Mosquito season in Kootenai County, ID: when it starts and ends
Mosquito months in Kootenai County
In a normal year mosquito season in Kootenai County, ID starts around May 1 and ends around October 8, about 23 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Kootenai County, and when
- Start tipping out standing water weekly by April 17.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 8.
- 2 West Nile cases since 2016 (last 2023): you should use repellent at dusk July, more so if over 60.
Kootenai County against the rest of ID
Kootenai County has the 15th longest season of 44 ID counties, at 160 days against 194 in Canyon County and 85 in Fremont County. Its mean temperature is 47.6°F.
- Minidoka County: May 2 to October 11 (162 days, 0 WNV)
- Cassia County: May 3 to October 11 (161 days, 1 WNV)
- Benewah County: May 3 to October 7 (157 days, 0 WNV)
- Boundary County: April 30 to October 1 (154 days, 0 WNV)
West Nile in Kootenai County
From 1999 to 2025, CDC ArboNET counted 4 human West Nile cases in Kootenai County (3 neuroinvasive) across 4 years. The worst was 2023 with 1; the latest was 2023.
See how the dates are worked out, and when the season starts across the US.