Mosquito season in Henry County, IN: when it starts and ends
Mosquito months in Henry County
In a normal year mosquito season in Henry County, IN starts around April 15 and ends around October 23, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Henry 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 23.
- No West Nile cases since 2016, so bites in Henry County are a nuisance; check window screens.
Henry County against the rest of IN
Henry County has the 63rd longest season of 92 IN counties, at 191 days against 231 in Floyd County and 177 in Steuben County. Its mean temperature is 50.4°F.
- Ripley County: April 17 to October 26 (192 days, 1 WNV)
- Montgomery County: April 14 to October 23 (191 days, 0 WNV)
- Howard County: April 15 to October 23 (191 days, 5 WNV)
- Newton County: April 15 to October 22 (191 days, 0 WNV)
West Nile in Henry County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Henry County (2 neuroinvasive) across 2 years. The worst was 2003 with 1; the latest was 2003.
Background: when the season starts across the US; how the dates are worked out.