Mosquito season in Stark County, IL: when it starts and ends
Mosquito months in Stark County
In a normal year mosquito season in Stark County, IL starts around April 15 and ends around October 21, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Stark County, and when
- Start tipping out standing water weekly by April 1.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 21.
- No West Nile cases since 2016, so bites in Stark County are a nuisance; check window screens.
Stark County against the rest of IL
Stark County has the 86th longest season of 102 IL counties, at 189 days against 232 in Pulaski County and 174 in Boone County. Its mean temperature is 50°F.
- Will County: April 16 to October 23 (190 days, 34 WNV)
- Mercer County: April 15 to October 21 (189 days, 1 WNV)
- Cook County: April 20 to October 26 (189 days, 532 WNV)
- Bureau County: April 15 to October 20 (188 days, 0 WNV)
West Nile in Stark County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Stark County (1 neuroinvasive) across 1 year. The worst was 2002 with 1; the latest was 2002.
Background: when mosquitoes go away for the winter; how the dates are worked out.