Mosquito season in Buchanan County, IA: when it starts and ends
Mosquito months in Buchanan County
In a normal year mosquito season in Buchanan County, IA starts around April 22 and ends around October 15, about 25 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Buchanan County, and when
- Start tipping out standing water weekly by April 8.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 15.
- No West Nile cases since 2016, so bites in Buchanan County are a nuisance; check window screens.
Buchanan County against the rest of IA
Buchanan County has the 68th longest season of 99 IA counties, at 175 days against 198 in Des Moines County and 160 in Worth County. Its mean temperature is 46.8°F.
- Poweshiek County: April 23 to October 16 (176 days, 2 WNV)
- Audubon County: April 22 to October 14 (175 days, 2 WNV)
- Plymouth County: April 22 to October 14 (175 days, 10 WNV)
- Guthrie County: April 23 to October 15 (175 days, 1 WNV)
West Nile in Buchanan County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Buchanan County (0 neuroinvasive) across 1 year. The worst was 2014 with 1; the latest was 2014.
See how the dates are worked out, and when mosquitoes go away for the winter.