Mosquito season in Adams County, ID: when it starts and ends
Mosquito months in Adams County
In a normal year mosquito season in Adams County, ID starts around June 1 and ends around September 9, about 14 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Adams County, and when
- Start tipping out standing water weekly by May 18.
- Book any yard treatment for early June, ahead of the July peak.
- Repellent can go away after September 9.
- 2 West Nile cases since 2016 (last 2021): you should use repellent at dusk July, more so if over 60.
Adams County against the rest of ID
Adams County has the 42nd longest season of 44 ID counties, at 100 days against 194 in Canyon County and 85 in Fremont County. Its mean temperature is 41.4°F.
- Idaho County: May 24 to September 7 (106 days, 0 WNV)
- Blaine County: June 7 to September 21 (106 days, 0 WNV)
- Lemhi County: June 10 to September 4 (86 days, 2 WNV)
- Fremont County: June 9 to September 2 (85 days, 0 WNV)
West Nile in Adams County
From 1999 to 2025, CDC ArboNET counted 17 human West Nile cases in Adams County (2 neuroinvasive) across 6 years. The worst was 2006 with 9; the latest was 2021.
More: how the dates are worked out · when the season starts across the US.