Mosquito season in Grant County, KY: when it starts and ends
Mosquito months in Grant County
In a normal year mosquito season in Grant County, KY starts around March 31 and ends around November 6, about 31 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Grant 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 6.
- No West Nile cases since 2016, so bites in Grant County are a nuisance; check window screens.
Grant County against the rest of KY
Grant County has the 28th longest season of 120 KY counties, at 220 days against 249 in Lyon County and 180 in Shelby County. Its mean temperature is 56.1°F.
- Webster County: March 29 to November 5 (221 days, 0 WNV)
- Mercer County: March 29 to November 4 (220 days, 0 WNV)
- Carroll County: March 29 to November 3 (219 days, 0 WNV)
- Nelson County: March 31 to November 5 (219 days, 1 WNV)
West Nile in Grant County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Grant County (2 neuroinvasive) across 2 years. The worst was 2005 with 1; the latest was 2005.
More: how the dates are worked out · when mosquitoes go away for the winter.