Mosquito season in Atchison County, KS: when it starts and ends
Mosquito months in Atchison County
In a normal year mosquito season in Atchison County, KS starts around April 4 and ends around October 29, about 30 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Atchison County, and when
- Start tipping out standing water weekly by March 21.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 29.
- 2 West Nile cases since 2016 (last 2024): you should use repellent at dusk June to August, more so if over 60.
Atchison County against the rest of KS
Atchison County has the 37th longest season of 105 KS counties, at 207 days against 227 in Cherokee County and 178 in Thomas County. Its mean temperature is 54°F.
- Greenwood County: April 5 to October 30 (208 days, 0 WNV)
- Rice County: April 6 to October 31 (208 days, 2 WNV)
- Lyon County: April 5 to October 29 (207 days, 0 WNV)
- Saline County: April 7 to October 31 (207 days, 9 WNV)
West Nile in Atchison County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Atchison County (2 neuroinvasive) across 3 years. The worst was 2024 with 1; the latest was 2024.
See how the dates are worked out, and when the season starts across the US.