Frost Dates for 93561 — Tehachapi, California

Half of springs at Tehachapi 4 SE, CA see their last 32°F night by April 28; only one in ten is past it by April 11, and one in ten still has one after May 21. Planting tender crops after May 5 leaves a 30% risk of a frost on them, after May 11 20%, and after May 21 10%. The 23 days between the even-odds date and the one-in-ten date is narrower than at 78% 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 26 in half of years, as early as October 4 one year in ten, and holds off past November 17 one year in ten. A hard freeze of 28°F follows 21 days later, around November 16; in spring the one-in-ten date for 28°F is April 30, 21 days before the 32°F one. The freeze-free season lasts 183 days in a typical year, shorter than at 86% of the 219 California stations; it reaches 209 days one year in ten and falls short of 154 one year in ten. On average 82 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 18 days longer, to about May 16, and return around October 10. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 54%.

July is the warmest month at Tehachapi 4 SE, CA, averaging 86°F by day and 58°F at night; December is the coldest at 51°F and 31°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 39% of years.

Warmth for growing adds up to 2,922 growing degree days a year (base 50°F), fewer than at 85% of the 283 California stations. 28% of them (817) have built up by the end of June, and July adds the most, 680.

The nearest other station, Mojave, CA, 20 miles east of Tehachapi and 1,485 feet lower, has a last frost 44 days earlier (March 15), a first frost 22 days later (November 17), a season 58 days longer.

Measurable snow is rare here: only 0 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Tejon Rancho, CA, 15.6 miles away, so there is no typical first-snow date to plan around.

ZIP 93561 is 5 miles from Tehachapi 4 SE, CA, which stands at 4,220 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 93561 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.