Mosquito season in King County, TX: when it starts and ends
Mosquito months in King County
In a normal year mosquito season in King County, TX starts around March 19 and ends around November 12, about 34 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in King County, and when
- Start tipping out standing water weekly by March 5.
- Book any yard treatment for mid March, ahead of the July peak.
- Repellent can go away after November 12.
- No West Nile cases since 2016, so bites in King County are a nuisance; check window screens.
King County against the rest of TX
King County has the 212th longest season of 254 TX counties, at 238 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 63°F.
- Irion County: March 19 to November 12 (238 days, 2 WNV)
- Kerr County: March 19 to November 12 (238 days, 0 WNV)
- Concho County: March 20 to November 13 (238 days, 0 WNV)
- Glasscock County: March 21 to November 14 (238 days, 1 WNV)
West Nile in King County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in King County (1 neuroinvasive) across 1 year. The worst was 2006 with 1; the latest was 2006.
Background: when the season starts across the US; how the dates are worked out.