Mosquito season in Edmunds County, SD: when it starts and ends
Mosquito months in Edmunds County
In a normal year mosquito season in Edmunds County, SD starts around May 2 and ends around October 5, about 22 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Edmunds County, and when
- Start tipping out standing water weekly by April 18.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 5.
- 10 West Nile cases since 2016: you should wear EPA-registered repellent at dusk July to July, and check SD spray notices.
Edmunds County against the rest of SD
Edmunds County has the 56th longest season of 66 SD counties, at 156 days against 179 in Yankton County and 139 in Lawrence County. Its mean temperature is 42.9°F.
- Codington County: May 2 to October 6 (157 days, 25 WNV)
- Day County: May 2 to October 6 (157 days, 10 WNV)
- Deuel County: May 3 to October 5 (155 days, 5 WNV)
- Hamlin County: May 3 to October 5 (155 days, 12 WNV)
West Nile in Edmunds County
From 1999 to 2025, CDC ArboNET counted 33 human West Nile cases in Edmunds County (6 neuroinvasive) across 14 years. The worst was 2003 with 8; the latest was 2023.
More: how the dates are worked out · reading the West Nile counts.