Frost Dates for 45628 — Frankfort, Ohio

Half of springs at Chillicothe Mound City, OH see their last 32°F night by April 20; only one in ten is past it by April 6, and one in ten still has one after May 7. Planting tender crops after April 26 leaves a 30% risk of a frost on them, after May 1 20%, and after May 7 10%. The 17 days between the even-odds date and the one-in-ten date is narrower than at 24% of the 148 Ohio stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 22 in half of years, as early as October 7 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 11 days later, around November 2; in spring the one-in-ten date for 28°F is April 22, 15 days before the 32°F one. The freeze-free season lasts 184 days in a typical year, longer than at 65% of the 148 Ohio stations; it reaches 204 days one year in ten and falls short of 163 one year in ten. On average 114 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 10 days longer, to about April 30, and return around October 10. Severe cold of 16°F or below comes every winter, usually between December 5 and March 11.

July is the warmest month at Chillicothe Mound City, OH, averaging 85°F by day and 64°F at night; January is the coldest at 39°F and 21°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 21% of years.

Warmth for growing adds up to 3,538 growing degree days a year (base 50°F), more than at 80% of the 148 Ohio stations. 37% of them (1,295) have built up by the end of June, and July adds the most, 761.

The nearest other station, Washington Court House, OH, 16 miles northwest of Frankfort and 307 feet higher, has a last frost 3 days later (April 23), a first frost 1 day earlier (October 21), a season 3 days shorter.

The first measurable snow (0.1 inch or more) in Frankfort usually arrives around December 20, and the last of the season around March 9. Those are the middle dates across the winters of 1991–2020 at Chillicothe Mound City, OH, 10.2 miles away: half of years saw snow earlier, half later. Snow fell in 83% of those winters. The last 32°F night of spring typically comes 42 days after the last snow.

ZIP 45628 is 10 miles from Chillicothe Mound City, OH, which stands at 650 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 45601 (Chillicothe). The 2023 USDA Plant Hardiness Zone Map lists ZIP 45628 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.