Mosquito season in Webster County, MO: when it starts and ends
Mosquito months in Webster County
In a normal year mosquito season in Webster County, MO starts around April 1 and ends around November 2, about 31 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Webster County, and when
- Start tipping out standing water weekly by March 18.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after November 2.
- 1 West Nile case since 2016 (last 2023): you should use repellent at dusk June to August, more so if over 60.
Webster County against the rest of MO
Webster County has the 44th longest season of 115 MO counties, at 215 days against 242 in Pemiscot County and 187 in Crawford County. Its mean temperature is 55.5°F.
- Osage County: March 31 to November 1 (215 days, 0 WNV)
- Washington County: March 31 to November 1 (215 days, 0 WNV)
- Bollinger County: April 1 to November 1 (214 days, 0 WNV)
- Moniteau County: April 1 to November 1 (214 days, 0 WNV)
West Nile in Webster County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Webster County (2 neuroinvasive) across 2 years. The worst was 2023 with 1; the latest was 2023.
Background: when mosquitoes go away for the winter; how the dates are worked out.