Frost Dates for 44824 — Castalia, Ohio

Half of springs at Sandusky, OH see their last 32°F night by April 10; only one in ten is past it by March 31, and one in ten still has one after April 23. Planting tender crops after April 16 leaves a 30% risk of a frost on them, after April 19 20%, and after April 23 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 97% of the 148 Ohio stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 5 in half of years, as early as October 23 one year in ten, and holds off past November 20 one year in ten. A hard freeze of 28°F follows 11 days later, around November 16; in spring the one-in-ten date for 28°F is April 14, 9 days before the 32°F one. The freeze-free season lasts 209 days in a typical year, longer than at 99% of the 148 Ohio stations; it reaches 227 days one year in ten and falls short of 190 one year in ten. On average 104 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 21, and return around October 26. Severe cold of 16°F or below comes every winter, usually between December 18 and March 2.

July is the warmest month at Sandusky, OH, averaging 82°F by day and 67°F at night; January is the coldest at 34°F and 22°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 87% of years.

Warmth for growing adds up to 3,338 growing degree days a year (base 50°F), more than at 62% of the 148 Ohio stations. 33% of them (1,098) have built up by the end of June, and July adds the most, 767. Precipitation totals 34.2 inches a year, most in April (3.8") and least in February (1.8"); May to September bring 49% of it.

The nearest other station, Norwalk Wwtp, OH, 13 miles southeast of Castalia, has a last frost 15 days later (April 25), a first frost 11 days earlier (October 25), a season 26 days shorter.

The first measurable snow (0.1 inch or more) in Castalia usually arrives around November 25, and the last of the season around March 27. Those are the middle dates across the winters of 1991–2020 at Norwalk Wwtp, OH, 13.1 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 14 days after the last snow.

ZIP 44824 is 6 miles from Sandusky, OH, which stands at 584 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 44870 (Sandusky). The 2023 USDA Plant Hardiness Zone Map lists ZIP 44824 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.