Frost dates in San Diego, California
NOAA 1991–2020 normals for a 32 °F freeze. Low spots and the edge of town run colder than downtown.
Short answer
Frost is too rare in San Diego to put a date on: at NOAA's San Diego Montgomery Fld station, 1 mile from the middle of San Diego, it hit 32 °F in fewer than 1 year in 10. San Diego is in USDA planting zone 10b.
Weather stations around San Diego
The first row is the date most people in San Diego go by. The others show how far the dates move across the area.
| Station | Last spring frost | First fall frost | Frost-free |
|---|---|---|---|
| San Diego Montgomery Fld 1 mi away, 417 ft | Frost too rare to date (32 °F in under 1 year in 10) | ||
| San Diego Miramar NAS 3 mi away, 477 ft | Frost too rare to date (32 °F in under 1 year in 10) | ||
| San Diego Lindbergh Fld 8 mi away, 15 ft | Frost too rare to date (32 °F in under 1 year in 10) | ||
| San Diego Seaworld 8 mi away, 14 ft | Frost too rare to date (32 °F in under 1 year in 10) | ||
| North Island NAS 10 mi away, 26 ft | Frost too rare to date (32 °F in under 1 year in 10) | ||
Distances are from the middle of San Diego as the Census Bureau maps it. The average date is NOAA's 50% date: half of years have a later last frost, or an earlier first one. Plan by the 1-in-10 date if a freeze would cost you plants. The planting zone is the USDA 2023 zone for ZIP code 92123, at the middle of the city.
Your exact ZIP code
San Diego covers a lot of ground. For the station nearest your own street, and its planting zone, type your ZIP code.
How these dates work
Frost dates come from NOAA's 1991 to 2020 Climate Normals, which work out from each weather station's daily lows how likely the last spring freeze and the first fall freeze (32 °F) are by each date. We use the station nearest the middle of your ZIP code and show its height and distance, since a station on a hill or by a lake can differ from your yard.
The average date is the 50% date: half of years have a freeze after the spring date or before the fall one. The 1-in-10 dates are NOAA's 10% dates, the ones to plan by if a late freeze would cost you plants. Within one yard, cold air pools in low spots while walls and paving hold heat, so some corners freeze before others.
More frost dates
All of California, station by station.
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Where the numbers come from
- USDA Plant Hardiness Zone Map, 2023. Agricultural Research Service, U.S. Department of Agriculture
- PRISM Climate Group, Oregon State University (zone data)
- NOAA NCEI, U.S. Climate Normals 1991–2020, annual/seasonal
- NOAA, Normals calculation methodology (frost-freeze probability dates)
- US Census Bureau, 2025 ZCTA gazetteer (ZIP code centers)
- US Census Bureau, 2025 city population estimates and place gazetteer