Mosquito season in Dallas County, AR: when it starts and ends

Mosquito months in Dallas County

In a normal year mosquito season in Dallas County, AR starts around March 10 and ends around November 17, about 36 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 Dallas County, and when

• Start tipping out standing water weekly by February 24.
• Book any yard treatment for early March, ahead of the July peak.
• Repellent can go away after November 17.
• 3 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to September, more so if over 60.

Dallas County against the rest of AR

Dallas County has the 30th longest season of 75 AR counties, at 252 days against 274 in Chicot County and 211 in Washington County. Its mean temperature is 61.9°F.

• Little River County: March 11 to November 21 (255 days, 1 WNV)
• Saline County: March 9 to November 18 (254 days, 6 WNV)
• Mississippi County: March 11 to November 18 (252 days, 2 WNV)
• Hempstead County: March 11 to November 17 (251 days, 0 WNV)

West Nile in Dallas County

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

Background: when mosquitoes go away for the winter; how the dates are worked out.