Good air quality continues - last post for the season hopefully!

This will be our last blog post for the season (fingers and toes crossed). Air quality has remained in the GOOD to MODERATE range across the state and is forecast to stay that way for the forseeable future.

Over North Idaho, light smoke and haze will linger through the day with limited clearing this afternoon before more light to patchy smoke and haze moves in from Washington and remains overnight. Central Idaho will see limited clearing of the light smoke and haze this afternoon before more light smoke and haze drifts in from Washington this evening and lingers overnight. Light smoke and haze in South Idaho will see limited clearing this afternoon as well with light smoke and haze remaining overnight. Winds will shift more southerly and easterly tomorrow afternoon, helping to clear out regional haze and smoke across Idaho. With winds expected to increase across the region on Thursday and Friday, smoke production could ramp up for fires in Idaho’s Central Mountains and in central Washington. As temperatures decrease tonight, lingering smoke and haze across Idaho will become trapped under surface temperature inversions and settle in valleys and low-lying areas which will raise local AQI levels until the inversions break later in the morning. The highest AQI levels will be seen around those fires localized to the Central Mountains and North Idaho. Those areas could experience brief periods of UNHEALTHY FOR SENSITIVE GROUPS.

NOAA GOES-West GeoColor (true color) visible satellite image captured at 15:16 UTC (9:16 a.m. MDT) on 22 September 2025 shows isolated clouds across the elevated terrain of Idaho with valley fog in the Panhandle. Smoke and haze is visible over central Washington drifting southeast with smoke and haze over the Clearwater Basin.

Have a happy, relatively smoke free weekend

More of the same today. GOOD to MODERATE air quality with some possible UNHEALTHY FOR SENSITIVE GROUPS areas near fires in central and north Idaho.

Limited clearing of smoke expected in the afternoon before smoke and haze moves back in overnight. Smoke and haze lingering when temperatures decrease tonight will become trapped under surface inversions and settle in valleys and low-lying areas until the inversions break the next morning.

HRRR-NCEP Near Surface Smoke initialized 11Z (5 a.m. MDT) 19 September 2025 and valid at 6 p.m. MDT 19 September 2025 shows light smoke and haze across Idaho moving in from Washington, Montana, and British Columbia. Smoke production from the wildfires in the Central Mountains and North Idaho has been dampened by recent weather, but those fires are still generating light smoke and haze. Models have been picking up on crop residue burning in Central and North Idaho.

Look for limited clearing this afternoon

More GOOD to MODERATE air quality today! Areas near fires local to the Central Mountains and North Idaho could experience brief periods of UNHEALTHY FOR SENSITIVE GROUPS.

Across the state, limited clearing of light smoke and haze this afternoon. North and central Idaho can expect more light to patchy smoke and haze to move back in this evening. As temperatures decrease tonight, lingering smoke and haze across Idaho will become trapped under surface temperature inversions and settle in valleys and low-lying areas which will raise local AQI levels until the inversions break later in the morning.

NOAA GOES-West GeoColor (true color) visible satellite image captured at 15:26 UTC (9:26 a.m. MDT) on 18 September 2025 shows clouds over California and Nevada slowly drifting north. Smoke and haze is visible over northeastern Washington, along with western Washington.

Good to Moderate air quality expected today

Over North Idaho, light smoke and haze will linger through the day with limited clearing this afternoon before more light to patchy smoke and haze moves in from Washington and British Columbia and remains overnight. Central Idaho will see light smoke and haze drift in from Montana this afternoon and linger overnight. Light smoke and haze are entering the Snake River Plain through East Idaho this morning from the East Central Mountains and Montana. The easterly afternoon winds will nudge the light smoke and haze towards the Treasure Valley. Light smoke and haze will linger over South Idaho overnight. As temperatures decrease tonight, lingering smoke and haze across Idaho will become trapped under surface temperature inversions and settle in valleys and low-lying areas which will raise local AQI levels until the inversions break later in the morning. With warmer and drier conditions forecasted for the future, look for smoke production to possibly increase towards the end of the week. The highest AQI levels will be seen around those fires localized to the Central Mountains and North Idaho. Those areas could experience brief periods of UNHEALTHY FOR SENSITIVE GROUPS. All other areas of the state should be GOOD to MODERATE.

NOAA GOES-West GeoColor (true color) visible satellite image captured at 15:01 UTC (9:01 a.m. MDT) on 17 September 2025 shows a few areas of fog and low clouds in the Clearwater Basin and North Idaho with light smoke and haze seen over the Idaho Panhandle, the Clearwater Basin, and the Snake River Plain.

Better air quality continues

Much like yesterday, today's air quality is forecast to be GOOD to MODERATE aside from areas near fires in North Idaho and the Central Mountains where you could experience brief periods of UNHEALTHY FOR SENSITIVE GROUPS.

Over North Idaho, light smoke and haze will linger through the day with limited clearing this afternoon before more light to patchy smoke and haze moves in from Montana and British Columbia and remains overnight. Central Idaho will see light smoke and haze drift in from Montana this afternoon and linger overnight. Light smoke and haze over southwestern Idaho will clear this afternoon. Light smoke and haze will drift southward out of the East Central Mountains and Montana this afternoon into East Idaho and slowly drift across the Snake River Plain this evening and linger overnight. As temperatures decrease tonight, lingering smoke and haze across Idaho will become trapped under surface temperature inversions and settle in valleys and low-lying areas which will raise local AQI levels until the inversions break later in the morning. With warmer and drier conditions forecasted for the future, look for smoke production to possibly increase towards the end of the week.

NOAA GOES-West GeoColor (true color) visible satellite image captured at 15:31 UTC (9:31 a.m. MDT) on 16 September 2025 shows fog and low clouds over mountain valleys in Central and North Idaho with light smoke and haze over North Idaho and the Clearwater Basin.