Mosquito season in Cedar County, IA: when it starts and ends
Mosquito months in Cedar County
In a normal year mosquito season in Cedar County, IA starts around April 16 and ends around October 20, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Cedar County, and when
- Start tipping out standing water weekly by April 2.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 20.
- 2 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.
Cedar County against the rest of IA
Cedar County has the 23rd longest season of 99 IA counties, at 187 days against 198 in Des Moines County and 160 in Worth County. Its mean temperature is 49.3°F.
- Pottawattamie County: April 16 to October 21 (188 days, 18 WNV)
- Wayne County: April 16 to October 20 (188 days, 2 WNV)
- Ringgold County: April 16 to October 20 (187 days, 0 WNV)
- Appanoose County: April 17 to October 21 (187 days, 1 WNV)
West Nile in Cedar County
From 1999 to 2025, CDC ArboNET counted 5 human West Nile cases in Cedar County (3 neuroinvasive) across 4 years. The worst was 2025 with 2; the latest was 2025.
Background: when the season starts across the US; how the dates are worked out.