Mosquito season in Washington County, FL: when it starts and ends

Mosquito months in Washington County

In a normal year mosquito season in Washington County, FL starts around February 16 and ends around December 8, 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 Washington County, and when

• Start tipping out standing water weekly by February 2.
• Book any yard treatment for mid February, ahead of the July peak.
• Repellent can go away after December 8.
• 1 West Nile case since 2016 (last 2018): you should use repellent at dusk May to September, more so if over 60.

Washington County against the rest of FL

Washington County has the 61st longest season of 67 FL counties, at 295 days against 365 in Broward County and 281 in Gilchrist County. Its mean temperature is 67.7°F.

• Taylor County: February 16 to December 14 (301 days, 2 WNV)
• Lafayette County: February 17 to December 13 (299 days, 1 WNV)
• Hamilton County: February 22 to December 7 (288 days, 0 WNV)
• Wakulla County: February 26 to December 11 (288 days, 1 WNV)

West Nile in Washington County

From 1999 to 2025, CDC ArboNET counted 5 human West Nile cases in Washington County (5 neuroinvasive) across 4 years. The worst was 2003 with 2; the latest was 2018.

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