Mosquito season in Bexar County, TX: when it starts and ends

Mosquito months in Bexar County

In a normal year mosquito season in Bexar County, TX starts around February 5 and ends around December 15, about 45 weeks.

1. Jan
2. Feb
3. Mar
4. Apr
5. May
6. Jun
7. Jul
8. Aug
9. Sep
10. Oct
11. Nov
12. Dec

What to do in Bexar County, and when

• Start tipping out standing water weekly by January 22.
• Book any yard treatment for early February, ahead of the August peak.
• Repellent can go away after December 15.
• 30 West Nile cases since 2016: you should wear EPA-registered repellent at dusk May to October, and check TX spray notices.

Bexar County against the rest of TX

Bexar County has the 49th longest season of 254 TX counties, at 313 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 69.3°F.

• Brazos County: February 7 to December 18 (314 days, 8 WNV)
• Refugio County: February 7 to December 18 (314 days, 0 WNV)
• Goliad County: February 5 to December 15 (313 days, 0 WNV)
• Austin County: February 10 to December 20 (313 days, 0 WNV)

West Nile in Bexar County

From 1999 to 2025, CDC ArboNET counted 105 human West Nile cases in Bexar County (75 neuroinvasive) across 16 years. The worst was 2012 with 31; the latest was 2025.

See how the dates are worked out, and reading the West Nile counts.