Frost Dates for 45833 — Delphos, Ohio

Half of springs at Van Wert 1 S, OH see their last 32°F night by April 21; only one in ten is past it by April 7, and one in ten still has one after May 6. Planting tender crops after April 26 leaves a 30% risk of a frost on them, after April 30 20%, and after May 6 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 77% of the 148 Ohio stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 26 in half of years, as early as October 13 one year in ten, and holds off past November 7 one year in ten. A hard freeze of 28°F follows 10 days later, around November 5; in spring the one-in-ten date for 28°F is April 24, 12 days before the 32°F one. The freeze-free season lasts 187 days in a typical year, longer than at 75% of the 148 Ohio stations; it reaches 206 days one year in ten and falls short of 167 one year in ten. On average 125 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 9 days longer, to about April 30, and return around October 14. Severe cold of 16°F or below comes every winter, usually between December 5 and March 11.

July is the warmest month at Van Wert 1 S, OH, averaging 85°F by day and 64°F at night; January is the coldest at 33°F and 18°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 20% of years.

Warmth for growing adds up to 3,291 growing degree days a year (base 50°F), more than at 59% of the 148 Ohio stations. 35% of them (1,147) have built up by the end of June, and July adds the most, 758. Precipitation totals 40.6 inches a year, most in May (4.8") and least in February (2.1"); May to September bring 52% of it.

The nearest other station, Lima Wwtp, OH, 14 miles southeast of Delphos, has a last frost 3 days later (April 24), a first frost 2 days earlier (October 24), a season 5 days shorter.

The first measurable snow (0.1 inch or more) in Delphos usually arrives around December 10, and the last of the season around March 2. Those are the middle dates across the winters of 1991–2020 at Grover Hill, OH, 14.2 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 50 days after the last snow.

ZIP 45833 is 13 miles from Van Wert 1 S, OH, which stands at 790 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 45891 (Van Wert). The 2023 USDA Plant Hardiness Zone Map lists ZIP 45833 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.