Mosquito season in Idaho County, ID: when it starts and ends
Mosquito months in Idaho County
In a normal year mosquito season in Idaho County, ID starts around May 24 and ends around September 7, about 15 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Idaho County, and when
- Start tipping out standing water weekly by May 10.
- Book any yard treatment for late May, ahead of the July peak.
- Repellent can go away after September 7.
- No West Nile cases since 2016, so bites in Idaho County are a nuisance; check window screens.
Idaho County against the rest of ID
Idaho County has the 40th longest season of 44 ID counties, at 106 days against 194 in Canyon County and 85 in Fremont County. Its mean temperature is 42.1°F.
- Caribou County: May 27 to September 12 (108 days, 0 WNV)
- Custer County: June 2 to September 18 (107 days, 0 WNV)
- Blaine County: June 7 to September 21 (106 days, 0 WNV)
- Adams County: June 1 to September 9 (100 days, 2 WNV)
West Nile in Idaho County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Idaho County (0 neuroinvasive) across 1 year. The worst was 2006 with 3; the latest was 2006.
More: how the dates are worked out · when mosquitoes go away for the winter.