Mosquito season in Oneida County, WI: when it starts and ends
Mosquito months in Oneida County
In a normal year mosquito season in Oneida County, WI starts around May 13 and ends around October 1, about 20 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Oneida County, and when
- Start tipping out standing water weekly by April 29.
- Book any yard treatment for mid May, ahead of the July peak.
- Repellent can go away after October 1.
- No West Nile cases since 2016, so bites in Oneida County are a nuisance; check window screens.
Oneida County against the rest of WI
Oneida County has the 70th longest season of 72 WI counties, at 141 days against 180 in La Crosse County and 139 in Rusk County. Its mean temperature is 40.8°F.
- Forest County: May 10 to September 29 (141 days, 0 WNV)
- Florence County: May 11 to September 29 (141 days, 0 WNV)
- Vilas County: May 12 to September 29 (140 days, 1 WNV)
- Rusk County: May 15 to October 1 (139 days, 1 WNV)
West Nile in Oneida County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Oneida County (1 neuroinvasive) across 1 year. The worst was 2015 with 1; the latest was 2015.
See how the dates are worked out, and when mosquitoes go away for the winter.