2006 Forest Fire Air Quality Updates
September 5, 2006
10:00 AM
Current Situation
The Big Sky is still choked with smoke this morning. Residual smoke from the last several days is still lingering over the state under a persistent high pressure ridge. Strong inversions have trapped the smoke in the valley near the active fires producing dangerous levels of smoke. Bozeman and the Gallatin Valley are at VERY UNHEALTHY this morning as smoke has continued to drain down into the valley from the east. The Paradise Valley, the Yellowstone River valley between Livingston and Columbus and the Boulder River valleys are all packed with smoke this morning and conditions there are also expected to be VERY UNHEALTHY or even HAZARDOUS. Very little improvement is expected today in the worst areas and many areas under the smoke aloft will be getting significantly worse later this morning and this afternoon. See the forecast below for details. All residents are strongly cautioned to pay attention to the conditions in their area and to use the VISIBILITY GUIDELINES to determine smoke levels in their area and guide their activity decisions.
Morning satellite photo centered on Great Falls
WeatherBug web cam photo of Livingston, MT 59047 by Pat Gilligan
DEQ web cam facing north towards the "Sleeping Giant" mountain
MODIS Active Fire Mapping Program
This morning’s analysis from NOAA's satellite services division shows the active fires in Montana and the smoke plumes combining and spreading downwind (the analyzed smoke is based on yesterday’s satellite coverage, the fire detects are based on last nights satellite coverage).
Red indicates hot spot detected. Grey represents smoke seen by satellite. Fire
size is exaggerated for visibility at this scale. To identify individual fires on graphic above go
here: http://activefiremaps.fs.fed.us/lg_fire2.php
Real time particulate information is currently available in most of the larger urban areas from several different sources including: DEQ run PM-10 BAMS and PM2.5 BAMS, NWS ASOS visibility monitors, and USFS remote access Nephelometers and BAMS.
This morning’s smoke report is below, comparing particulate levels where we have information to MDEQ’s Forest Fire health advisory levels. Smoke Categories
Updated 10:00 AM September 5, 2006
Locations and severity of forest fire smoke reports since midnight of the date above at reporting stations.
| Smoke Conditions | City |
|---|---|
| Hazardous | |
| Very Unhealthy | Bozeman Vis(8) Mill Creek area (est) Derby Fire area (est) |
| Unhealthy | Butte T24 |
| Unhealthy for Sensitive Groups | Missoula T24 Helena Vis(8) Livingston Vis(8) West Yellowstone Vis(1) |
| Moderate | Libby T8 Whitefish T8 Kalispell T8 Polson T8 Missoula T8 Hamilton T8 Great Falls |
| Good |
|
T1(x) |
One-hour TEOM value (number of values) |
| T8(x) | Eight-hour average TEOM value (number of values) |
| T24 | 24 hour average TEOM value |
| Vis(x) | Visibility value (number of hours) |
| Vis(am/pm) | Visibility value from twice/day reporting stations |
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.
Forecast
The ridge overhead has started to retrograde very slightly to the west. This is bringing the beginnings of a northwest flow aloft although surface wind east of the divide will continue easterly another day at least. With the northwesterly flow, the smoke is starting to spread into eastern Montana and Wyoming. Many of these areas will see very hazy skies today and will be impacted by the smoke aloft as it mixes down this afternoon. The areas currently being heavily impacted by local smoke (Bozeman, Livingston, Big Timber, Columbus) will see some improvement this afternoon as the inversions mix out and the smoke has more room to disperse. Conversely, many other areas with smoke aloft that are seeing improved conditions at the surface this morning with the inversion trapping the smoke aloft will see dramatic increases of smoke levels about noon as the smoke mixes back down to the surface. With the westerly flow aloft starting up, Bozeman may look a little better tomorrow. The extended forecast is not promising much relief from the hot, dry weather. This will keep the fire activity up and more smoke will be on our way. There is a big band of smoke in Canada over eastern British Columbia and western Alberta that will be moving across the state with the northwest flow today and tomorrow. Once that plume has passed, if the ridge axis stays to the west, cleared air could start into the state from the northwest tomorrow. Smoke conditions will continue to be locally variable and dangerous conditions are possible in many areas. Residents are strongly cautioned to check there local conditions using the visibility guidelines to guide their activity decisions as the situation changes.
John Coefield
Meteorologist
MDEQ
