Mosquito season in Seward County, KS: when it starts and ends
Mosquito months in Seward County
In a normal year mosquito season in Seward County, KS starts around April 9 and ends around November 1, about 29 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Seward County, and when
- Start tipping out standing water weekly by March 26.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after November 1.
- 2 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to September, more so if over 60.
Seward County against the rest of KS
Seward County has the 43rd longest season of 105 KS counties, at 206 days against 227 in Cherokee County and 178 in Thomas County. Its mean temperature is 56.5°F.
- Jefferson County: April 7 to October 30 (206 days, 1 WNV)
- Stafford County: April 7 to October 30 (206 days, 4 WNV)
- Kearny County: April 7 to October 29 (205 days, 2 WNV)
- Franklin County: April 8 to October 30 (205 days, 1 WNV)
West Nile in Seward County
From 1999 to 2025, CDC ArboNET counted 7 human West Nile cases in Seward County (4 neuroinvasive) across 4 years. The worst was 2003 with 4; the latest was 2025.
See how the dates are worked out, and when mosquitoes go away for the winter.