Mosquito season in White County, IL: when it starts and ends
Mosquito months in White County
In a normal year mosquito season in White County, IL starts around April 3 and ends around October 28, about 30 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in White County, and when
- Start tipping out standing water weekly by March 20.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 28.
- No West Nile cases since 2016, so bites in White County are a nuisance; check window screens.
White County against the rest of IL
White County has the 36th longest season of 102 IL counties, at 208 days against 232 in Pulaski County and 174 in Boone County. Its mean temperature is 55°F.
- Richland County: April 3 to October 31 (210 days, 1 WNV)
- Crawford County: April 4 to October 30 (209 days, 0 WNV)
- Pike County: April 4 to October 30 (208 days, 0 WNV)
- Clark County: April 5 to October 30 (208 days, 0 WNV)
West Nile in White County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in White County (2 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.