Mosquito season in Republic County, KS: when it starts and ends

Mosquito months in Republic County

In a normal year mosquito season in Republic County, KS starts around April 12 and ends around October 25, about 28 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 Republic County, and when

• Start tipping out standing water weekly by March 29.
• Book any yard treatment for mid April, ahead of the July peak.
• Repellent can go away after October 25.
• 4 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.

Republic County against the rest of KS

Republic County has the 72nd longest season of 105 KS counties, at 196 days against 227 in Cherokee County and 178 in Thomas County. Its mean temperature is 52.7°F.

• Sheridan County: April 10 to October 25 (199 days, 0 WNV)
• Russell County: April 12 to October 27 (198 days, 0 WNV)
• Ellsworth County: April 13 to October 26 (196 days, 1 WNV)
• Trego County: April 13 to October 26 (196 days, 1 WNV)

West Nile in Republic County

From 1999 to 2025, CDC ArboNET counted 9 human West Nile cases in Republic County (4 neuroinvasive) across 7 years. The worst was 2013 with 3; the latest was 2025.

See how the dates are worked out, and reading the West Nile counts.