Mosquito season in Madison County, NY: when it starts and ends
Mosquito months in Madison County
In a normal year mosquito season in Madison County, NY starts around May 3 and ends around October 9, about 23 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Madison County, and when
- Start tipping out standing water weekly by April 19.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 9.
- No West Nile cases since 2016, so bites in Madison County are a nuisance; check window screens.
Madison County against the rest of NY
Madison County has the 49th longest season of 62 NY counties, at 159 days against 218 in New York County and 125 in Franklin County. Its mean temperature is 44.9°F.
- St. Lawrence County: May 2 to October 9 (160 days, 3 WNV)
- Cattaraugus County: May 3 to October 10 (160 days, 1 WNV)
- Cortland County: May 4 to October 9 (158 days, 0 WNV)
- Delaware County: May 5 to October 10 (158 days, 0 WNV)
West Nile in Madison County
CDC ArboNET lists no human West Nile cases for Madison County from 1999 to 2025, though virus turned up in birds, mosquitoes or horses in 13 of those years.
More: how the dates are worked out · when mosquitoes go away for the winter.