Mosquito season in Somerset County, NJ: when it starts and ends
Mosquito months in Somerset County
In a normal year mosquito season in Somerset County, NJ starts around April 15 and ends around October 26, about 28 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Somerset County, and when
- Start tipping out standing water weekly by April 1.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 26.
- 9 West Nile cases since 2016 (last 2024): you should use repellent at dusk July to August, more so if over 60.
Somerset County against the rest of NJ
Somerset County has the 17th longest season of 21 NJ counties, at 194 days against 217 in Cape May County and 184 in Sussex County. Its mean temperature is 52°F.
- Hunterdon County: April 13 to October 26 (195 days, 6 WNV)
- Burlington County: April 15 to October 27 (195 days, 20 WNV)
- Passaic County: April 17 to October 26 (192 days, 7 WNV)
- Morris County: April 18 to October 22 (188 days, 8 WNV)
West Nile in Somerset County
From 1999 to 2025, CDC ArboNET counted 12 human West Nile cases in Somerset County (9 neuroinvasive) across 6 years. The worst was 2018 with 4; the latest was 2024.
Background: reading the West Nile counts; how the dates are worked out.