Frost Dates for 53402 — Racine, Wisconsin

Half of springs at Racine Batten Airport, WI see their last 32°F night by April 24; only one in ten is past it by April 11, and one in ten still has one after May 10. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 4 20%, and after May 10 10%. The 16 days between the even-odds date and the one-in-ten date is wider than at 70% of the 182 Wisconsin stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 24 in half of years, as early as October 10 one year in ten, and holds off past November 5 one year in ten. A hard freeze of 28°F follows 11 days later, around November 4; in spring the one-in-ten date for 28°F is April 25, 15 days before the 32°F one. The freeze-free season lasts 180 days in a typical year, longer than at 96% of the 182 Wisconsin stations; it reaches 200 days one year in ten and falls short of 161 one year in ten. On average 126 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 May 7, and return around October 13. Severe cold of 16°F or below comes every winter, usually between December 1 and March 12.

July is the warmest month at Racine Batten Airport, WI, averaging 81°F by day and 63°F at night; January is the coldest at 31°F and 16°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 29% of years.

Warmth for growing adds up to 2,703 growing degree days a year (base 50°F), more than at 83% of the 182 Wisconsin stations. 29% of them (775) have built up by the end of June, and July adds the most, 690. Precipitation totals 31.9 inches a year, most in June (4.0") and least in February (1.1"); May to September bring 53% of it.

The nearest other station, Racine, WI, 5 miles south of Racine, has a last frost 4 days earlier (April 20), the same first-frost date, a season 4 days longer.

The first measurable snow (0.1 inch or more) in Racine usually arrives around November 27, and the last of the season around March 31. Those are the middle dates across the winters of 1991–2020 at Racine, WI, 4.5 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 24 days after the last snow.

ZIP 53402 is under a mile from Racine Batten Airport, WI, which stands at 674 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 53402 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.