Mosquito season in Kingsbury County, SD: when it starts and ends

Mosquito months in Kingsbury County

In a normal year mosquito season in Kingsbury County, SD starts around April 29 and ends around October 8, about 23 weeks.

1. Jan
2. Feb
3. Mar
4. Apr
5. May
6. Jun
7. Jul
8. Aug
9. Sep
10. Oct
11. Nov
12. Dec

What to do in Kingsbury County, and when

• Start tipping out standing water weekly by April 15.
• Book any yard treatment for late April, ahead of the July peak.
• Repellent can go away after October 8.
• 17 West Nile cases since 2016: you should wear EPA-registered repellent at dusk July to July, and check SD spray notices.

Kingsbury County against the rest of SD

Kingsbury County has the 32nd longest season of 66 SD counties, at 161 days against 179 in Yankton County and 139 in Lawrence County. Its mean temperature is 44°F.

• McCook County: April 29 to October 8 (162 days, 9 WNV)
• Roberts County: April 29 to October 8 (162 days, 5 WNV)
• Perkins County: May 1 to October 9 (161 days, 1 WNV)
• Bennett County: May 2 to October 10 (161 days, 1 WNV)

West Nile in Kingsbury County

From 1999 to 2025, CDC ArboNET counted 48 human West Nile cases in Kingsbury County (7 neuroinvasive) across 16 years. The worst was 2003 with 11; the latest was 2024.

See how the dates are worked out, and reading the West Nile counts.