Frost Dates for 95948 — Gridley, California

Half of springs at Oroville Municipal Airport, CA see their last 32°F night by January 29; only one in ten is past it by December 28, and one in ten still has one after February 28. Planting tender crops after February 12 leaves a 30% risk of a frost on them, after February 20 20%, and after February 28 10%. The 30 days between the even-odds date and the one-in-ten date is narrower than at 48% 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 7 in half of years, as early as November 20 one year in ten, and holds off past January 6 one year in ten. A hard freeze of 28°F follows 20 days later, around December 27; in spring the one-in-ten date for 28°F is February 6, 22 days before the 32°F one. The freeze-free season lasts 317 days in a typical year, longer than at 73% of the 219 California stations; it reaches 349 days one year in ten and falls short of 279 one year in ten. On average 11 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 36 days longer, to about March 6, and return around November 24. A 24°F night is unusual: 12% of winters had one.

July is the warmest month at Oroville Municipal Airport, CA, averaging 96°F by day and 65°F at night; December is the coldest at 55°F and 40°F. From March to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 38% of years.

Warmth for growing adds up to 5,120 growing degree days a year (base 50°F), more than at 67% of the 283 California stations. 38% of them (1,923) have built up by the end of June, and July adds the most, 945. Precipitation totals 25.6 inches a year, most in January (5.2") and least in July (0.0"); May to September bring 6% of it.

The nearest other station, Oroville, CA, 14 miles northeast of Gridley, has a last frost 1 day later (January 30), a first frost 6 days later (December 13), a season 4 days longer.

Measurable snow is rare here: only 0 of 27 winters from 1991 to 2020 recorded 0.1 inch or more at Oroville, CA, 14.2 miles away, so there is no typical first-snow date to plan around.

ZIP 95948 is 11 miles from Oroville Municipal Airport, CA, which stands at 190 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 95948 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.