Mosquito season in Arenac County, MI: when it starts and ends
Mosquito months in Arenac County
In a normal year mosquito season in Arenac County, MI starts around May 3 and ends around October 11, about 23 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Arenac County, and when
- Start tipping out standing water weekly by April 19.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 11.
- No West Nile cases since 2016, so bites in Arenac County are a nuisance; check window screens.
Arenac County against the rest of MI
Arenac County has the 46th longest season of 83 MI counties, at 161 days against 189 in Allegan County and 124 in Iron County. Its mean temperature is 45.5°F.
- Gladwin County: May 2 to October 10 (162 days, 0 WNV)
- Mecosta County: May 1 to October 9 (161 days, 0 WNV)
- Leelanau County: May 6 to October 13 (161 days, 1 WNV)
- Oscoda County: May 5 to October 9 (157 days, 1 WNV)
West Nile in Arenac County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Arenac County (1 neuroinvasive) across 1 year. The worst was 2002 with 1; the latest was 2002.
Background: when mosquitoes go away for the winter; how the dates are worked out.