Frost Dates for 45230 — Cincinnati, Ohio

Half of springs at Cincinnati Lunken Airport, OH see their last 32°F night by April 16; only one in ten is past it by April 2, and one in ten still has one after May 3. Planting tender crops after April 23 leaves a 30% risk of a frost on them, after April 27 20%, and after May 3 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 25 in half of years, as early as October 12 one year in ten, and holds off past November 5 one year in ten. A hard freeze of 28°F follows 10 days later, around November 4; in spring the one-in-ten date for 28°F is April 18, 15 days before the 32°F one. The freeze-free season lasts 190 days in a typical year, longer than at 82% of the 148 Ohio stations; it reaches 210 days one year in ten and falls short of 168 one year in ten. On average 102 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 13 days longer, to about April 29, and return around October 14. Severe cold of 16°F or below comes every winter, usually between December 10 and February 28.

July is the warmest month at Cincinnati Lunken Airport, OH, averaging 87°F by day and 65°F at night; January is the coldest at 41°F and 24°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 14% of years.

Warmth for growing adds up to 3,763 growing degree days a year (base 50°F), more than at 94% of the 148 Ohio stations. 36% of them (1,371) have built up by the end of June, and July adds the most, 804. Precipitation totals 43.5 inches a year, most in May (4.7") and least in February (2.8"); May to September bring 46% of it.

The nearest other station, Milford, OH, 9 miles northeast of Cincinnati, has a last frost 7 days later (April 23), a first frost 7 days earlier (October 18), a season 13 days shorter.

The first measurable snow (0.1 inch or more) in Cincinnati usually arrives around December 7, and the last of the season around March 16. Those are the middle dates across the winters of 1991–2020 at Cheviot, OH, 13.6 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 31 days after the last snow.

ZIP 45230 is 2 miles from Cincinnati Lunken Airport, OH, which stands at 490 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 28 other ZIP codes share the station; its figures are presented in full for 45215 (Cincinnati). The 2023 USDA Plant Hardiness Zone Map lists ZIP 45230 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.