Mosquito season in Montcalm County, MI: when it starts and ends
Mosquito months in Montcalm County
In a normal year mosquito season in Montcalm County, MI starts around May 4 and ends around October 7, about 22 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Montcalm County, and when
- Start tipping out standing water weekly by April 20.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 7.
- 3 West Nile cases since 2016 (last 2017): you should use repellent at dusk July to July, more so if over 60.
Montcalm County against the rest of MI
Montcalm County has the 50th longest season of 83 MI counties, at 156 days against 189 in Allegan County and 124 in Iron County. Its mean temperature is 47°F.
- Oscoda County: May 5 to October 9 (157 days, 1 WNV)
- Iosco County: May 6 to October 10 (157 days, 0 WNV)
- Osceola County: May 5 to October 7 (156 days, 0 WNV)
- Antrim County: May 8 to October 11 (156 days, 0 WNV)
West Nile in Montcalm County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Montcalm County (2 neuroinvasive) across 1 year. The worst was 2017 with 3; the latest was 2017.
See how the dates are worked out, and when the season starts across the US.