Air quality is MODERATE in most western valleys on Tuesday morning due to inversions currently in place. These inversions are not super strong, with the valleys being around 10 degrees colder than the nearby ridgetops. Currently air quality is MODERATE in Libby, Columbia Falls, Thompson Falls, Seeley Lake, Frenchtown, Missoula, Hamilton, Dillon, Butte, Helena, Great Falls, Malta, and Billings.
The good news (at least from an air quality perspective) is that these impacts are not expected to last long, especially for valleys close to the Continental Divide. Increased winds are expected to move into the area later this afternoon, helping to clear out the valleys. Parts of Northwest Montana, down through Missoula may struggle until later tonight to break out from under the inversions. By tonight, yet another storm system will move in, bringing light snow showers to the region. The trough of low pressure bringing this storm system will remain over the region through Thursday, with a prolonged chance of snow showers. Overall, air quality should be generally good once/if the inversions break today, with brief periods of MODERATE air quality through Thursday afternoon.
A brief lull in active weather on Thursday night into Friday could cause overnight inversions to return to many western valleys. More widespread MODERATE impacts are possible Friday morning. As has been the case for the past few weeks, these impacts will likely be brief with another weather system expected for the weekend. Overall, this cold, snowy and occasionally windy pattern is expected to bring generally GOOD air quality, with brief periods of MODERATE air quality in between weather systems. It looks like we will be under this pattern for the foreseeable future.