Mosquito season in Dunn County, WI: when it starts and ends
Mosquito months in Dunn County
In a normal year mosquito season in Dunn County, WI starts around April 30 and ends around October 9, about 23 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Dunn County, and when
- Start tipping out standing water weekly by April 16.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 9.
- 2 West Nile cases since 2016 (last 2024): you should use repellent at dusk July to July, more so if over 60.
Dunn County against the rest of WI
Dunn County has the 35th longest season of 72 WI counties, at 162 days against 180 in La Crosse County and 139 in Rusk County. Its mean temperature is 44.1°F.
- Monroe County: April 29 to October 8 (162 days, 2 WNV)
- Chippewa County: April 30 to October 9 (162 days, 2 WNV)
- Pepin County: April 30 to October 9 (162 days, 1 WNV)
- Waupaca County: April 30 to October 9 (162 days, 0 WNV)
West Nile in Dunn County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Dunn County (1 neuroinvasive) across 2 years. The worst was 2024 with 1; the latest was 2024.
Background: when the season starts across the US; how the dates are worked out.