Frost Dates for 97031 — Hood River, Oregon

Half of springs at Hood Rvr Exp Stn, OR see their last 32°F night by April 20; only one in ten is past it by March 29, and one in ten still has one after May 9. Planting tender crops after April 28 leaves a 30% risk of a frost on them, after May 2 20%, and after May 9 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 13 in half of years, as early as September 30 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 15 days later, around October 28; in spring the one-in-ten date for 28°F is April 10, 29 days before the 32°F one. The freeze-free season lasts 177 days in a typical year, shorter than at 65% of the 103 Oregon stations; it reaches 206 days one year in ten and falls short of 152 one year in ten. On average 92 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 17 days longer, to about May 7, and return around October 1. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 71%.

July is the warmest month at Hood Rvr Exp Stn, OR, averaging 82°F by day and 56°F at night; December is the coldest at 40°F and 31°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 83% of years and May still brings one in 24% of years.

Warmth for growing adds up to 2,282 growing degree days a year (base 50°F), more than at 54% of the 103 Oregon stations. 30% of them (680) have built up by the end of June, and July adds the most, 577. Precipitation totals 30.2 inches a year, most in December (5.9") and least in July (0.2"); May to September bring 11% of it.

The nearest other station, Parkdale 1 NNE, OR, 10 miles south of Hood River and 1,020 feet higher, has a last frost 23 days later (May 13), a first frost 10 days earlier (October 3), a season 35 days shorter.

The first measurable snow (0.1 inch or more) in Hood River usually arrives around November 29, and the last of the season around February 14. Those are the middle dates across the winters of 1991–2020 at Hood Rvr Exp Stn, OR, 1.2 miles away: half of years saw snow earlier, half later. Snow fell in 84% of those winters. The last 32°F night of spring typically comes 65 days after the last snow.

ZIP 97031 is 1 mile from Hood Rvr Exp Stn, OR, which stands at 500 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 97031 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.