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

Mosquito months in Lackawanna County

In a normal year mosquito season in Lackawanna County, PA starts around April 18 and ends around October 21, about 27 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 Lackawanna County, and when

• Start tipping out standing water weekly by April 4.
• Book any yard treatment for mid April, ahead of the July peak.
• Repellent can go away after October 21.
• 4 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to August, more so if over 60.

Lackawanna County against the rest of PA

Lackawanna County has the 33rd longest season of 67 PA counties, at 186 days against 222 in Philadelphia County and 154 in Clinton County. Its mean temperature is 50.2°F.

• Northumberland County: April 17 to October 21 (187 days, 4 WNV)
• Schuylkill County: April 17 to October 21 (187 days, 4 WNV)
• Lycoming County: April 19 to October 20 (184 days, 1 WNV)
• Westmoreland County: April 20 to October 21 (184 days, 3 WNV)

West Nile in Lackawanna County

From 1999 to 2025, CDC ArboNET counted 10 human West Nile cases in Lackawanna County (7 neuroinvasive) across 8 years. The worst was 2003 with 3; the latest was 2025.

See how the dates are worked out, and reading the West Nile counts.