Frost Dates for 65770 — Walnut Grove, Missouri

Half of springs at Ash Grove 4S, MO see their last 32°F night by April 11; only one in ten is past it by March 25, and one in ten still has one after April 29. Planting tender crops after April 18 leaves a 30% risk of a frost on them, after April 22 20%, and after April 29 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 82% of the 158 Missouri 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 13 one year in ten, and holds off past November 5 one year in ten. A hard freeze of 28°F follows 9 days later, around November 2; in spring the one-in-ten date for 28°F is April 15, 14 days before the 32°F one. The freeze-free season lasts 196 days in a typical year, longer than at 54% of the 158 Missouri stations; it reaches 217 days one year in ten and falls short of 176 one year in ten. On average 104 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 April 22, and return around October 16. Severe cold of 16°F or below comes every winter, usually between December 9 and February 27.

July is the warmest month at Ash Grove 4S, MO, averaging 91°F by day and 68°F at night; January is the coldest at 44°F and 24°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 77% of years.

Warmth for growing adds up to 4,402 growing degree days a year (base 50°F), more than at 85% of the 158 Missouri stations. 37% of them (1,637) have built up by the end of June, and July adds the most, 907. Precipitation totals 43.6 inches a year, most in May (5.6") and least in January (2.1"); May to September bring 51% of it.

The nearest other station, Springfield, MO, 14 miles southeast of Walnut Grove, has a last frost 2 days earlier (April 9), a first frost 3 days later (October 27), a season 3 days longer.

The first measurable snow (0.1 inch or more) in Walnut Grove usually arrives around December 25, and the last of the season around March 3. Those are the middle dates across the winters of 1991–2020 at Ash Grove 4S, MO, 10.7 miles away: half of years saw snow earlier, half later. Snow fell in 88% of those winters. The last 32°F night of spring typically comes 39 days after the last snow.

ZIP 65770 is 11 miles from Ash Grove 4S, MO, which stands at 1,129 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 65604 (Ash Grove). The 2023 USDA Plant Hardiness Zone Map lists ZIP 65770 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.