Frost Dates for 53705 — Madison, Wisconsin

Half of springs at Charmany Farm, WI see their last 32°F night by April 28; only one in ten is past it by April 14, and one in ten still has one after May 11. Planting tender crops after May 3 leaves a 30% risk of a frost on them, after May 6 20%, and after May 11 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 84% of the 182 Wisconsin stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 15 in half of years, as early as September 29 one year in ten, and holds off past October 29 one year in ten. A hard freeze of 28°F follows 10 days later, around October 25; in spring the one-in-ten date for 28°F is May 1, 10 days before the 32°F one. The freeze-free season lasts 169 days in a typical year, longer than at 83% of the 182 Wisconsin stations; it reaches 190 days one year in ten and falls short of 149 one year in ten. On average 146 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 May 7, and return around October 4. Severe cold of 16°F or below comes every winter, usually between November 21 and March 21.

July is the warmest month at Charmany Farm, WI, averaging 82°F by day and 62°F at night; January is the coldest at 27°F and 10°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 38% of years.

Warmth for growing adds up to 2,645 growing degree days a year (base 50°F), more than at 76% of the 182 Wisconsin stations. 33% of them (871) have built up by the end of June, and July adds the most, 673. Precipitation totals 39.3 inches a year, most in June (5.5") and least in January (1.5"); May to September bring 57% of it.

The nearest other station, Uw Arboretum - Madison, WI, 2 miles southeast of Madison and 176 feet lower, has a last frost 3 days later (May 1), a first frost 6 days earlier (October 9), a season 8 days shorter.

The first measurable snow (0.1 inch or more) in Madison usually arrives around November 23, and the last of the season around March 30. Those are the middle dates across the winters of 1991–2020 at Charmany Farm, WI, 1.8 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 29 days after the last snow.

ZIP 53705 is 2 miles from Charmany Farm, WI, which stands at 1,046 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 53719 (Madison). The 2023 USDA Plant Hardiness Zone Map lists ZIP 53705 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.