Mosquito season in Chippewa County, MN: when it starts and ends
Mosquito months in Chippewa County
In a normal year mosquito season in Chippewa County, MN starts around April 27 and ends around October 10, about 24 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Chippewa County, and when
- Start tipping out standing water weekly by April 13.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 10.
- 3 West Nile cases since 2016 (last 2023): you should use repellent at dusk July to July, more so if over 60.
Chippewa County against the rest of MN
Chippewa County has the 22nd longest season of 87 MN counties, at 165 days against 176 in Winona County and 118 in Cook County. Its mean temperature is 44.3°F.
- Lyon County: April 27 to October 11 (166 days, 18 WNV)
- Redwood County: April 27 to October 10 (166 days, 9 WNV)
- Isanti County: April 27 to October 9 (165 days, 1 WNV)
- McLeod County: April 27 to October 10 (165 days, 4 WNV)
West Nile in Chippewa County
From 1999 to 2025, CDC ArboNET counted 13 human West Nile cases in Chippewa County (6 neuroinvasive) across 9 years. The worst was 2012 with 4; the latest was 2023.
More: how the dates are worked out · when mosquitoes go away for the winter.