Mosquito season in Switzerland County, IN: when it starts and ends
Mosquito months in Switzerland County
In a normal year mosquito season in Switzerland County, IN starts around April 4 and ends around November 2, about 30 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Switzerland County, and when
- Start tipping out standing water weekly by March 21.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after November 2.
- No West Nile cases since 2016, so bites in Switzerland County are a nuisance; check window screens.
Switzerland County against the rest of IN
Switzerland County has the 17th longest season of 92 IN counties, at 212 days against 231 in Floyd County and 177 in Steuben County. Its mean temperature is 55.1°F.
- Gibson County: April 2 to November 1 (213 days, 0 WNV)
- Vigo County: April 1 to October 30 (212 days, 0 WNV)
- Crawford County: April 3 to October 31 (211 days, 1 WNV)
- Washington County: April 4 to November 1 (211 days, 0 WNV)
West Nile in Switzerland County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Switzerland County (1 neuroinvasive) across 1 year. The worst was 2003 with 1; the latest was 2003.
More: how the dates are worked out · when mosquitoes go away for the winter.