Mosquito season in Champaign County, OH: when it starts and ends
Mosquito months in Champaign County
In a normal year mosquito season in Champaign County, OH starts around April 14 and ends around October 23, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Champaign County, and when
- Start tipping out standing water weekly by March 31.
- 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 Champaign County are a nuisance; check window screens.
Champaign County against the rest of OH
Champaign County has the 40th longest season of 88 OH counties, at 192 days against 209 in Gallia County and 177 in Ashtabula County. Its mean temperature is 51.2°F.
- Putnam County: April 15 to October 24 (193 days, 1 WNV)
- Lorain County: April 16 to October 26 (193 days, 3 WNV)
- Harrison County: April 14 to October 23 (192 days, 0 WNV)
- Clark County: April 15 to October 24 (192 days, 5 WNV)
West Nile in Champaign County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Champaign County (3 neuroinvasive) across 2 years. The worst was 2003 with 2; the latest was 2003.
More: how the dates are worked out · when the season starts across the US.