Frost dates for Skyline Ridge Preserve, California
Half of years have their last spring frost by March 21 — but 1 year in 10 still frosts after April 28.
Every other site gives you one date. A frost date is not a date: it is a percentile from 30 years of records at a nearby weather station, and planting to the median means losing the crop in half of years. Both numbers are below, so you can choose the risk yourself.
The odds
Last spring frost
- Frost this late in 1 year in 10
- April 28
- 1 year in 5
- April 15
- 3 years in 10
- April 7
- 2 years in 5
- March 30
- Half of years (the median)
- March 21
First fall freeze
- Freeze this early in 1 year in 10
- November 21
- 1 year in 5
- November 29
- 3 years in 10
- December 5
- 2 years in 5
- December 10
- Half of years (the median)
- December 15
- Growing season
- about 275 days
- Hardiness zones nearby
- 10a, 9a, 9b
Where these numbers come from
NOAA NCEI 1991–2020 Climate Normals, station Skyline Ridge Preserve (USC00048273), at 37.31, -122.19. These are that station's own records, unshifted. The further your garden is from it, the less exactly they describe your ground — the planner resolves the nearest station to your own ZIP and lowers its confidence with distance, rather than presenting one number as if it were measured in your yard.
Cold air also pools in low ground on the clear, still nights when frost happens, so a hollow can freeze while a slope a hundred metres away does not. No table can know that about your garden. Your own logged frosts eventually can.
ZIP codes nearest this station
94002, 94019, 94020, 94021, 94022, 94024, 94025, 94027, 94028, 94040, 94041, 94043, 94060, 94061, 94062, 94063, 94070, 94074, 94085, 94086, 94087, 94089, 94301, 94303, 94304, 94305, 94306, 94560, 95002, 95005, 95006, 95007, 95008, 95010, 95014, 95017, 95018, 95030, 95032, 95033, 95041, 95050, 95051, 95053, 95054, 95060, 95062, 95064, 95065, 95066, 95070, 95073, 95117, 95124, 95126, 95128, 95129, 95130, 95134.
What can I plant here, and when? →
Nearby stations
The nearest stations, and how their last-frost dates compare — the frost gradient across your area, which no single station shows.
- Oakland Metro Intl Ap, CA — last frost by January 7
- Mt Hamilton, CA — last frost by May 3
- Livermore Hcn, CA — last frost by February 15
- San Francisco Oceanside, CA — last frost by December 30
- Lodi Hcn, CA — last frost by February 9
- Woodland 1 Wnw, CA — last frost by February 7
Other stations in California.
- Auburn, CA — last frost by February 25
- Fresno 5 Ne, CA — last frost by January 30
- Woodland Hills Pierce College, CA — last frost by January 24
- Burbank Glendale Pasadena Ap, CA — last frost by December 31
- Torrance Ap, CA — last frost by January 9
- Wrightwood, CA — last frost by May 16
- Lake Arrowhead, CA — last frost by May 5
- Tustin Irvine Rch Hcn, CA — last frost by January 5