Mosquito season in Kalamazoo County, MI: when it starts and ends
Mosquito months in Kalamazoo County
In a normal year mosquito season in Kalamazoo County, MI starts around April 19 and ends around October 19, about 26 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Kalamazoo County, and when
- Start tipping out standing water weekly by April 5.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 19.
- 6 West Nile cases since 2016 (last 2025): you should use repellent at dusk July to August, more so if over 60.
Kalamazoo County against the rest of MI
Kalamazoo County has the 5th longest season of 83 MI counties, at 183 days against 189 in Allegan County and 124 in Iron County. Its mean temperature is 49.5°F.
- Van Buren County: April 22 to October 26 (187 days, 1 WNV)
- Monroe County: April 21 to October 22 (184 days, 7 WNV)
- Wayne County: April 21 to October 21 (183 days, 110 WNV)
- Lenawee County: April 20 to October 19 (182 days, 3 WNV)
West Nile in Kalamazoo County
From 1999 to 2025, CDC ArboNET counted 12 human West Nile cases in Kalamazoo County (11 neuroinvasive) across 8 years. The worst was 2025 with 3; the latest was 2025.
See how the dates are worked out, and reading the West Nile counts.