Mosquito season in Grant County, IN: when it starts and ends
Mosquito months in Grant County
In a normal year mosquito season in Grant County, IN starts around April 16 and ends around October 23, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Grant County, and when
- Start tipping out standing water weekly by April 2.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 23.
- 2 West Nile cases since 2016 (last 2018): you should use repellent at dusk June to August, more so if over 60.
Grant County against the rest of IN
Grant County has the 72nd longest season of 92 IN counties, at 190 days against 231 in Floyd County and 177 in Steuben County. Its mean temperature is 50.5°F.
- Adams County: April 16 to October 23 (190 days, 0 WNV)
- Allen County: April 16 to October 23 (190 days, 11 WNV)
- Jasper County: April 16 to October 22 (189 days, 2 WNV)
- Jay County: April 16 to October 22 (189 days, 2 WNV)
West Nile in Grant County
From 1999 to 2025, CDC ArboNET counted 11 human West Nile cases in Grant County (6 neuroinvasive) across 4 years. The worst was 2002 with 6; the latest was 2018.
See how the dates are worked out, and when the season starts across the US.