Mosquito season in Greene County, OH: when it starts and ends
Mosquito months in Greene County
In a normal year mosquito season in Greene County, OH starts around April 5 and ends around October 30, about 30 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Greene County, and when
- Start tipping out standing water weekly by March 22.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 30.
- 1 West Nile case since 2016 (last 2017): you should use repellent at dusk June to August, more so if over 60.
Greene County against the rest of OH
Greene County has the 3rd longest season of 88 OH counties, at 208 days against 209 in Gallia County and 177 in Ashtabula County. Its mean temperature is 53.4°F.
- Gallia County: April 4 to October 30 (209 days, 0 WNV)
- Pickaway County: April 5 to October 31 (209 days, 1 WNV)
- Hamilton County: April 5 to October 30 (208 days, 13 WNV)
- Washington County: April 6 to October 29 (207 days, 0 WNV)
West Nile in Greene County
From 1999 to 2025, CDC ArboNET counted 5 human West Nile cases in Greene County (1 neuroinvasive) across 3 years. The worst was 2006 with 2; the latest was 2017.
More: how the dates are worked out · when the season starts across the US.