Mosquito season in Cheyenne County, NE: when it starts and ends
Mosquito months in Cheyenne County
In a normal year mosquito season in Cheyenne County, NE starts around April 27 and ends around October 13, about 24 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Cheyenne County, and when
- Start tipping out standing water weekly by April 13.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 13.
- 11 West Nile cases since 2016: you should wear EPA-registered repellent at dusk July to August, and check NE spray notices.
Cheyenne County against the rest of NE
Cheyenne County has the 72nd longest season of 93 NE counties, at 169 days against 200 in Richardson County and 127 in Sioux County. Its mean temperature is 49.4°F.
- Logan County: April 26 to October 12 (169 days, 1 WNV)
- Brown County: April 27 to October 13 (169 days, 1 WNV)
- Rock County: April 26 to October 11 (168 days, 0 WNV)
- Garfield County: April 27 to October 12 (168 days, 1 WNV)
West Nile in Cheyenne County
From 1999 to 2025, CDC ArboNET counted 28 human West Nile cases in Cheyenne County (5 neuroinvasive) across 12 years. The worst was 2023 with 7; the latest was 2024.
Background: reading the West Nile counts; how the dates are worked out.