Mosquito season in Decatur County, TN: when it starts and ends
Mosquito months in Decatur County
In a normal year mosquito season in Decatur County, TN starts around March 20 and ends around November 8, about 33 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Decatur County, and when
- Start tipping out standing water weekly by March 6.
- Book any yard treatment for mid March, ahead of the July peak.
- Repellent can go away after November 8.
- No West Nile cases since 2016, so bites in Decatur County are a nuisance; check window screens.
Decatur County against the rest of TN
Decatur County has the 17th longest season of 95 TN counties, at 233 days against 252 in Hamilton County and 186 in Carter County. Its mean temperature is 59.7°F.
- Roane County: March 20 to November 10 (235 days, 0 WNV)
- Davidson County: March 20 to November 9 (234 days, 11 WNV)
- Carroll County: March 21 to November 9 (233 days, 1 WNV)
- Hardeman County: March 21 to November 9 (233 days, 0 WNV)
West Nile in Decatur County
CDC ArboNET lists no human West Nile cases for Decatur County from 1999 to 2025, though virus turned up in birds, mosquitoes or horses in 1 of those years.
See how the dates are worked out, and when mosquitoes go away for the winter.