Frost Dates for 91906 — Campo, California

Half of springs at Campo, CA see their last 32°F night by April 30; only one in ten is past it by April 9, and one in ten still has one after June 1. Planting tender crops after May 13 leaves a 30% risk of a frost on them, after May 19 20%, and after June 1 10%. The 32 days between the even-odds date and the one-in-ten date is wider than at 55% 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 September 30 one year in ten, and holds off past November 12 one year in ten. A hard freeze of 28°F follows 19 days later, around November 14; in spring the one-in-ten date for 28°F is April 28, 34 days before the 32°F one. The freeze-free season lasts 174 days in a typical year, shorter than at 88% of the 219 California stations; it reaches 207 days one year in ten and falls short of 135 one year in ten. On average 71 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 June 3, and return around October 2. Nights of 24°F, cold enough to damage hardier plants, come in 97% of winters and 16°F in 6%.

August is the warmest month at Campo, CA, averaging 95°F by day and 54°F at night; December is the coldest at 63°F and 33°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From July to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 43% of years and June still brings one in 11% of years.

Warmth for growing adds up to 3,872 growing degree days a year (base 50°F), fewer than at 65% of the 283 California stations. 32% of them (1,223) have built up by the end of June, and August adds the most, 764. Precipitation totals 15.6 inches a year, most in February (3.5") and least in June (0.1"); May to September bring 10% of it.

The nearest other station, Mt Laguna #3, CA, 14 miles north of Campo and 3,290 feet higher, has a last frost 8 days earlier (April 22), a first frost 13 days later (November 8), a season 23 days longer.

Measurable snow is rare here: only 4 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Campo, CA, 2.6 miles away, so there is no typical first-snow date to plan around.

ZIP 91906 is 3 miles from Campo, CA, which stands at 2,630 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 91906 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°C) over 1991–2020; a zone describes winter lows, not frost dates.