Smoke from dozens of raging wildfires in western Canada caused states across the northwestern US to issue air quality alerts over the weekend. Montana officials said that nearly the entire state was being impacted by the wildfire smoke on Sunday and enacted an air quality alert for over three dozen Montana counties. In Utah, residents were encouraged to avoid outdoor activities, and the smoke from the Canadian wildfires is expected to travel west to east across the US, impacting the northeast early this week. Research has found that climate change is leading to larger, more intense, and frequent wildfires, impacting air quality for communities around the world. (ABC News, CNN, AP, NPR, Axios, New York Times $; Climate Signals: Wildfires)