Frost Dates for 97734 — Culver, Oregon

Half of springs at Madras 2 N, OR see their last 32°F night by May 19; only one in ten is past it by May 2, and one in ten still has one after June 7. Planting tender crops after May 28 leaves a 30% risk of a frost on them, after May 31 20%, and after June 7 10%. The 19 days between the even-odds date and the one-in-ten date is narrower than at 70% of the 103 Oregon stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 4 in half of years, as early as September 20 one year in ten, and holds off past October 18 one year in ten. A hard freeze of 28°F follows 13 days later, around October 17; in spring the one-in-ten date for 28°F is May 20, 18 days before the 32°F one. The freeze-free season lasts 136 days in a typical year, shorter than at 84% of the 103 Oregon stations; it reaches 159 days one year in ten and falls short of 110 one year in ten. On average 143 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 June 10, and return around September 19. Severe cold of 16°F or below comes every winter, usually between November 26 and February 22.

July is the warmest month at Madras 2 N, OR, averaging 87°F by day and 50°F at night; December is the coldest at 41°F and 23°F. A freezing night is all but certain in every month from October to May (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, June still brings one in 20% of years.

Warmth for growing adds up to 2,059 growing degree days a year (base 50°F), fewer than at 61% of the 103 Oregon stations. 26% of them (532) have built up by the end of June, and July adds the most, 567. Precipitation totals 11.3 inches a year, most in December (1.6") and least in August (0.3"); May to September bring 27% of it.

The nearest other station, Pelton Dam, OR, 16 miles north of Culver and 1,033 feet lower, has a last frost 14 days earlier (May 5), a first frost 3 days later (October 7), a season 18 days longer.

The first measurable snow (0.1 inch or more) in Culver usually arrives around December 4, and the last of the season around February 22. Those are the middle dates across the winters of 1991–2020 at Madras 2 N, OR, 11.8 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 86 days after the last snow.

ZIP 97734 is 12 miles from Madras 2 N, OR, which stands at 2,443 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 97741 (Madras). The 2023 USDA Plant Hardiness Zone Map lists ZIP 97734 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°C) over 1991–2020; a zone describes winter lows, not frost dates.