Mosquito season in Barry County, MI: when it starts and ends
Mosquito months in Barry County
In a normal year mosquito season in Barry County, MI starts around April 25 and ends around October 16, about 25 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Barry County, and when
- Start tipping out standing water weekly by April 11.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 16.
- 2 West Nile cases since 2016 (last 2020): you should use repellent at dusk July to July, more so if over 60.
Barry County against the rest of MI
Barry County has the 18th longest season of 83 MI counties, at 174 days against 189 in Allegan County and 124 in Iron County. Its mean temperature is 47.9°F.
- Macomb County: April 26 to October 19 (176 days, 50 WNV)
- Hillsdale County: April 24 to October 16 (175 days, 2 WNV)
- Saginaw County: April 25 to October 17 (174 days, 1 WNV)
- St. Clair County: April 26 to October 17 (174 days, 6 WNV)
West Nile in Barry County
From 1999 to 2025, CDC ArboNET counted 6 human West Nile cases in Barry County (4 neuroinvasive) across 6 years. The worst was 2020 with 1; the latest was 2020.
See how the dates are worked out, and when mosquitoes go away for the winter.