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Wildfire Smoke Update
for
Tuesday, September 18, 2012 3:53 PM

Satellite Photos | Locations and Smoke Conditions


Today's Report and Forecast Today's Summary
Weather conditions today are more conducive to fire activity than they were yesterday or in the days to come. Winds are gusty in many places across Montana and even southern Idaho as a dry cold front and weak weather disturbance pass across the region. Smoke plumes, though small, are visible on satellite images this afternoon. Air quality is being impacted from all of this wildfire smoke across much of the western half of the state. Hourly particulate concentrations have reached UNHEALTHY levels in Missoula, Frenchtown, and Hamilton. Air quality has become UNHEALTHY FOR SENSITIVE GROUPS in Butte and West Yellowstone, and hourly particulate concentrations in Helena have reached MODERATE levels, and are on the rise. The Forest Service has also placed a temporary monitor in Dillon; the latest hourly observation is MODERATE there, with cumulative exposures that are UNHEALTHY. Hourly concentrations in Bozeman and Great Falls have remained GOOD today, but cumulative concentrations have reached MODERATE levels. Northwestern Montana and Seeley Lake continue to be GOOD today. Across the hi-line, air quality should be GOOD, and the rest of eastern Montana is GOOD to MODERATE.

Smoke continues to blow in from Idaho and as far away as Washington and Oregon. Fire conditions have been a bit more dangerous today, but those will start to dissipate tonight and through tomorrow morning. Winds may still be gusty across southeastern Montana late tomorrow morning, but overall, winds should calm down by Wednesday. This is in part because the weather disturbance and cold front will be out of the area, but also because the large ridge of high pressure will bring its center slightly closer to Montana. Under this ridge of high pressure, the air is very stable, stagnant, warm, and dry. Winds are also very light, which should help to reduce the severity of the fire activity, as well as aiding the firefighters in containment efforts. However, for the smoke that already exists across much of southwestern Montana and even west-central locations, this means that poor dispersion (the atmosphere’s ability to mix out and get rid of the smoke) will keep the smoke in the region. Smoke will only clear very slowly along the very edges of the smoke boundary. For places like Great Falls, Helena, and Bozeman, this means that smoke conditions will improve, but somewhat slowly. This also means that for the Bitterroot Valley and the valleys of far southwestern Montana, the smoke will remain. The weather pattern stays very consistent through the weekend, so similar conditions can be expected day after day. For another day, there is no sign of rain in the forecast to bring fire season to an end.
Hourly particulate concentrations have reached UNHEALTHY levels in Missoula, Frenchtown, and Hamilton. Air quality has become UNHEALTHY FOR SENSITIVE GROUPS in Butte and West Yellowstone, and hourly particulate concentrations in Helena have reached MODERATE levels, and are on the rise. The Forest Service has also placed a temporary monitor in Dillon; the latest hourly observation is MODERATE there, with cumulative exposures that are UNHEALTHY. Hourly concentrations in Bozeman and Great Falls have remained GOOD today, but cumulative concentrations have reached MODERATE levels. Northwestern Montana and Seeley Lake continue to be GOOD today. Across the hi-line, air quality should be GOOD, and the rest of eastern Montana is GOOD to MODERATE.
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




This is the visible satellite image from 2:45 this afternoon. You can see the smoke across the Idaho panhandle which is blowing across western Montana, creating the very poor air quality conditions.  

This is the visible satellite image from 2:45 this afternoon. You can see the smoke across the Idaho panhandle which is blowing across western Montana, creating the very poor air quality conditions.


 
Unhealthy conditions have been monitored in Missoula this afternoon. The smoke is so heavy on this webcam that looks across the city that the mountains just on the other side of the valley are not visible at all.

Unhealthy conditions have been monitored in Missoula this afternoon. The smoke is so heavy on this webcam that looks across the city that the mountains just on the other side of the valley are not visible at all.


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).

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. Green represents thin smoke, yellow is moderate smoke, and purple is dense smoke. 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 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  
  Very Unhealthy  Hamilton B24, B8
  Unhealthy  Missoula B8, B1
Frenchtown B1
  Unhealthy for Sensitive Groups  West Yellowstone B24, B8, B1
Butte B24, B8, B1
Helena B24
  Moderate

 Bozeman B24
Great Falls B24, B8
 

  Good

 Libby
Flathead Valley
Sidney
Billings
Seeley Lake
 

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.