Mosquito season in Steele County, ND: when it starts and ends
Mosquito months in Steele County
In a normal year mosquito season in Steele County, ND starts around May 7 and ends around September 30, about 21 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 23.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after September 30.
- 2 West Nile cases since 2016 (last 2021): you should use repellent at dusk July, more so if over 60.
Steele County against the rest of ND
Steele County has the 35th longest season of 53 ND counties, at 146 days against 160 in Sheridan County and 135 in Rolette County. Its mean temperature is 39.1°F.
- Stark County: May 8 to October 2 (147 days, 21 WNV)
- Ramsey County: May 7 to September 30 (146 days, 12 WNV)
- Nelson County: May 7 to September 30 (145 days, 1 WNV)
- Pierce County: May 7 to September 29 (145 days, 4 WNV)
West Nile in Steele County
From 1999 to 2025, CDC ArboNET counted 7 human West Nile cases in Steele County (3 neuroinvasive) across 4 years. The worst was 2012 with 3; the latest was 2021.
Background: when mosquitoes go away for the winter; how the dates are worked out.