Light to moderate smoke is expected across much of North Idaho and the Central Mountains, with pockets of heavier smoke across portions of the Panhandle, north-central Idaho, and near active wildfires. Across South Idaho, generally light smoke and haze will affect portions of southwest Idaho and the Snake River Plain. Smoke from fires in and near the Owyhee Mountains will produce localized plumes of moderate to heavy smoke, particularly near the mountains and immediately downwind, while much of East Idaho remains comparatively less impacted.
Overnight into Thursday morning, light to moderate smoke will remain widespread across North and Central Idaho and settle into valleys and low-lying areas, with heavier smoke near active wildfires. Smoke across the Owyhee Mountains and southwest Idaho will remain more localized, with concentrations increasing in valleys and sheltered areas near active fires overnight. By Thursday morning, light smoke and haze will persist across portions of southwest Idaho and the Snake River Plain, while North and Central Idaho remain the most broadly impacted areas.
Daytime mixing and increasing southwest to westerly winds Thursday will improve smoke dispersion across much of the state and begin shifting smoke eastward. Light to moderate smoke will continue across portions of North and Central Idaho, but concentrations should become more variable as winds increase ahead of the approaching trough and dry cold front. Moderate to heavy smoke will remain possible near active wildfires, and stronger winds may rapidly change plume direction and temporarily increase smoke concentrations downwind of fires. South and East Idaho should remain comparatively less impacted outside of localized wildfire plumes and periods of light smoke and haze. The highest AQI levels are expected across North and Central Idaho and near active wildfires, where periods of UNHEALTHY FOR SENSITIVE GROUPS air quality are possible.
