Mosquito season in Kitsap County, WA: when it starts and ends
Mosquito months in Kitsap County
In a normal year mosquito season in Kitsap County, WA starts around April 15 and ends around October 25, about 28 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Kitsap County, and when
- Start tipping out standing water weekly by April 1.
- Book any yard treatment for mid April, ahead of the August peak.
- Repellent can go away after October 25.
- No West Nile cases since 2016, so bites in Kitsap County are a nuisance; check window screens.
Kitsap County against the rest of WA
Kitsap County has the 4th longest season of 39 WA counties, at 193 days against 205 in Walla Walla County and 132 in Asotin County. Its mean temperature is 52.2°F.
- Benton County: April 5 to October 22 (200 days, 10 WNV)
- Cowlitz County: April 11 to October 28 (200 days, 0 WNV)
- Franklin County: April 10 to October 18 (191 days, 1 WNV)
- Yakima County: April 12 to October 17 (188 days, 4 WNV)
West Nile in Kitsap County
CDC ArboNET lists no human West Nile cases for Kitsap County from 1999 to 2025.
More: how the dates are worked out · when mosquitoes go away for the winter.