Mosquito season in Ashland County, WI: when it starts and ends
Mosquito months in Ashland County
In a normal year mosquito season in Ashland County, WI starts around May 13 and ends around October 3, about 21 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Ashland 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 3.
- No West Nile cases since 2016, so bites in Ashland County are a nuisance; check window screens.
Ashland County against the rest of WI
Ashland County has the 65th longest season of 72 WI counties, at 144 days against 180 in La Crosse County and 139 in Rusk County. Its mean temperature is 41.4°F.
- Price County: May 9 to October 1 (145 days, 1 WNV)
- Bayfield County: May 11 to October 3 (145 days, 1 WNV)
- Iron County: May 11 to September 30 (143 days, 0 WNV)
- Marinette County: May 14 to October 3 (142 days, 1 WNV)
West Nile in Ashland County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Ashland County (0 neuroinvasive) across 1 year. The worst was 2014 with 1; the latest was 2014.
More: how the dates are worked out · when the season starts across the US.