Mosquito season in Fairfield County, OH: when it starts and ends
Mosquito months in Fairfield County
In a normal year mosquito season in Fairfield County, OH starts around April 15 and ends around October 24, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Fairfield 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 24.
- No West Nile cases since 2016, so bites in Fairfield County are a nuisance; check window screens.
Fairfield County against the rest of OH
Fairfield County has the 44th longest season of 88 OH counties, at 192 days against 209 in Gallia County and 177 in Ashtabula County. Its mean temperature is 52.5°F.
- Clark County: April 15 to October 24 (192 days, 5 WNV)
- Coshocton County: April 15 to October 24 (192 days, 0 WNV)
- Belmont County: April 16 to October 25 (192 days, 1 WNV)
- Lucas County: April 16 to October 25 (192 days, 11 WNV)
West Nile in Fairfield County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Fairfield County (2 neuroinvasive) across 2 years. The worst was 2015 with 1; the latest was 2015.
Background: when the season starts across the US; how the dates are worked out.