Frost Dates for 53105 — Burlington, Wisconsin

Half of springs at Burlington, 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 23. Planting tender crops after May 11 leaves a 30% risk of a frost on them, after May 16 20%, and after May 23 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 96% of the 182 Wisconsin stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 9 in half of years, as early as September 24 one year in ten, and holds off past October 24 one year in ten. A hard freeze of 28°F follows 13 days later, around October 22; in spring the one-in-ten date for 28°F is May 11, 12 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 177 days one year in ten and falls short of 134 one year in ten. On average 155 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 21 and March 22.

July is the warmest month at Burlington, WI, averaging 81°F by day and 59°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 65% of years.

Warmth for growing adds up to 2,417 growing degree days a year (base 50°F), fewer than at 51% of the 182 Wisconsin stations. 31% of them (756) have built up by the end of June, and July adds the most, 625. Precipitation totals 35.6 inches a year, most in June (4.5") and least in January (1.8"); May to September bring 54% of it.

The nearest other station, Rochester Wwtp, WI, 5 miles northeast of Burlington, has the same 50% last-frost date, a first frost 1 day later (October 10).

The first measurable snow (0.1 inch or more) in Burlington usually arrives around November 25, and the last of the season around March 31. Those are the middle dates across the winters of 1991–2020 at Burlington, WI, 1.6 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 35 days after the last snow.

ZIP 53105 is 2 miles from Burlington, WI, which stands at 751 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 53105 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.