Mosquito season in McLennan County, TX: when it starts and ends
Mosquito months in McLennan County
In a normal year mosquito season in McLennan County, TX starts around February 25 and ends around December 3, about 40 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in McLennan County, and when
- Start tipping out standing water weekly by February 11.
- Book any yard treatment for late February, ahead of the August peak.
- Repellent can go away after December 3.
- 17 West Nile cases since 2016: you should wear EPA-registered repellent at dusk May to September, and check TX spray notices.
McLennan County against the rest of TX
McLennan County has the 84th longest season of 254 TX counties, at 281 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 66.7°F.
- Panola County: February 24 to December 2 (281 days, 1 WNV)
- Colorado County: February 25 to December 3 (281 days, 2 WNV)
- Morris County: February 24 to December 1 (280 days, 0 WNV)
- Bastrop County: February 26 to December 3 (280 days, 5 WNV)
West Nile in McLennan County
From 1999 to 2025, CDC ArboNET counted 72 human West Nile cases in McLennan County (54 neuroinvasive) across 9 years. The worst was 2012 with 44; the latest was 2024.
Background: reading the West Nile counts; how the dates are worked out.