Mosquito season in Henry County, OH: when it starts and ends
Mosquito months in Henry County
In a normal year mosquito season in Henry County, OH starts around April 18 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 4.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 23.
- 1 West Nile case since 2016 (last 2024): you should use repellent at dusk June to August, more so if over 60.
Henry County against the rest of OH
Henry County has the 62nd longest season of 88 OH counties, at 188 days against 209 in Gallia County and 177 in Ashtabula County. Its mean temperature is 50.3°F.
- Sandusky County: April 18 to October 24 (189 days, 1 WNV)
- Noble County: April 19 to October 25 (189 days, 1 WNV)
- Paulding County: April 18 to October 23 (188 days, 1 WNV)
- Hocking County: April 19 to October 24 (188 days, 0 WNV)
West Nile in Henry County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Henry County (3 neuroinvasive) across 3 years. The worst was 2024 with 1; the latest was 2024.
See how the dates are worked out, and when the season starts across the US.