Mosquito season in Caribou County, ID: when it starts and ends
Mosquito months in Caribou County
In a normal year mosquito season in Caribou County, ID starts around May 27 and ends around September 12, about 15 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Caribou County, and when
- Start tipping out standing water weekly by May 13.
- Book any yard treatment for late May, ahead of the July peak.
- Repellent can go away after September 12.
- No West Nile cases since 2016, so bites in Caribou County are a nuisance; check window screens.
Caribou County against the rest of ID
Caribou County has the 38th longest season of 44 ID counties, at 108 days against 194 in Canyon County and 85 in Fremont County. Its mean temperature is 42.1°F.
- Camas County: May 28 to September 19 (114 days, 0 WNV)
- Elmore County: May 30 to September 18 (111 days, 4 WNV)
- Custer County: June 2 to September 18 (107 days, 0 WNV)
- Idaho County: May 24 to September 7 (106 days, 0 WNV)
West Nile in Caribou County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Caribou County (1 neuroinvasive) across 1 year. The worst was 2011 with 1; the latest was 2011.
See how the dates are worked out, and when mosquitoes go away for the winter.