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

Mosquito months in Orange County

In a normal year mosquito season in Orange County, TX starts around February 3 and ends around December 12, 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 Orange County, and when

• Start tipping out standing water weekly by January 20.
• Book any yard treatment for early February, ahead of the August peak.
• Repellent can go away after December 12.
• 4 West Nile cases since 2016 (last 2020): you should use repellent at dusk May to October, more so if over 60.

Orange County against the rest of TX

Orange County has the 53rd longest season of 254 TX counties, at 312 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 68.6°F.

• Austin County: February 10 to December 20 (313 days, 0 WNV)
• Travis County: February 27 to January 6 (313 days, 56 WNV)
• Walker County: February 8 to December 16 (311 days, 4 WNV)
• Washington County: February 10 to December 18 (311 days, 0 WNV)

West Nile in Orange County

From 1999 to 2025, CDC ArboNET counted 32 human West Nile cases in Orange County (23 neuroinvasive) across 11 years. The worst was 2002 with 8; the latest was 2020.

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