Frost Dates for 69357 — Mitchell, Nebraska

Half of springs at Mitchell 5E, NE see their last 32°F night by May 7; only one in ten is past it by April 26, and one in ten still has one after May 21. Planting tender crops after May 13 leaves a 30% risk of a frost on them, after May 17 20%, and after May 21 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 72% of the 68 Nebraska stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 2 in half of years, as early as September 18 one year in ten, and holds off past October 15 one year in ten. A hard freeze of 28°F follows 8 days later, around October 10; in spring the one-in-ten date for 28°F is May 11, 10 days before the 32°F one. The freeze-free season lasts 147 days in a typical year, shorter than at 91% of the 68 Nebraska stations; it reaches 166 days one year in ten and falls short of 127 one year in ten. On average 170 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 11 days longer, to about May 18, and return around September 24. Severe cold of 16°F or below comes every winter, usually between November 7 and March 24.

July is the warmest month at Mitchell 5E, NE, averaging 88°F by day and 59°F at night; December is the coldest at 40°F and 16°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 77% of years.

Warmth for growing adds up to 2,710 growing degree days a year (base 50°F), fewer than at 94% of the 68 Nebraska stations. 32% of them (870) have built up by the end of June, and July adds the most, 728.

The nearest other station, Scottsbluff 1E, NE, 9 miles southeast of Mitchell and 171 feet lower, has a last frost 1 day later (May 8), a first frost 1 day later (October 3).

The first measurable snow (0.1 inch or more) in Mitchell usually arrives around November 1, and the last of the season around May 2. Those are the middle dates across the winters of 1991–2020 at Scottsbluff 1E, NE, 9.3 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 5 days after the last snow.

ZIP 69357 is 5 miles from Mitchell 5E, NE, which stands at 4,080 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 69357 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.