Frost Dates for 43015 — Delaware, Ohio

Half of springs at Marysville, OH see their last 32°F night by April 19; only one in ten is past it by April 5, and one in ten still has one after May 5. Planting tender crops after April 25 leaves a 30% risk of a frost on them, after April 29 20%, and after May 5 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 53% 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 11 days later, around November 6; in spring the one-in-ten date for 28°F is April 22, 13 days before the 32°F one. The freeze-free season lasts 188 days in a typical year, longer than at 76% of the 148 Ohio stations; it reaches 208 days one year in ten and falls short of 168 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 11 days longer, to about April 30, and return around October 14. Severe cold of 16°F or below comes every winter, usually between December 10 and March 6.

July is the warmest month at Marysville, OH, averaging 85°F by day and 64°F at night; January is the coldest at 35°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 16% of years.

Warmth for growing adds up to 3,424 growing degree days a year (base 50°F), more than at 72% of the 148 Ohio stations. 36% of them (1,234) have built up by the end of June, and July adds the most, 764. Precipitation totals 40.6 inches a year, most in June (4.9") and least in February (2.3"); May to September bring 50% of it.

The nearest other station, Westerville, OH, 13 miles southeast of Delaware and 168 feet lower, has a last frost 3 days later (April 22), a first frost 2 days earlier (October 24), a season 5 days shorter.

The first measurable snow (0.1 inch or more) in Delaware usually arrives around December 5, and the last of the season around March 14. Those are the middle dates across the winters of 1991–2020 at Marysville, OH, 12.6 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 36 days after the last snow.

ZIP 43015 is 13 miles from Marysville, OH, which stands at 970 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 43015 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.