It’s Almost Time for First Fall Frost in Illinois
| Jim Angel - (217) 333-0729, Fax: (217) 244-0220, firstname.lastname@example.org
Eva Kingston - (217) 244-7270, Fax: (217) 333-6540, email@example.com
“The first fall frost usually occurs between October 7 (northern Illinois), October 14 (central Illinois), and October 21 (southern Illinois). The Chicago area can expect frost by October 14, a week later than the rest of northern Illinois, probably a result of the warmer urban setting and the moderating influence of Lake Michigan,” says State Climatologist Jim Angel of the Illinois State Water Survey (http://www.sws.uiuc.edu), a division of the Illinois Department of Natural Resources.
The average frost date is based on 1971-2000 averages. Although the actual date varies quite a bit from year to year, “ frost usually occurs within two weeks of the dates shown on the map,” says Angel.
“Despite concerns about global warming, the first fall frost date has been occurring a little earlier at most Illinois locations since the early 1970s, suggesting somewhat cooler fall conditions,” says Angel.
Data from 13 long-term cooperative observer sites in more rural locations throughout Illinois indicate that the frost date is 16 days earlier in McLeansboro; 14 days earlier in Anna and Champaign-Urbana; 9 days earlier in Hoopeston and Windsor; 7 days earlier in Sparta; and 5 days earlier in Marengo, Walnut, and Minonk. This pattern appears to be prevalent across Illinois, except for a slight trend toward frost 3 days later in Carlinville (west-central), 1 day later in Rushville (northeast), and no change in Mt. Carroll and Aledo.
“There’s a good chance that Indian Summer, a warm, dry spell after the first fall frost, will occur this year. If so, more mild weather will follow,” concludes Angel.