Mosquito season in Nelson County, KY: when it starts and ends
Mosquito months in Nelson County
In a normal year mosquito season in Nelson County, KY starts around March 31 and ends around November 5, about 31 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Nelson County, and when
- Start tipping out standing water weekly by March 17.
- Book any yard treatment for late March, ahead of the July peak.
- Repellent can go away after November 5.
- 1 West Nile case since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.
Nelson County against the rest of KY
Nelson County has the 30th longest season of 120 KY counties, at 219 days against 249 in Lyon County and 180 in Shelby County. Its mean temperature is 56.8°F.
- Grant County: March 31 to November 6 (220 days, 0 WNV)
- Carroll County: March 29 to November 3 (219 days, 0 WNV)
- Washington County: March 31 to November 5 (219 days, 0 WNV)
- Fayette County: March 31 to November 4 (218 days, 10 WNV)
West Nile in Nelson County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Nelson County (1 neuroinvasive) across 3 years. The worst was 2025 with 1; the latest was 2025.
See how the dates are worked out, and when the season starts across the US.