Mosquito season in Logan County, IL: when it starts and ends
Mosquito months in Logan County
In a normal year mosquito season in Logan County, IL starts around April 8 and ends around October 25, about 29 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Logan County, and when
- Start tipping out standing water weekly by March 25.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 25.
- No West Nile cases since 2016, so bites in Logan County are a nuisance; check window screens.
Logan County against the rest of IL
Logan County has the 61st longest season of 102 IL counties, at 200 days against 232 in Pulaski County and 174 in Boone County. Its mean temperature is 52.2°F.
- Tazewell County: April 8 to October 26 (201 days, 7 WNV)
- Menard County: April 9 to October 26 (201 days, 0 WNV)
- Champaign County: April 9 to October 26 (200 days, 5 WNV)
- Peoria County: April 9 to October 25 (199 days, 12 WNV)
West Nile in Logan County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Logan County (1 neuroinvasive) across 2 years. The worst was 2013 with 1; the latest was 2013.
Background: when mosquitoes go away for the winter; how the dates are worked out.