Mosquito season in Richland County, SC: when it starts and ends
Mosquito months in Richland County
In a normal year mosquito season in Richland County, SC starts around February 24 and ends around December 4, about 40 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Richland County, and when
- Start tipping out standing water weekly by February 10.
- Book any yard treatment for late February, ahead of the July peak.
- Repellent can go away after December 4.
- 10 West Nile cases since 2016: you should wear EPA-registered repellent at dusk May to September, and check SC spray notices.
Richland County against the rest of SC
Richland County has the 7th longest season of 46 SC counties, at 283 days against 349 in Charleston County and 209 in Cherokee County. Its mean temperature is 65.4°F.
- Berkeley County: February 22 to December 13 (294 days, 1 WNV)
- Georgetown County: February 25 to December 10 (288 days, 1 WNV)
- Calhoun County: February 23 to December 2 (282 days, 0 WNV)
- Horry County: February 28 to December 7 (282 days, 11 WNV)
West Nile in Richland County
From 1999 to 2025, CDC ArboNET counted 16 human West Nile cases in Richland County (13 neuroinvasive) across 8 years. The worst was 2022 with 4; the latest was 2024.
Background: reading the West Nile counts; how the dates are worked out.