Wildfire Smoke Updates Home | Archived Wildfire Smoke Updates | Today's Air

Wildfire Smoke Update
Tuesday, September 25, 2012 8:31 AM

Satellite Photos | Locations and Smoke Conditions

Today's Report and Forecast Today's Summary
Air quality is still poor across much of western Montana, and even light smoke impacts are making their over eastern Montana. Air quality in Hamilton and the Bitterroot Valley is HAZARDOUS; Missoula is VERY UNHEALTHY. Cumulative smoke exposures are UNHEALTHY in Frenchtown and Butte, and cumulative smoke exposures are UNHEALTHY FOR SENSITIVE GROUPS in Helena, Seeley Lake, and Libby. The air monitor in the Flathead Valley is having some technical difficulties today, so residents there should use the visibility guidelines until the monitor goes back online. Unfortunately to compound the problem, there is dense fog around the Flathead Valley, so visibility guidelines are only effective once the fog has burned off. The last observation in the Flathead from yesterday afternoon was a long-term average that was UNHEALTHY FOR SENSITIVE GROUPS, so it is very possible that conditions are very similar this morning. Cumulative smoke exposures are MODERATE in Great Falls and Sidney, as light smoke is spreading over the northern half of Montana’s plains. The southern half is still mostly GOOD, even in Billings, Bozeman, Dillon, and West Yellowstone.

Wildfire smoke will remain across western Montana today. There will be some slight instability in the air to allow very isolated thunderstorms over the western terrain; but overall, winds will be too light to flush out the valleys. There will be another update this afternoon with the latest smoke conditions and a full forecast.
See "Today's Report and Forecast" (left). There will be another update this afternoon with the latest smoke conditions and a full forecast.
Residents near active fires and under plumes aloft need to remain aware of current conditions and use the visibility guidelines to guide their activity decisions as the situation changes.

Air Quality Bureau
Montana Department of Environmental Quality
Phone: (406) 444-3490
Email: DEQMTSmoke@mt.gov




Real time particulate information is currently available in most of the larger urban areas from MTDEQ's Today's Air website.

Today's particulate report below compares particulate levels received from DEQ's
reporting stations with MTDEQ’s Health Effect Categories.

Locations and severity of PM 2.5 particulate values over the past 24 hours from the time above.
Health Effects Categories City
  Hazardous  Hamilton B24
  Very Unhealthy  Missoula B24
  Unhealthy  Frenchtown B24
Butte B24, B8
  Unhealthy for Sensitive Groups  Libby B24
Helena B24, B8
Seeley Lake B24, B8

 Great Falls B24
Sidney B24


West Yellowstone

B1(x) One-hour BAM value (number of values)
B8(x) Eight-hour average BAM
B24 24 hour  average BAM value
Local impacts in areas immediately adjacent to active fires are expected to exceed some or all of the advisory levels.  DEQ recommends the use of local visibility guidelines to evaluate possible health risks and make informed activity decisions.