Frost Dates for 62691 — Virginia, Illinois

Half of springs at Jacksonville 2E, IL see their last 32°F night by April 19; only one in ten is past it by April 5, and one in ten still has one after May 5. Planting tender crops after April 26 leaves a 30% risk of a frost on them, after April 30 20%, and after May 5 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 17 in half of years, as early as October 1 one year in ten, and holds off past October 29 one year in ten. A hard freeze of 28°F follows 10 days later, around October 27; in spring the one-in-ten date for 28°F is April 23, 12 days before the 32°F one. The freeze-free season lasts 179 days in a typical year, shorter than at 65% of the 158 Illinois stations; it reaches 199 days one year in ten and falls short of 157 one year in ten. On average 128 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 6. Severe cold of 16°F or below comes every winter, usually between December 1 and March 9.

July is the warmest month at Jacksonville 2E, IL, averaging 87°F by day and 64°F at night; January is the coldest at 36°F and 18°F. A freezing night is all but certain in every month from October 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 17% of years.

Warmth for growing adds up to 3,570 growing degree days a year (base 50°F), more than at 56% of the 158 Illinois stations. 36% of them (1,294) have built up by the end of June, and July adds the most, 783. Precipitation totals 39.3 inches a year, most in June (4.9") and least in February (1.7"); May to September bring 52% of it.

The nearest other station, Jacksonville 2, IL, 17 miles south of Virginia, has a last frost 2 days earlier (April 17), a first frost 4 days later (October 21), a season 7 days longer.

The first measurable snow (0.1 inch or more) in Virginia usually arrives around December 7, and the last of the season around March 14. Those are the middle dates across the winters of 1991–2020 at Virginia, IL, 0.3 miles away: half of years saw snow earlier, half later. Snow fell in 96% of those winters. The last 32°F night of spring typically comes 36 days after the last snow.

ZIP 62691 is 15 miles from Jacksonville 2E, IL, which stands at 610 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 62691 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.