Mosquito season in Potter County, SD: when it starts and ends
Mosquito months in Potter County
In a normal year mosquito season in Potter County, SD starts around May 1 and ends around October 7, about 23 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Potter County, and when
- Start tipping out standing water weekly by April 17.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 7.
- 9 West Nile cases since 2016 (last 2024): you should use repellent at dusk July to August, more so if over 60.
Potter County against the rest of SD
Potter County has the 42nd longest season of 66 SD counties, at 160 days against 179 in Yankton County and 139 in Lawrence County. Its mean temperature is 44.3°F.
- Grant County: May 1 to October 8 (160 days, 7 WNV)
- Marshall County: May 1 to October 8 (160 days, 10 WNV)
- Pennington County: May 2 to October 9 (160 days, 32 WNV)
- Brown County: April 30 to October 6 (159 days, 71 WNV)
West Nile in Potter County
From 1999 to 2025, CDC ArboNET counted 29 human West Nile cases in Potter County (7 neuroinvasive) across 11 years. The worst was 2003 with 14; the latest was 2024.
Background: reading the West Nile counts; how the dates are worked out.