Mosquito season in Kane County, IL: when it starts and ends
Mosquito months in Kane County
In a normal year mosquito season in Kane County, IL starts around April 19 and ends around October 20, about 26 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Kane County, and when
- Start tipping out standing water weekly by April 5.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 20.
- 35 West Nile cases since 2016: you should wear EPA-registered repellent at dusk July to August, and check IL spray notices.
Kane County against the rest of IL
Kane County has the 91st longest season of 102 IL counties, at 184 days against 232 in Pulaski County and 174 in Boone County. Its mean temperature is 49.4°F.
- DuPage County: April 18 to October 22 (187 days, 99 WNV)
- Kendall County: April 18 to October 21 (186 days, 4 WNV)
- Ogle County: April 19 to October 19 (183 days, 1 WNV)
- Lake County: April 22 to October 22 (183 days, 41 WNV)
West Nile in Kane County
From 1999 to 2025, CDC ArboNET counted 109 human West Nile cases in Kane County (66 neuroinvasive) across 19 years. The worst was 2005 with 18; the latest was 2025.
See how the dates are worked out, and reading the West Nile counts.