Mosquito season in Naugatuck Valley Planning Region, CT: when it starts and ends

Mosquito months in Naugatuck Valley Planning Region

In a normal year mosquito season in Naugatuck Valley Planning Region, CT starts around April 20 and ends around October 23, about 27 weeks.

What to do in Naugatuck Valley Planning Region, and when

Start tipping out standing water weekly by April 6.
Book any yard treatment for mid April, ahead of the July peak.
Repellent can go away after October 23.
No West Nile cases since 2016, so bites in Naugatuck Valley Planning Region are a nuisance; check window screens.

Naugatuck Valley Planning Region against the rest of CT

Naugatuck Valley Planning Region has the 6th longest season of 9 CT counties, at 187 days against 200 in Greater Bridgeport Planning Region and 164 in Northwest Hills Planning Region. Its mean temperature is 50.6°F.

South Central Connecticut Planning Region: April 19 to October 29 (192 days, 5 WNV)
Lower Connecticut River Valley Planning Region: April 17 to October 25 (191 days, 1 WNV)
Western Connecticut Planning Region: April 19 to October 22 (186 days, 10 WNV)
Northeastern Connecticut Planning Region: April 25 to October 17 (175 days, 0 WNV)

West Nile in Naugatuck Valley Planning Region

CDC ArboNET lists no human West Nile cases for Naugatuck Valley Planning Region from 1999 to 2025, though virus turned up in birds, mosquitoes or horses in 2 of those years.

More: how the dates are worked out · when mosquitoes go away for the winter.