Frost Dates for 60089 — Buffalo Grove, Illinois

Half of springs at Chicago Palwaukee Airport, IL see their last 32°F night by April 19; only one in ten is past it by April 4, and one in ten still has one after May 3. Planting tender crops after April 25 leaves a 30% risk of a frost on them, after April 28 20%, and after May 3 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 82% of the 158 Illinois stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 26 in half of years, as early as October 13 one year in ten, and holds off past November 9 one year in ten. A hard freeze of 28°F follows 12 days later, around November 7; in spring the one-in-ten date for 28°F is April 20, 13 days before the 32°F one. The freeze-free season lasts 190 days in a typical year, longer than at 66% of the 158 Illinois stations; it reaches 207 days one year in ten and falls short of 170 one year in ten. On average 122 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 11 days longer, to about April 30, and return around October 16. Severe cold of 16°F or below comes every winter, usually between December 5 and March 6.

July is the warmest month at Chicago Palwaukee Airport, IL, averaging 84°F by day and 66°F at night; January is the coldest at 32°F and 18°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 15% of years.

Warmth for growing adds up to 3,201 growing degree days a year (base 50°F), fewer than at 73% of the 158 Illinois stations. 32% of them (1,029) have built up by the end of June, and July adds the most, 772. Precipitation totals 32.3 inches a year, most in June (4.0") and least in January (1.3"); May to September bring 55% of it.

The nearest other station, Mundelein 4 WSW, IL, 8 miles northwest of Buffalo Grove and 204 feet higher, has a last frost 10 days later (April 29), a first frost 6 days earlier (October 20), a season 18 days shorter.

The first measurable snow (0.1 inch or more) in Buffalo Grove usually arrives around November 23, and the last of the season around April 6. Those are the middle dates across the winters of 1991–2020 at Mundelein 4 WSW, IL, 8.4 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 13 days after the last snow.

ZIP 60089 is 4 miles from Chicago Palwaukee Airport, IL, which stands at 636 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 9 other ZIP codes share the station; its figures are presented in full for 60056 (Mount Prospect). The 2023 USDA Plant Hardiness Zone Map lists ZIP 60089 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.