Mosquito season in Woodford County, IL: when it starts and ends
Mosquito months in Woodford County
In a normal year mosquito season in Woodford County, IL starts around April 15 and ends around October 25, about 28 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Woodford 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 25.
- 3 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.
Woodford County against the rest of IL
Woodford County has the 77th longest season of 102 IL counties, at 193 days against 232 in Pulaski County and 174 in Boone County. Its mean temperature is 51.6°F.
- Rock Island County: April 13 to October 23 (193 days, 3 WNV)
- Iroquois County: April 14 to October 24 (193 days, 0 WNV)
- Warren County: April 13 to October 22 (192 days, 1 WNV)
- McLean County: April 14 to October 23 (192 days, 4 WNV)
West Nile in Woodford County
From 1999 to 2025, CDC ArboNET counted 8 human West Nile cases in Woodford County (3 neuroinvasive) across 5 years. The worst was 2023 with 2; the latest was 2025.
More: how the dates are worked out · when the season starts across the US.