Frost Dates for 53126 — Franksville, Wisconsin

Half of springs at Union Grove, WI see their last 32°F night by May 5; only one in ten is past it by April 21, and one in ten still has one after May 20. Planting tender crops after May 11 leaves a 30% risk of a frost on them, after May 15 20%, and after May 20 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 30% of the 182 Wisconsin stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 8 in half of years, as early as September 27 one year in ten, and holds off past October 23 one year in ten. A hard freeze of 28°F follows 12 days later, around October 20; in spring the one-in-ten date for 28°F is May 10, 10 days before the 32°F one. The freeze-free season lasts 156 days in a typical year, longer than at 50% of the 182 Wisconsin stations; it reaches 175 days one year in ten and falls short of 138 one year in ten. On average 145 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 12 days longer, to about May 17, and return around September 30. Severe cold of 16°F or below comes every winter, usually between November 22 and March 21.

July is the warmest month at Union Grove, WI, averaging 81°F by day and 61°F at night; January is the coldest at 28°F and 12°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 63% of years.

Warmth for growing adds up to 2,455 growing degree days a year (base 50°F), more than at 53% of the 182 Wisconsin stations. 31% of them (771) have built up by the end of June, and July adds the most, 643. Precipitation totals 35.2 inches a year, most in June (4.5") and least in February (1.5"); May to September bring 55% of it.

The nearest other station, Racine Batten Airport, WI, 8 miles east of Franksville, has a last frost 11 days earlier (April 24), a first frost 16 days later (October 24), a season 24 days longer.

The first measurable snow (0.1 inch or more) in Franksville usually arrives around November 30, and the last of the season around March 29. Those are the middle dates across the winters of 1991–2020 at Union Grove, WI, 7 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 37 days after the last snow.

ZIP 53126 is 7 miles from Union Grove, WI, which stands at 730 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 53182 (Union Grove). The 2023 USDA Plant Hardiness Zone Map lists ZIP 53126 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.