Mosquito season in Wyoming County, PA: when it starts and ends

Mosquito months in Wyoming County

In a normal year mosquito season in Wyoming County, PA starts around May 1 and ends around October 13, about 24 weeks.

1. Jan
2. Feb
3. Mar
4. Apr
5. May
6. Jun
7. Jul
8. Aug
9. Sep
10. Oct
11. Nov
12. Dec

What to do in Wyoming County, and when

• Start tipping out standing water weekly by April 17.
• Book any yard treatment for early May, ahead of the July peak.
• Repellent can go away after October 13.
• No West Nile cases since 2016, so bites in Wyoming County are a nuisance; check window screens.

Wyoming County against the rest of PA

Wyoming County has the 55th longest season of 67 PA counties, at 165 days against 222 in Philadelphia County and 154 in Clinton County. Its mean temperature is 47.1°F.

• Somerset County: April 30 to October 12 (165 days, 2 WNV)
• Tioga County: April 30 to October 12 (165 days, 2 WNV)
• Forest County: May 2 to October 13 (164 days, 0 WNV)
• Mercer County: May 3 to October 13 (163 days, 0 WNV)

West Nile in Wyoming County

CDC ArboNET lists no human West Nile cases for Wyoming County from 1999 to 2025, though virus turned up in birds, mosquitoes or horses in 10 of those years.

Background: when the season starts across the US; how the dates are worked out.