Mosquito season in Bronx County, NY: when it starts and ends
Mosquito months in Bronx County
In a normal year mosquito season in Bronx County, NY starts around April 6 and ends around November 9, about 31 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Bronx County, and when
- Start tipping out standing water weekly by March 23.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after November 9.
- 17 West Nile cases since 2016: you should wear EPA-registered repellent at dusk June to August, and check NY spray notices.
Bronx County against the rest of NY
Bronx County has the 2nd longest season of 62 NY counties, at 216 days against 218 in New York County and 125 in Franklin County. Its mean temperature is 55.9°F.
- New York County: April 4 to November 9 (218 days, 38 WNV)
- Kings County: April 7 to November 9 (216 days, 65 WNV)
- Nassau County: April 7 to November 8 (215 days, 113 WNV)
West Nile in Bronx County
From 1999 to 2025, CDC ArboNET counted 67 human West Nile cases in Bronx County (59 neuroinvasive) across 20 years. The worst was 1999 with 10; the latest was 2025.
See how the dates are worked out, and reading the West Nile counts.