Frost Dates for 97348 — Halsey, Oregon

Half of springs at Corvallis 10 SSW, OR see their last 32°F night by April 11; only one in ten is past it by March 11, and one in ten still has one after May 5. Planting tender crops after April 24 leaves a 30% risk of a frost on them, after April 29 20%, and after May 5 10%. The 24 days between the even-odds date and the one-in-ten date is wider than at 60% of the 103 Oregon 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 30 in half of years, as early as October 8 one year in ten, and holds off past November 25 one year in ten. A hard freeze of 28°F follows 21 days later, around November 20; in spring the one-in-ten date for 28°F is March 30, 36 days before the 32°F one. The freeze-free season lasts 203 days in a typical year, longer than at 54% of the 103 Oregon stations; it reaches 241 days one year in ten and falls short of 172 one year in ten. On average 60 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 30 days longer, to about May 11, and return around October 11. Nights of 24°F, cold enough to damage hardier plants, come in 90% of winters and 16°F in 22%.

August is the warmest month at Corvallis 10 SSW, OR, averaging 82°F by day and 51°F at night; December is the coldest at 46°F and 34°F. A freezing night is all but certain in every month from November to February (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 87% of years and April still brings one in 63% of years and May still brings one in 17% of years.

Warmth for growing adds up to 2,088 growing degree days a year (base 50°F), fewer than at 58% of the 103 Oregon stations. 27% of them (561) have built up by the end of June, and August adds the most, 508. Precipitation totals 41.5 inches a year, most in December (8.0") and least in July (0.3"); May to September bring 12% of it.

The nearest other station, Lebanon, OR, 15 miles northeast of Halsey, has a last frost 28 days earlier (March 14), a first frost 19 days later (November 18), a season 45 days longer.

Measurable snow is rare here: only 0 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Waterloo, OR, 15.4 miles away, so there is no typical first-snow date to plan around.

ZIP 97348 is 10 miles from Corvallis 10 SSW, OR, which stands at 312 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 97333 (Corvallis). The 2023 USDA Plant Hardiness Zone Map lists ZIP 97348 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.