Mosquito season in Iron County, MI: when it starts and ends
Mosquito months in Iron County
In a normal year mosquito season in Iron County, MI starts around May 24 and ends around September 25, about 18 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Iron County, and when
- Start tipping out standing water weekly by May 10.
- Book any yard treatment for late May, ahead of the July peak.
- Repellent can go away after September 25.
- No West Nile cases since 2016, so bites in Iron County are a nuisance; check window screens.
Iron County against the rest of MI
Iron County has the 83rd longest season of 83 MI counties, at 124 days against 189 in Allegan County and 124 in Iron County. Its mean temperature is 38.9°F.
- Baraga County: May 14 to September 29 (138 days, 0 WNV)
- Houghton County: May 17 to September 30 (137 days, 0 WNV)
West Nile in Iron County
CDC ArboNET lists no human West Nile cases for Iron County from 1999 to 2025, though virus turned up in birds, mosquitoes or horses in 9 of those years.
See how the dates are worked out, and when mosquitoes go away for the winter.