Mosquito season in Dutchess County, NY: when it starts and ends
Mosquito months in Dutchess County
In a normal year mosquito season in Dutchess County, NY starts around April 22 and ends around October 17, about 25 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Dutchess County, and when
- Start tipping out standing water weekly by April 8.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 17.
- 8 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to July, more so if over 60.
Dutchess County against the rest of NY
Dutchess County has the 17th longest season of 62 NY counties, at 177 days against 218 in New York County and 125 in Franklin County. Its mean temperature is 48.7°F.
- Columbia County: April 22 to October 18 (179 days, 2 WNV)
- Monroe County: April 25 to October 20 (179 days, 13 WNV)
- Yates County: April 26 to October 19 (176 days, 0 WNV)
- Niagara County: April 27 to October 21 (176 days, 5 WNV)
West Nile in Dutchess County
From 1999 to 2025, CDC ArboNET counted 13 human West Nile cases in Dutchess County (9 neuroinvasive) across 9 years. The worst was 2012 with 3; the latest was 2025.
See how the dates are worked out, and reading the West Nile counts.