Mosquito season in Sumner County, TN: when it starts and ends
Mosquito months in Sumner County
In a normal year mosquito season in Sumner County, TN starts around March 26 and ends around November 9, about 33 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Sumner County, and when
- Start tipping out standing water weekly by March 12.
- Book any yard treatment for late March, ahead of the July peak.
- Repellent can go away after November 9.
- 5 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to September, more so if over 60.
Sumner County against the rest of TN
Sumner County has the 32nd longest season of 95 TN counties, at 228 days against 252 in Hamilton County and 186 in Carter County. Its mean temperature is 57.8°F.
- Lewis County: March 25 to November 10 (230 days, 0 WNV)
- Henderson County: March 24 to November 8 (229 days, 1 WNV)
- McMinn County: March 27 to November 10 (228 days, 1 WNV)
- Houston County: March 28 to November 11 (228 days, 0 WNV)
West Nile in Sumner County
From 1999 to 2025, CDC ArboNET counted 7 human West Nile cases in Sumner County (4 neuroinvasive) across 6 years. The worst was 2016 with 2; the latest was 2025.
See how the dates are worked out, and reading the West Nile counts.