Frost Dates for 96022 — Cottonwood, California

Half of springs at Redding Municipal Airport, CA see their last 32°F night by March 3; only one in ten is past it by January 31, and one in ten still has one after April 9. Planting tender crops after March 17 leaves a 30% risk of a frost on them, after March 31 20%, and after April 9 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 November 21 in half of years, as early as November 7 one year in ten, and holds off past December 7 one year in ten. A hard freeze of 28°F follows 16 days later, around December 7; in spring the one-in-ten date for 28°F is March 1, 39 days before the 32°F one. The freeze-free season lasts 261 days in a typical year, shorter than at 63% of the 219 California stations; it reaches 299 days one year in ten and falls short of 223 one year in ten. On average 27 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 35 days longer, to about April 7, and return around November 9. Nights of 24°F, cold enough to damage hardier plants, come in 52% of winters and 16°F in 2%.

July is the warmest month at Redding Municipal Airport, CA, averaging 100°F by day and 67°F at night; December is the coldest at 56°F and 37°F. A freezing night is all but certain in December (a 90% chance or more). From May to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 77% of years and March still brings one in 45% of years and April still brings one in 20% of years.

Warmth for growing adds up to 5,311 growing degree days a year (base 50°F), more than at 74% of the 283 California stations. 37% of them (1,940) have built up by the end of June, and July adds the most, 1,037. Precipitation totals 33.5 inches a year, most in December (6.3") and least in July (0.1"); May to September bring 10% of it.

The nearest other station, Red Bluff Municipal Airport, CA, 15 miles south of Cottonwood, has a last frost 9 days earlier (February 22), a first frost 8 days later (November 29), a season 20 days longer.

Measurable snow is rare here: only 0 of 25 winters from 1991 to 2020 recorded 0.1 inch or more at Coleman Fisheries Stn, CA, 10.5 miles away, so there is no typical first-snow date to plan around.

ZIP 96022 is 11 miles from Redding Municipal Airport, CA, which stands at 497 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 96002 (Redding). The 2023 USDA Plant Hardiness Zone Map lists ZIP 96022 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.