Frost Dates for 92256 — Morongo Valley, California

Half of springs at Morongo Valley N, CA see their last 32°F night by February 25; only one in ten is past it by January 7, and one in ten still has one after April 3. Planting tender crops after March 11 leaves a 30% risk of a frost on them, after March 22 20%, and after April 3 10%. The 37 days between the even-odds date and the one-in-ten date is wider than at 79% 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 December 15 in half of years, as early as November 23 one year in ten, and holds off past January 16 one year in ten. A hard freeze of 28°F follows 22 days later, around January 6; in spring the one-in-ten date for 28°F is February 28, 34 days before the 32°F one. The freeze-free season lasts 297 days in a typical year, longer than at 63% of the 219 California stations; it reaches 343 days one year in ten and falls short of 250 one year in ten. On average 13 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 34 days longer, to about March 31, and return around December 1. A 24°F night is unusual: 14% of winters had one.

August is the warmest month at Morongo Valley N, CA, averaging 94°F by day and 70°F at night; December is the coldest at 59°F and 40°F. From May to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 52% of years and March still brings one in 35% of years and April still brings one in 12% of years.

Warmth for growing adds up to 5,671 growing degree days a year (base 50°F), more than at 83% of the 283 California stations. 36% of them (2,037) have built up by the end of June, and August adds the most, 998. Precipitation totals 9.4 inches a year, most in February (2.9") and least in June (0.0"); May to September bring 7% of it.

The nearest other station, Yucca Valley, CA, 11 miles northeast of Morongo Valley, has a last frost 17 days later (March 14), a first frost 17 days earlier (November 28), a season 42 days shorter.

Measurable snow is rare here: only 0 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Palm Springs, CA, 16.8 miles away, so there is no typical first-snow date to plan around.

ZIP 92256 is 1 mile from Morongo Valley N, CA, which stands at 3,145 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 92256 in zone 9b, the band where the coldest night of the year averaged 25 to 30°F (-3.9 to -1.1°C) over 1991–2020; a zone describes winter lows, not frost dates.