Mosquito season in Butler County, NE: when it starts and ends
Mosquito months in Butler County
In a normal year mosquito season in Butler County, NE starts around April 18 and ends around October 18, about 26 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Butler County, and when
- Start tipping out standing water weekly by April 4.
- Book any yard treatment for mid April, ahead of the July peak.
- Repellent can go away after October 18.
- 11 West Nile cases since 2016: you should wear EPA-registered repellent at dusk June to August, and check NE spray notices.
Butler County against the rest of NE
Butler County has the 34th longest season of 93 NE counties, at 183 days against 200 in Richardson County and 127 in Sioux County. Its mean temperature is 49.2°F.
- Burt County: April 18 to October 19 (184 days, 1 WNV)
- Dawson County: April 18 to October 18 (184 days, 14 WNV)
- Gosper County: April 18 to October 19 (183 days, 0 WNV)
- Dundy County: April 19 to October 19 (183 days, 1 WNV)
West Nile in Butler County
From 1999 to 2025, CDC ArboNET counted 34 human West Nile cases in Butler County (13 neuroinvasive) across 14 years. The worst was 2003 with 11; the latest was 2025.
See how the dates are worked out, and reading the West Nile counts.