Frost Dates for 68763 — Oneill, Nebraska

Half of springs at O'Neill, NE see their last 32°F night by May 3; only one in ten is past it by April 18, and one in ten still has one after May 16. Planting tender crops after May 7 leaves a 30% risk of a frost on them, after May 11 20%, and after May 16 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 29% of the 68 Nebraska stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 5 in half of years, as early as September 22 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 10 days later, around October 15; in spring the one-in-ten date for 28°F is May 8, 8 days before the 32°F one. The freeze-free season lasts 155 days in a typical year, shorter than at 82% of the 68 Nebraska stations; it reaches 176 days one year in ten and falls short of 139 one year in ten. On average 165 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 9 days longer, to about May 12, and return around September 28. Severe cold of 16°F or below comes every winter, usually between November 10 and March 24.

July is the warmest month at O'Neill, NE, averaging 87°F by day and 62°F at night; January is the coldest at 32°F and 11°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 60% of years.

Warmth for growing adds up to 2,912 growing degree days a year (base 50°F), fewer than at 85% of the 68 Nebraska stations. 32% of them (935) have built up by the end of June, and July adds the most, 761. Precipitation totals 26.0 inches a year, most in May (4.2") and least in January (0.5"); May to September bring 63% of it.

The nearest other station, Atkinson 3SW, NE, 22 miles west of Oneill, has a last frost 1 day later (May 4), a first frost 1 day earlier (October 4), a season 3 days shorter.

The first measurable snow (0.1 inch or more) in Oneill usually arrives around November 14, and the last of the season around March 28. Those are the middle dates across the winters of 1991–2020 at O'Neill, NE, 4.8 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 36 days after the last snow.

ZIP 68763 is 5 miles from O'Neill, NE, which stands at 1,990 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 68763 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.