Mosquito season in LaPorte County, IN: when it starts and ends

Mosquito months in LaPorte County

In a normal year mosquito season in LaPorte County, IN starts around April 17 and ends around October 22, about 27 weeks.

1. Jan
2. Feb
3. Mar
4. Apr
5. May
6. Jun
7. Jul
8. Aug
9. Sep
10. Oct
11. Nov
12. Dec

What to do in LaPorte County, and when

• Start tipping out standing water weekly by April 3.
• Book any yard treatment for mid April, ahead of the July peak.
• Repellent can go away after October 22.
• 2 West Nile cases since 2016 (last 2023): you should use repellent at dusk July to August, more so if over 60.

LaPorte County against the rest of IN

LaPorte County has the 79th longest season of 92 IN counties, at 188 days against 231 in Floyd County and 177 in Steuben County. Its mean temperature is 50.1°F.

• Fulton County: April 17 to October 22 (189 days, 0 WNV)
• Kosciusko County: April 17 to October 22 (188 days, 3 WNV)
• Pulaski County: April 17 to October 22 (188 days, 0 WNV)
• Starke County: April 17 to October 21 (187 days, 0 WNV)

West Nile in LaPorte County

From 1999 to 2025, CDC ArboNET counted 11 human West Nile cases in LaPorte County (5 neuroinvasive) across 7 years. The worst was 2006 with 4; the latest was 2023.

More: how the dates are worked out · when mosquitoes go away for the winter.