Mosquito season in Mifflin County, PA: when it starts and ends
Mosquito months in Mifflin County
In a normal year mosquito season in Mifflin County, PA starts around April 16 and ends around October 22, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Mifflin County, and when
- Start tipping out standing water weekly by April 2.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 22.
- No West Nile cases since 2016, so bites in Mifflin County are a nuisance; check window screens.
Mifflin County against the rest of PA
Mifflin County has the 23rd longest season of 67 PA counties, at 190 days against 222 in Philadelphia County and 154 in Clinton County. Its mean temperature is 50.8°F.
- Snyder County: April 14 to October 23 (193 days, 0 WNV)
- Union County: April 15 to October 23 (191 days, 1 WNV)
- Beaver County: April 17 to October 23 (189 days, 3 WNV)
- Blair County: April 17 to October 21 (188 days, 1 WNV)
West Nile in Mifflin County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Mifflin County (0 neuroinvasive) across 1 year. The worst was 2012 with 1; the latest was 2012.
More: how the dates are worked out · when mosquitoes go away for the winter.