Frost Dates for 54947 — Larsen, Wisconsin

Half of springs at New London, WI see their last 32°F night by May 4; only one in ten is past it by April 21, and one in ten still has one after May 19. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 14 20%, and after May 19 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 6 in half of years, as early as September 22 one year in ten, and holds off past October 22 one year in ten. A hard freeze of 28°F follows 12 days later, around October 18; in spring the one-in-ten date for 28°F is May 9, 10 days before the 32°F one. The freeze-free season lasts 153 days in a typical year, shorter than at 57% of the 182 Wisconsin stations; it reaches 172 days one year in ten and falls short of 135 one year in ten. On average 164 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 17, and return around September 26. Severe cold of 16°F or below comes every winter, usually between November 19 and March 25.

July is the warmest month at New London, WI, averaging 81°F by day and 59°F at night; January is the coldest at 25°F and 8°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 64% of years.

Warmth for growing adds up to 2,378 growing degree days a year (base 50°F), fewer than at 58% of the 182 Wisconsin stations. 32% of them (770) have built up by the end of June, and July adds the most, 621. Precipitation totals 34.9 inches a year, most in June (4.8") and least in February (1.2"); May to September bring 58% of it.

The nearest other station, Oshkosh, WI, 13 miles southeast of Larsen, has a last frost 10 days earlier (April 24), a first frost 14 days later (October 20), a season 25 days longer.

The first measurable snow (0.1 inch or more) in Larsen usually arrives around November 21, and the last of the season around April 13. Those are the middle dates across the winters of 1991–2020 at New London, WI, 11.7 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 21 days after the last snow.

ZIP 54947 is 12 miles from New London, WI, which stands at 800 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 54961 (New London). The 2023 USDA Plant Hardiness Zone Map lists ZIP 54947 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.