Mosquito season in Dubuque County, IA: when it starts and ends
Mosquito months in Dubuque County
In a normal year mosquito season in Dubuque County, IA starts around April 21 and ends around October 15, about 25 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Dubuque County, and when
- Start tipping out standing water weekly by April 7.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 15.
- 2 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to August, more so if over 60.
Dubuque County against the rest of IA
Dubuque County has the 55th longest season of 99 IA counties, at 177 days against 198 in Des Moines County and 160 in Worth County. Its mean temperature is 47.5°F.
- Palo Alto County: April 21 to October 16 (178 days, 1 WNV)
- Tama County: April 21 to October 16 (178 days, 3 WNV)
- Ida County: April 21 to October 15 (177 days, 3 WNV)
- Calhoun County: April 22 to October 16 (177 days, 2 WNV)
West Nile in Dubuque County
From 1999 to 2025, CDC ArboNET counted 4 human West Nile cases in Dubuque County (2 neuroinvasive) across 4 years. The worst was 2025 with 1; the latest was 2025.
Background: when the season starts across the US; how the dates are worked out.