Mosquito season in Clearwater County, ID: when it starts and ends
Mosquito months in Clearwater County
In a normal year mosquito season in Clearwater County, ID starts around May 18 and ends around September 20, about 18 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Clearwater County, and when
- Start tipping out standing water weekly by May 4.
- Book any yard treatment for mid May, ahead of the July peak.
- Repellent can go away after September 20.
- No West Nile cases since 2016, so bites in Clearwater County are a nuisance; check window screens.
Clearwater County against the rest of ID
Clearwater County has the 32nd longest season of 44 ID counties, at 125 days against 194 in Canyon County and 85 in Fremont County. Its mean temperature is 43.2°F.
- Boise County: May 21 to September 27 (129 days, 0 WNV)
- Bonneville County: May 19 to September 23 (127 days, 0 WNV)
- Teton County: May 22 to September 20 (121 days, 1 WNV)
- Valley County: May 30 to September 23 (116 days, 1 WNV)
West Nile in Clearwater County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Clearwater County (0 neuroinvasive) across 1 year. The worst was 2006 with 1; the latest was 2006.
See how the dates are worked out, and when the season starts across the US.