Mosquito season in Keokuk County, IA: when it starts and ends
Mosquito months in Keokuk County
In a normal year mosquito season in Keokuk County, IA starts around April 18 and ends around October 19, about 26 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Keokuk County, and when
- Start tipping out standing water weekly by April 4.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 19.
- 1 West Nile case since 2016 (last 2024): you should use repellent at dusk July to August, more so if over 60.
Keokuk County against the rest of IA
Keokuk County has the 35th longest season of 99 IA counties, at 184 days against 198 in Des Moines County and 160 in Worth County. Its mean temperature is 49°F.
- Adams County: April 18 to October 19 (185 days, 2 WNV)
- Clarke County: April 18 to October 20 (185 days, 1 WNV)
- Union County: April 18 to October 19 (184 days, 0 WNV)
- Black Hawk County: April 18 to October 18 (183 days, 0 WNV)
West Nile in Keokuk County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Keokuk County (2 neuroinvasive) across 2 years. The worst was 2003 with 2; the latest was 2024.
Background: when mosquitoes go away for the winter; how the dates are worked out.