Frost Dates for 97463 — Oakridge, Oregon

Half of springs at Oakridge Fish Hatchery, OR see their last 32°F night by April 24; only one in ten is past it by March 31, and one in ten still has one after May 11. Planting tender crops after May 1 leaves a 30% risk of a frost on them, after May 5 20%, and after May 11 10%. The 17 days between the even-odds date and the one-in-ten date is narrower than at 83% of the 103 Oregon stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 24 in half of years, as early as October 2 one year in ten, and holds off past November 13 one year in ten. A hard freeze of 28°F follows 20 days later, around November 13; in spring the one-in-ten date for 28°F is April 18, 23 days before the 32°F one. The freeze-free season lasts 183 days in a typical year, shorter than at 61% of the 103 Oregon stations; it reaches 212 days one year in ten and falls short of 154 one year in ten. On average 79 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 18 days longer, to about May 12, and return around October 2. Nights of 24°F, cold enough to damage hardier plants, come in 94% of winters and 16°F in 17%.

August is the warmest month at Oakridge Fish Hatchery, OR, averaging 81°F by day and 50°F at night; December is the coldest at 42°F and 32°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 84% of years and May still brings one in 34% of years.

Warmth for growing adds up to 1,883 growing degree days a year (base 50°F), fewer than at 65% of the 103 Oregon stations. 27% of them (501) have built up by the end of June, and August adds the most, 480. Precipitation totals 45.8 inches a year, most in December (7.5") and least in July (0.5"); May to September bring 17% of it.

The nearest other station, Lookout Pt Dam, OR, 19 miles northwest of Oakridge and 563 feet lower, has a last frost 48 days earlier (March 7), a first frost 34 days later (November 27), a season 80 days longer.

The first measurable snow (0.1 inch or more) in Oakridge usually arrives around December 23, and the last of the season around February 23. Those are the middle dates across the winters of 1991–2020 at Oakridge Fish Hatchery, OR, 0.4 miles away: half of years saw snow earlier, half later. Snow fell in 81% of those winters. The last 32°F night of spring typically comes 60 days after the last snow.

ZIP 97463 is under a mile from Oakridge Fish Hatchery, OR, which stands at 1,275 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 97463 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.