Frost Dates for 62363 — Pittsfield, Illinois

Half of springs at Pittsfield #2, IL see their last 32°F night by April 14; only one in ten is past it by March 31, and one in ten still has one after April 30. Planting tender crops after April 21 leaves a 30% risk of a frost on them, after April 25 20%, and after April 30 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 22% of the 158 Illinois stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 21 in half of years, as early as October 5 one year in ten, and holds off past November 3 one year in ten. A hard freeze of 28°F follows 11 days later, around November 1; in spring the one-in-ten date for 28°F is April 20, 10 days before the 32°F one. The freeze-free season lasts 189 days in a typical year, longer than at 62% of the 158 Illinois stations; it reaches 209 days one year in ten and falls short of 167 one year in ten. On average 119 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 April 26, and return around October 11. Severe cold of 16°F or below comes every winter, usually between December 4 and March 6.

July is the warmest month at Pittsfield #2, IL, averaging 88°F by day and 66°F at night; January is the coldest at 37°F and 19°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 88% of years.

Warmth for growing adds up to 3,847 growing degree days a year (base 50°F), more than at 76% of the 158 Illinois stations. 37% of them (1,424) have built up by the end of June, and July adds the most, 831. Precipitation totals 40.3 inches a year, most in June (5.0") and least in January (2.0"); May to September bring 52% of it.

The nearest other station, Perry 6 NW, IL, 14 miles north of Pittsfield, has a last frost 4 days later (April 18), a first frost 6 days earlier (October 15), a season 10 days shorter.

The first measurable snow (0.1 inch or more) in Pittsfield usually arrives around December 4, and the last of the season around March 1. Those are the middle dates across the winters of 1991–2020 at Pittsfield #2, IL, 1.3 miles away: half of years saw snow earlier, half later. Snow fell in 95% of those winters. The last 32°F night of spring typically comes 44 days after the last snow.

ZIP 62363 is 1 mile from Pittsfield #2, IL, which stands at 670 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 62363 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°C) over 1991–2020; a zone describes winter lows, not frost dates.