Mosquito season in Washington Parish, LA: when it starts and ends

Mosquito months in Washington Parish

In a normal year mosquito season in Washington Parish, LA starts around February 11 and ends around January 11, about 48 weeks.

What to do in Washington Parish, and when

Start tipping out standing water weekly by January 28.
Book any yard treatment for mid February, ahead of the July peak.
Repellent can go away after January 11.
10 West Nile cases since 2016: you should wear EPA-registered repellent at dusk May to September, and check LA spray notices.

Washington Parish against the rest of LA

Washington Parish has the 15th longest season of 64 LA counties, at 334 days against 358 in Orleans Parish and 247 in Claiborne Parish. Its mean temperature is 66.8°F.

St. John the Baptist Parish: January 28 to January 1 (338 days, 2 WNV)
Beauregard Parish: February 12 to January 13 (335 days, 2 WNV)
Pointe Coupee Parish: January 31 to December 29 (332 days, 1 WNV)
Jefferson Davis Parish: January 31 to December 28 (331 days, 3 WNV)

West Nile in Washington Parish

From 1999 to 2025, CDC ArboNET counted 45 human West Nile cases in Washington Parish (29 neuroinvasive) across 17 years. The worst was 2002 with 10; the latest was 2025.

See how the dates are worked out, and where mosquitoes never stop.