Frost Dates for 92397 — Wrightwood, California

Half of springs at Wrightwood, CA see their last 32°F night by May 16; only one in ten is past it by April 25, and one in ten still has one after June 9. Planting tender crops after May 29 leaves a 30% risk of a frost on them, after June 3 20%, and after June 9 10%. The 24 days between the even-odds date and the one-in-ten date is narrower than at 74% of the 220 California stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.

In fall the first 32°F night comes by October 13 in half of years, as early as September 25 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 17 days later, around October 30; in spring the one-in-ten date for 28°F is May 13, 27 days before the 32°F one. The freeze-free season lasts 151 days in a typical year, shorter than at 91% of the 219 California stations; it reaches 178 days one year in ten and falls short of 122 one year in ten. On average 159 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 19 days longer, to about June 4, and return around October 1. Severe cold of 16°F or below comes in 95% of winters, usually between December 17 and February 14.

July is the warmest month at Wrightwood, CA, averaging 83°F by day and 53°F at night; December is the coldest at 48°F and 25°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 71% of years and June still brings one in 25% of years.

Warmth for growing adds up to 2,050 growing degree days a year (base 50°F), fewer than at 93% of the 283 California stations. 27% of them (553) have built up by the end of June, and July adds the most, 555. Precipitation totals 21.1 inches a year, most in February (4.9") and least in June (0.1"); May to September bring 13% of it.

The nearest other station, El Mirage, CA, 16 miles north of Wrightwood and 3,050 feet lower, has a last frost 56 days earlier (March 21), a first frost 30 days later (November 12), a season 84 days longer.

Measurable snow is rare here: only 0 of 15 winters from 1991 to 2020 recorded 0.1 inch or more at Crystal Lake Fc238c, CA, 12.6 miles away, so there is no typical first-snow date to plan around.

ZIP 92397 is under a mile from Wrightwood, CA, which stands at 6,000 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 92371 (Phelan). The 2023 USDA Plant Hardiness Zone Map lists ZIP 92397 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.