Frost Dates for 43515 — Delta, Ohio

Half of springs at Wauseon Wtp, OH see their last 32°F night by April 29; only one in ten is past it by April 14, and one in ten still has one after May 16. Planting tender crops after May 4 leaves a 30% risk of a frost on them, after May 9 20%, and after May 16 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 16 in half of years, as early as September 30 one year in ten, and holds off past October 31 one year in ten. A hard freeze of 28°F follows 13 days later, around October 29; in spring the one-in-ten date for 28°F is May 3, 13 days before the 32°F one. The freeze-free season lasts 170 days in a typical year, shorter than at 81% of the 148 Ohio stations; it reaches 190 days one year in ten and falls short of 146 one year in ten. On average 137 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 May 9, and return around October 5. Severe cold of 16°F or below comes every winter, usually between December 3 and March 16.

July is the warmest month at Wauseon Wtp, OH, averaging 84°F by day and 61°F at night; January is the coldest at 32°F and 17°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 41% of years.

Warmth for growing adds up to 2,856 growing degree days a year (base 50°F), fewer than at 88% of the 148 Ohio stations. 34% of them (966) have built up by the end of June, and July adds the most, 690. Precipitation totals 35.3 inches a year, most in May (3.9") and least in February (1.9"); May to September bring 51% of it.

The nearest other station, Toledo Express Airport, OH, 11 miles east of Delta, has a last frost 7 days earlier (April 22), a first frost 8 days later (October 24), a season 18 days longer.

The first measurable snow (0.1 inch or more) in Delta usually arrives around December 5, and the last of the season around March 22. Those are the middle dates across the winters of 1991–2020 at Wauseon Wtp, OH, 8.5 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 38 days after the last snow.

ZIP 43515 is 9 miles from Wauseon Wtp, OH, which stands at 750 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 43567 (Wauseon). The 2023 USDA Plant Hardiness Zone Map lists ZIP 43515 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°C) over 1991–2020; a zone describes winter lows, not frost dates.