Frost Dates for 53913 — Baraboo, Wisconsin

Half of springs at Baraboo, 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 21. Planting tender crops after May 12 leaves a 30% risk of a frost on them, after May 16 20%, and after May 21 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 5 in half of years, as early as September 22 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 12 days later, around October 17; in spring the one-in-ten date for 28°F is May 9, 12 days before the 32°F one. The freeze-free season lasts 152 days in a typical year, shorter than at 59% of the 182 Wisconsin stations; it reaches 173 days one year in ten and falls short of 130 one year in ten. On average 169 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 18, and return around September 26. Severe cold of 16°F or below comes every winter, usually between November 19 and March 26.

July is the warmest month at Baraboo, WI, averaging 83°F by day and 60°F at night; January is the coldest at 28°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 65% of years.

Warmth for growing adds up to 2,625 growing degree days a year (base 50°F), more than at 74% of the 182 Wisconsin stations. 33% of them (879) have built up by the end of June, and July adds the most, 665. Precipitation totals 39.1 inches a year, most in June (5.6") and least in January (1.4"); May to September bring 59% of it.

The nearest other station, Wisconsin Dells, WI, 9 miles north of Baraboo, has a last frost 3 days later (May 8), a first frost 2 days earlier (October 3), a season 6 days shorter.

The first measurable snow (0.1 inch or more) in Baraboo usually arrives around November 22, and the last of the season around March 27. Those are the middle dates across the winters of 1991–2020 at Baraboo, WI, 2 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 39 days after the last snow.

ZIP 53913 is 2 miles from Baraboo, WI, which stands at 823 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 53913 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.