Mosquito season in Juneau County, WI: when it starts and ends
Mosquito months in Juneau County
In a normal year mosquito season in Juneau County, WI starts around May 5 and ends around October 3, about 22 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Juneau County, and when
- Start tipping out standing water weekly by April 21.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 3.
- 3 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to July, more so if over 60.
Juneau County against the rest of WI
Juneau County has the 58th longest season of 72 WI counties, at 151 days against 180 in La Crosse County and 139 in Rusk County. Its mean temperature is 45.3°F.
- Manitowoc County: May 11 to October 11 (153 days, 3 WNV)
- Taylor County: May 4 to October 3 (152 days, 0 WNV)
- Douglas County: May 7 to October 4 (151 days, 3 WNV)
- Lincoln County: May 7 to October 2 (148 days, 1 WNV)
West Nile in Juneau County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Juneau County (2 neuroinvasive) across 2 years. The worst was 2017 with 2; the latest was 2025.
Background: when mosquitoes go away for the winter; how the dates are worked out.