Mosquito season in Union County, KY: when it starts and ends
Mosquito months in Union County
In a normal year mosquito season in Union County, KY starts around March 26 and ends around November 5, about 32 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Union 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 5.
- No West Nile cases since 2016, so bites in Union County are a nuisance; check window screens.
Union County against the rest of KY
Union County has the 21st longest season of 120 KY counties, at 224 days against 249 in Lyon County and 180 in Shelby County. Its mean temperature is 56.7°F.
- Daviess County: March 24 to November 6 (226 days, 6 WNV)
- Todd County: March 25 to November 6 (226 days, 0 WNV)
- Hancock County: March 28 to November 7 (224 days, 0 WNV)
- Barren County: March 28 to November 5 (222 days, 2 WNV)
West Nile in Union County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Union County (2 neuroinvasive) across 1 year. The worst was 2002 with 2; the latest was 2002.
Background: when the season starts across the US; how the dates are worked out.