Mosquito season in Boone County, MO: when it starts and ends
Mosquito months in Boone County
In a normal year mosquito season in Boone County, MO starts around March 27 and ends around November 4, about 32 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Boone County, and when
- Start tipping out standing water weekly by March 13.
- Book any yard treatment for late March, ahead of the July peak.
- Repellent can go away after November 4.
- 5 West Nile cases since 2016 (last 2024): you should use repellent at dusk June to August, more so if over 60.
Boone County against the rest of MO
Boone County has the 19th longest season of 115 MO counties, at 221 days against 242 in Pemiscot County and 187 in Crawford County. Its mean temperature is 56.1°F.
- Maries County: March 28 to November 5 (222 days, 0 WNV)
- Hickory County: March 29 to November 6 (222 days, 0 WNV)
- Phelps County: March 28 to November 4 (220 days, 1 WNV)
- Reynolds County: March 28 to November 3 (220 days, 0 WNV)
West Nile in Boone County
From 1999 to 2025, CDC ArboNET counted 24 human West Nile cases in Boone County (14 neuroinvasive) across 12 years. The worst was 2007 with 9; the latest was 2024.
More: how the dates are worked out · reading the West Nile counts.