Mosquito season in Holt County, MO: when it starts and ends
Mosquito months in Holt County
In a normal year mosquito season in Holt County, MO starts around April 8 and ends around October 25, about 29 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Holt County, and when
- Start tipping out standing water weekly by March 25.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 25.
- No West Nile cases since 2016, so bites in Holt County are a nuisance; check window screens.
Holt County against the rest of MO
Holt County has the 90th longest season of 115 MO counties, at 200 days against 242 in Pemiscot County and 187 in Crawford County. Its mean temperature is 52.5°F.
- Livingston County: April 8 to October 26 (201 days, 1 WNV)
- Ray County: April 8 to October 26 (201 days, 0 WNV)
- Buchanan County: April 9 to October 26 (200 days, 7 WNV)
- Grundy County: April 9 to October 26 (200 days, 1 WNV)
West Nile in Holt County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Holt County (1 neuroinvasive) across 2 years. The worst was 2007 with 1; the latest was 2007.
Background: when the season starts across the US; how the dates are worked out.