Mosquito season in Columbiana County, OH: when it starts and ends
Mosquito months in Columbiana County
In a normal year mosquito season in Columbiana County, OH starts around April 20 and ends around October 22, about 26 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Columbiana County, and when
- Start tipping out standing water weekly by April 6.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 22.
- 3 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to August, more so if over 60.
Columbiana County against the rest of OH
Columbiana County has the 75th longest season of 88 OH counties, at 185 days against 209 in Gallia County and 177 in Ashtabula County. Its mean temperature is 50.2°F.
- Wayne County: April 18 to October 20 (185 days, 4 WNV)
- Carroll County: April 20 to October 22 (185 days, 0 WNV)
- Adams County: April 20 to October 21 (184 days, 0 WNV)
- Brown County: April 20 to October 21 (184 days, 0 WNV)
West Nile in Columbiana County
From 1999 to 2025, CDC ArboNET counted 4 human West Nile cases in Columbiana County (2 neuroinvasive) across 4 years. The worst was 2025 with 1; the latest was 2025.
See how the dates are worked out, and when mosquitoes go away for the winter.