Mosquito season in Fayette County, PA: when it starts and ends
Mosquito months in Fayette County
In a normal year mosquito season in Fayette County, PA starts around May 5 and ends around October 10, about 23 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Fayette County, and when
- Start tipping out standing water weekly by April 21.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 10.
- 3 West Nile cases since 2016 (last 2025): you should use repellent at dusk July, more so if over 60.
Fayette County against the rest of PA
Fayette County has the 65th longest season of 67 PA counties, at 158 days against 222 in Philadelphia County and 154 in Clinton County. Its mean temperature is 48.6°F.
- Sullivan County: May 2 to October 8 (158 days, 0 WNV)
- Potter County: May 3 to October 8 (158 days, 1 WNV)
- Warren County: May 8 to October 11 (156 days, 0 WNV)
- Clinton County: May 7 to October 8 (154 days, 2 WNV)
West Nile in Fayette County
From 1999 to 2025, CDC ArboNET counted 8 human West Nile cases in Fayette County (6 neuroinvasive) across 7 years. The worst was 2005 with 2; the latest was 2025.
More: how the dates are worked out · when the season starts across the US.