Mosquito season in Brown County, KS: when it starts and ends
Mosquito months in Brown County
In a normal year mosquito season in Brown County, KS starts around April 8 and ends around October 26, about 29 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Brown County, and when
- Start tipping out standing water weekly by March 25.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 26.
- 1 West Nile case since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.
Brown County against the rest of KS
Brown County has the 62nd longest season of 105 KS counties, at 201 days against 227 in Cherokee County and 178 in Thomas County. Its mean temperature is 52.5°F.
- Kiowa County: April 11 to October 30 (202 days, 0 WNV)
- Pawnee County: April 12 to October 31 (202 days, 1 WNV)
- Leavenworth County: April 9 to October 27 (201 days, 2 WNV)
- Reno County: April 10 to October 28 (201 days, 11 WNV)
West Nile in Brown County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Brown County (1 neuroinvasive) across 1 year. The worst was 2025 with 1; the latest was 2025.
Background: when mosquitoes go away for the winter; how the dates are worked out.