Frost Dates for 95338 — Mariposa, California

Half of springs at So Entrance Yosemite Np, CA see their last 32°F night by May 24; only one in ten is past it by May 3, and one in ten still has one after June 11. Planting tender crops after June 1 leaves a 30% risk of a frost on them, after June 5 20%, and after June 11 10%. The 18 days between the even-odds date and the one-in-ten date is narrower than at 93% of the 220 California stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 10 in half of years, as early as September 24 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 19 days later, around October 29; in spring the one-in-ten date for 28°F is May 29, 13 days before the 32°F one. The freeze-free season lasts 137 days in a typical year, shorter than at 94% of the 219 California stations; it reaches 163 days one year in ten and falls short of 112 one year in ten. On average 159 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 15 days longer, to about June 8, and return around September 26. Severe cold of 16°F or below comes in 93% of winters, usually between December 17 and February 13.

July is the warmest month at So Entrance Yosemite Np, CA, averaging 80°F by day and 51°F at night; December is the coldest at 44°F and 26°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 90% of years and June still brings one in 33% of years.

Warmth for growing adds up to 1,747 growing degree days a year (base 50°F), fewer than at 96% of the 283 California stations. 23% of them (398) have built up by the end of June, and July adds the most, 477. Precipitation totals 37.2 inches a year, most in January (7.6") and least in August (0.1"); May to September bring 9% of it.

The nearest other station, Yosemite Park Hq, CA, 25 miles northeast of Mariposa and 1,029 feet lower, has a last frost 33 days earlier (April 21), a first frost 17 days later (October 27), a season 49 days longer.

Measurable snow is rare here: only 0 of 19 winters from 1991 to 2020 recorded 0.1 inch or more at Exchequer Dam, CA, 19.5 miles away, so there is no typical first-snow date to plan around.

ZIP 95338 is 16 miles from So Entrance Yosemite Np, CA, which stands at 5,047 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 95338 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.