Frost Dates for 96094 — Weed, California

Half of springs at Mt Shasta, CA see their last 32°F night by May 6; only one in ten is past it by April 20, and one in ten still has one after May 28. Planting tender crops after May 15 leaves a 30% risk of a frost on them, after May 21 20%, and after May 28 10%. The 22 days between the even-odds date and the one-in-ten date is narrower than at 81% 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 12 in half of years, as early as September 27 one year in ten, and holds off past October 28 one year in ten. A hard freeze of 28°F follows 18 days later, around October 30; in spring the one-in-ten date for 28°F is May 4, 24 days before the 32°F one. The freeze-free season lasts 158 days in a typical year, shorter than at 90% of the 219 California stations; it reaches 180 days one year in ten and falls short of 132 one year in ten. On average 125 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 22 days longer, to about May 28, and return around September 25. Severe cold of 16°F or below comes in 91% of winters, usually between December 14 and January 24.

July is the warmest month at Mt Shasta, CA, averaging 85°F by day and 52°F at night; December is the coldest at 42°F and 28°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 66% of years.

Warmth for growing adds up to 2,169 growing degree days a year (base 50°F), fewer than at 92% of the 283 California stations. 28% of them (603) have built up by the end of June, and July adds the most, 572. Precipitation totals 37.6 inches a year, most in December (6.6") and least in August (0.2"); May to September bring 11% of it.

The nearest other station, Mt Shasta, CA, 10 miles south of Weed, has a last frost 9 days later (May 15), a first frost 6 days earlier (October 6), a season 15 days shorter.

The first measurable snow (0.1 inch or more) in Weed usually arrives around November 12, and the last of the season around April 19. Those are the middle dates across the winters of 1991–2020 at Mt Shasta, CA, 10.2 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 17 days after the last snow.

ZIP 96094 is 9 miles from Mt Shasta, CA, which stands at 3,535 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 96094 in zone 8a, the band where the coldest night of the year averaged 10 to 15°F (-12.2 to -9.4°C) over 1991–2020; a zone describes winter lows, not frost dates.