The weather disturbance that moved slowly across the state yesterday helped to clear at least some of the smoke out of central and eastern Montana. That broad area of heavy, high-altitude smoke is not as visible today. Air quality is GOOD across northern Montana. In southwest Montana, our fires as well as fires in Idaho continue to produce smoke, and the smoke is MODERATE to UNHEALTHY FOR SENSITIVE GROUPS in much of Beaverhead County. The southern Bitterroot Valley is also seeing MODERATE long-term smoke conditions, thanks to now a few fires in the Bitterroot National Forest. There are multiple fires in the Bob Marshall and Scapegoat Wildernesses, which are starting to impact the Swan Valley. The weather disturbance helped to clear out some smoke from the fires in southeastern Montana. Monitoring stations and webcams confirm that generally, there is less smoke over the area. By early this afternoon, smoke impacts are mostly MODERATE to UNHEALTHY FOR SENSITIVE GROUPS, save for towns immediately next to the fires, which are still UNHEALTHY.
The weather disturbance that moved through yesterday was the last instance of moderate to good dispersion that we will see for several days. A stagnant ridge of high pressure has moved in today. Skies are clear, except for remnant clouds moving east across northeastern Montana. Hot, dry air is pushing over the state. Red Flag Warnings are in effect for southeastern Montana and in the northern counties off the Rocky Mountain Front. Some breezy gusts are already mixing to the surface early this afternoon, and relative humidities are dropping below 20-25% in the plains. As temperatures heat up near 100 degrees for the next two days, and especially tomorrow afternoon, relative humidities will be very low and dangerous. Dispersion will be mostly poor, as smoke that is produced here and in neighboring states upwind will likely create a cumulative haze in the sky. The forecast will remain persistent through the weekend, except for the slight possibility of isolated, late-afternoon thunderstorms towards the end of the week and weekend. |
The weather disturbance that was slow to move across the state yesterday has cleared some of the high-level smoke out of the air for now. There are still some very smoky regions of the state, like in the southwest (from fires in Idaho and the Bitterroot National Forest) and in the southeast (from large fires in southeastern Montana counties). Smoke impacts in these areas range from MODERATE to UNHEALTHY, especially near the southeastern fires. Red Flag Warnings are in effect for southeastern Montana and northern counties off the Rocky Mountain Front, for some gusty winds and low relative humidities. This hot, dry pattern will continue for at least the rest of this week, when relative humidities will be very low in the afternoons, combined with some strong gusts. The overall weather pattern will be quite stagnant under a broad ridge of high pressure, so air quality may get worse as the week goes on, and a smoky haze may be the norm across much of the sky. |