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

Mosquito months in Spartanburg County

In a normal year mosquito season in Spartanburg County, SC starts around March 24 and ends around November 11, about 33 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 Spartanburg County, and when

• Start tipping out standing water weekly by March 10.
• Book any yard treatment for late March, ahead of the July peak.
• Repellent can go away after November 11.
• 4 West Nile cases since 2016 (last 2024): you should use repellent at dusk June to September, more so if over 60.

Spartanburg County against the rest of SC

Spartanburg County has the 43rd longest season of 46 SC counties, at 232 days against 349 in Charleston County and 209 in Cherokee County. Its mean temperature is 60.7°F.

• York County: March 21 to November 14 (238 days, 6 WNV)
• Chesterfield County: March 21 to November 13 (237 days, 0 WNV)
• Union County: March 24 to November 10 (231 days, 2 WNV)
• Oconee County: March 30 to November 9 (224 days, 0 WNV)

West Nile in Spartanburg County

From 1999 to 2025, CDC ArboNET counted 7 human West Nile cases in Spartanburg County (3 neuroinvasive) across 7 years. The worst was 2024 with 1; the latest was 2024.

Background: reading the West Nile counts; how the dates are worked out.