandenberg AFB, CA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Nov 3 Dec 1 Dec 22
Freeze (32°F) Nov 27 Dec 19 Jan 26
Hard (28°F) Dec 9 Dec 29 Jan 29
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Nov 3 Nov 16 Nov 21 Nov 27 Dec 1 Dec 4 Dec 8 Dec 13 Dec 22
32°F Nov 27 Dec 6 Dec 10 Dec 14 Dec 19 Dec 26 Jan 1 Jan 7 Jan 26
28°F Dec 9 Dec 18 Dec 21 Dec 25 Dec 29 Jan 1 Jan 5 Jan 12 Jan 29

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Lompoc, Ca, about 8.1 miles away@if(!empty($station['elevation_ft'])), at 75 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Vandenberg AFB, CA?

On average, the last spring frost (32°F) around Vandenberg AFB, CA is about Jan 20. In cooler years it can run later, so for a safer bet many gardeners wait until Dec 16.

When is the first frost in the fall?

The first fall frost around Vandenberg AFB, CA typically arrives about Dec 19. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Jan 20 on average, or Dec 16 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 335 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 93437 Planting calendar → California frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026