Mosquito season in Mississippi County, MO: when it starts and ends
Mosquito months in Mississippi County
In a normal year mosquito season in Mississippi County, MO starts around March 24 and ends around November 9, about 33 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Mississippi County, and when
- Start tipping out standing water weekly by March 10.
- Book any yard treatment for late March, ahead of the July peak.
- Repellent can go away after November 9.
- No West Nile cases since 2016, so bites in Mississippi County are a nuisance; check window screens.
Mississippi County against the rest of MO
Mississippi County has the 6th longest season of 115 MO counties, at 230 days against 242 in Pemiscot County and 187 in Crawford County. Its mean temperature is 58.6°F.
- Butler County: March 20 to November 9 (234 days, 3 WNV)
- Scott County: March 21 to November 8 (232 days, 0 WNV)
- St. Louis city: March 24 to November 8 (229 days, 39 WNV)
- Taney County: March 26 to November 9 (228 days, 0 WNV)
West Nile in Mississippi County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Mississippi County (0 neuroinvasive) across 1 year. The worst was 2002 with 1; the latest was 2002.
Background: when the season starts across the US; how the dates are worked out.