Mosquito season in Chase County, NE: when it starts and ends
Mosquito months in Chase County
In a normal year mosquito season in Chase County, NE starts around April 29 and ends around October 13, about 24 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Chase County, and when
- Start tipping out standing water weekly by April 15.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 13.
- 7 West Nile cases since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.
Chase County against the rest of NE
Chase County has the 80th longest season of 93 NE counties, at 167 days against 200 in Richardson County and 127 in Sioux County. Its mean temperature is 50.4°F.
- McPherson County: April 28 to October 12 (167 days, 0 WNV)
- Scotts Bluff County: April 28 to October 12 (167 days, 50 WNV)
- Morrill County: April 29 to October 13 (167 days, 12 WNV)
- Arthur County: April 30 to October 12 (165 days, 0 WNV)
West Nile in Chase County
From 1999 to 2025, CDC ArboNET counted 45 human West Nile cases in Chase County (4 neuroinvasive) across 10 years. The worst was 2003 with 30; the latest was 2025.
More: how the dates are worked out · reading the West Nile counts.