Mosquito season in Frio County, TX: when it starts and ends
Mosquito months in Frio County
In a normal year mosquito season in Frio County, TX starts around January 26 and ends around December 23, about 47 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Frio County, and when
- Start tipping out standing water weekly by January 12.
- Book any yard treatment for late January, ahead of the August peak.
- Repellent can go away after December 23.
- No West Nile cases since 2016, so bites in Frio County are a nuisance; check window screens.
Frio County against the rest of TX
Frio County has the 30th longest season of 254 TX counties, at 331 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 71.6°F.
- Karnes County: January 28 to December 27 (333 days, 1 WNV)
- Bee County: January 29 to December 27 (332 days, 1 WNV)
- Lavaca County: January 30 to December 27 (331 days, 0 WNV)
- McMullen County: January 21 to December 17 (330 days, 0 WNV)
West Nile in Frio County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Frio County (1 neuroinvasive) across 2 years. The worst was 2012 with 2; the latest was 2012.
Background: where mosquitoes never stop; how the dates are worked out.