Smoke Forecast for Thursday, September 4, 2025 10:00 AM

Current Conditions

Montana DEQ is issuing an Air Quality Alert for Beaverhead, Deer Lodge, Granite, Mineral, Missoula, Powell, Ravalli, and Sanders Counties because of elevated particulate levels from wildfire smoke. The alert expires at 9AM Friday, September 5, 2025.

An Air Resource Advisor has been assigned to the Bivens Creek and Cloudrest fires burning near Twin Bridges in southwest Montana.

Behind a cold front, northeasterly winds will drag down smoke from Canadian wildfires into parts of the state on Thursday.

The Ulm Creek fire, burning just west of Trout Creek, Montana, has gained a lot of acreage this week.  It has grown to 1,800 acres and is 0% contained. The Knowles fire burning near Paradise, Montana, has burned 3,822 acres. The blaze is now 52% contained. Firefighters have begun making progress on the Bivens Creek and Cloudrest, burning in the Tobacco Root Mountains. The Bivens Creek fire is now 91% contained, and the Cloudrest fire is 35% contained. The Windy Rock fire, burning 15 miles northeast of Drummond, was very active on Wednesday. It has grown to 5,001 acres and is 2% contained.  The Ransome fire, burning just north of Libby, was less active on Wednesday. It has grown to 649 acres and is 23% contained. There are several active wildfires burning in central and northern Idaho. The biggest of concern for Montana’s air quality are the East, Mire, Rhoda Creek, and Ulm Creek wildfires.

At 9:00 AM Thursday, Butte, Seeley Lake, Frenchtown, Missoula, Miles City, Lewistown, Dillon, Hamilton, Helena, Sleeping Giant, Cut Bank, Columbia Falls, Bozeman, West Yellowstone, Billings, Havre, Glendive, Sidney, Broadus, and Glasgow’s air quality is Moderate. Great Falls and Thompson Falls’ air is Unhealthy for Sensitive Groups.

By Friday afternoon, the High-Resolution Rapid Refresh (HRRR) smoke model shows surface smoke covering much of southwest Montana behind a cold front.

Source: HRRR-smoke

Forecast

A cold front continues to sag slowly south across the state on Thursday. It will bring an end to the unseasonable warmth Montana has experienced the last several days. It will also bring easterly and northeasterly winds to the state, pushing much of the smoke from the numerous wildfires burning in Idaho away from Montana. Unfortunately, strong winds on Thursday will lead to additional fire growth on wildfires in the region. The wind shift will also bring smoke from Alberta and Saskatchewan into the Treasure State. This cooler airmass should stick around through Friday, but winds won’t be nearly as strong.

The ridge of high pressure shifts east towards Montana this weekend, allowing temperatures to quickly moderate. However, this ridge won’t be nearly as amplified as the prior ridge, so temperatures won’t be quite as warm. A southwesterly flow will pump anomalously moist air into the state, setting the stage for scattered showers and storms.

Long-range models keep the southwesterly flow continuing into the following week. This should keep temperatures close to average, while allowing for daily chances for rain and thunderstorms. In general, next week’s pattern should keep regional wildfires in check while reducing smoke production. Stay tuned!

Conditions can change quickly as weather could stimulate active fires and the likelihood of new starts increases. Please keep track of concentrations at todaysair.mtdeq.us or the Fire and Smoke Map.

Thursday morning’s satellite image shows some smoke covering much of the state from numerous regional wildfires in the U.S. and Canada. A cold front is producing clouds over north central and northeast Montana.

Source: NOAA

Tags: Smoke Forecast 2025