Mosquito season in Osborne County, KS: when it starts and ends
Mosquito months in Osborne County
In a normal year mosquito season in Osborne County, KS starts around April 19 and ends around October 22, about 27 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Osborne 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 22.
- 1 West Nile case since 2016 (last 2017): you should use repellent at dusk June to August, more so if over 60.
Osborne County against the rest of KS
Osborne County has the 91st longest season of 105 KS counties, at 186 days against 227 in Cherokee County and 178 in Thomas County. Its mean temperature is 53°F.
- Ness County: April 18 to October 22 (187 days, 7 WNV)
- Graham County: April 19 to October 22 (186 days, 2 WNV)
- Jewell County: April 20 to October 23 (186 days, 0 WNV)
- Scott County: April 20 to October 23 (186 days, 4 WNV)
West Nile in Osborne County
From 1999 to 2025, CDC ArboNET counted 5 human West Nile cases in Osborne County (4 neuroinvasive) across 4 years. The worst was 2003 with 2; the latest was 2017.
Background: when mosquitoes go away for the winter; how the dates are worked out.