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

Mosquito months in DeWitt County

In a normal year mosquito season in DeWitt County, TX starts around February 15 and ends around December 9, about 42 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 DeWitt County, and when

• Start tipping out standing water weekly by February 1.
• Book any yard treatment for mid February, ahead of the August peak.
• Repellent can go away after December 9.
• No West Nile cases since 2016, so bites in DeWitt County are a nuisance; check window screens.

DeWitt County against the rest of TX

DeWitt County has the 65th longest season of 254 TX counties, at 297 days against 365 in Cameron County and 191 in Lipscomb County. Its mean temperature is 70.9°F.

• Medina County: February 12 to December 9 (300 days, 1 WNV)
• Fayette County: February 15 to December 10 (298 days, 0 WNV)
• Dallas County: February 18 to December 12 (297 days, 219 WNV)
• Kinney County: February 16 to December 6 (293 days, 0 WNV)

West Nile in DeWitt County

From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in DeWitt County (1 neuroinvasive) across 2 years. The worst was 2012 with 2; the latest was 2012.

See how the dates are worked out, and when the season starts across the US.