Mosquito season in Hamilton County, TX: when it starts and ends
Mosquito months in Hamilton County
In a normal year mosquito season in Hamilton County, TX starts around March 2 and ends around November 30, about 39 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Hamilton County, and when
- Start tipping out standing water weekly by February 16.
- Book any yard treatment for early March, ahead of the August peak.
- Repellent can go away after November 30.
- 1 West Nile case since 2016 (last 2016): you should use repellent at dusk May to September, more so if over 60.
Hamilton County against the rest of TX
Hamilton County has the 104th longest season of 254 TX counties, at 273 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 65.3°F.
- Shelby County: February 28 to November 28 (273 days, 1 WNV)
- Rusk County: March 1 to November 29 (273 days, 3 WNV)
- Bandera County: March 2 to November 29 (272 days, 0 WNV)
- Uvalde County: March 1 to November 27 (271 days, 1 WNV)
West Nile in Hamilton County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Hamilton County (0 neuroinvasive) across 1 year. The worst was 2016 with 1; the latest was 2016.
More: how the dates are worked out · when mosquitoes go away for the winter.