Mosquito season in Anderson County, SC: when it starts and ends

Mosquito months in Anderson County

In a normal year mosquito season in Anderson County, SC starts around March 11 and ends around November 24, about 37 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 Anderson County, and when

• Start tipping out standing water weekly by February 25.
• Book any yard treatment for mid March, ahead of the July peak.
• Repellent can go away after November 24.
• 5 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to September, more so if over 60.

Anderson County against the rest of SC

Anderson County has the 22nd longest season of 46 SC counties, at 258 days against 349 in Charleston County and 209 in Cherokee County. Its mean temperature is 61.9°F.

• Kershaw County: March 11 to November 27 (261 days, 1 WNV)
• Clarendon County: March 9 to November 24 (260 days, 0 WNV)
• Greenwood County: March 12 to November 25 (258 days, 3 WNV)
• Marlboro County: March 12 to November 21 (254 days, 1 WNV)

West Nile in Anderson County

From 1999 to 2025, CDC ArboNET counted 8 human West Nile cases in Anderson County (7 neuroinvasive) across 5 years. The worst was 2012 with 3; the latest was 2025.

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