Mosquito season in Oakland County, MI: when it starts and ends
Mosquito months in Oakland County
In a normal year mosquito season in Oakland County, MI starts around April 24 and ends around October 17, about 25 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Oakland County, and when
- Start tipping out standing water weekly by April 10.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 17.
- 62 West Nile cases since 2016: you should wear EPA-registered repellent at dusk July to August, and check MI spray notices.
Oakland County against the rest of MI
Oakland County has the 15th longest season of 83 MI counties, at 176 days against 189 in Allegan County and 124 in Iron County. Its mean temperature is 48.2°F.
- Cass County: April 24 to October 20 (179 days, 2 WNV)
- Branch County: April 23 to October 16 (176 days, 0 WNV)
- Macomb County: April 26 to October 19 (176 days, 50 WNV)
- Hillsdale County: April 24 to October 16 (175 days, 2 WNV)
West Nile in Oakland County
From 1999 to 2025, CDC ArboNET counted 323 human West Nile cases in Oakland County (274 neuroinvasive) across 21 years. The worst was 2002 with 208; the latest was 2025.
More: how the dates are worked out · reading the West Nile counts.