Mosquito season in Steele County, MN: when it starts and ends
Mosquito months in Steele County
In a normal year mosquito season in Steele County, MN starts around April 28 and ends around October 11, about 24 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Steele County, and when
- Start tipping out standing water weekly by April 14.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 11.
- 3 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to July, more so if over 60.
Steele County against the rest of MN
Steele County has the 19th longest season of 87 MN counties, at 167 days against 176 in Winona County and 118 in Cook County. Its mean temperature is 44.8°F.
- Morrison County: April 27 to October 10 (167 days, 2 WNV)
- Washington County: April 27 to October 11 (167 days, 5 WNV)
- Lyon County: April 27 to October 11 (166 days, 18 WNV)
- Redwood County: April 27 to October 10 (166 days, 9 WNV)
West Nile in Steele County
From 1999 to 2025, CDC ArboNET counted 5 human West Nile cases in Steele County (4 neuroinvasive) across 5 years. The worst was 2025 with 1; the latest was 2025.
Background: when the season starts across the US; how the dates are worked out.