Wildfire Smoke Update
for
Monday, September 24, 2012 3:50 PM

Satellite Photos | Locations and Smoke Conditions

Today's Report and Forecast	Today's Summary
Air quality continues to decline across parts of western Montana this afternoon. Visibility in the Missoula Valley has dropped below 2 miles at times, and in Hamilton, visibility has not been above 2 miles all day. A blanket of at least thin smoke is in the atmosphere over the entire state of Montana today. Areas generally west of the Continental Divide, and near the Divide in the southwestern region, have seen heavy smoke from wildfires. Although fire activity in Idaho and western Montana has been slower in recent days, with the stable air we have had in place, smoke has simply accumulated in the western valleys. Air quality in Missoula is UNHEALTHY, and cumulative particulate concentrations in Hamilton are HAZARDOUS. Cumulative smoke exposures continue to run high west of the Continental Divide, as the Flathead Valley is still UNHEALTHY FOR SENSITIVE GROUPS, Seeley Lake is still UNHEALTHY, and Libby is still MODERATE, though hourly concentrations in these locations are generally only GOOD to MODERATE. Air quality is mostly GOOD across southwestern and eastern Montana this afternoon. A couple weather disturbances will be present this week, which will help to cut down on the stable, stagnant air that we have seen for the last week. Tomorrow through Wednesday, one of those disturbances will pass across the state. Clouds will increase and the air will become slightly unstable. The result will be the chance for a few isolated thunderstorms to develop over the western terrain. Winds will be very light throughout the atmosphere and somewhat variable in direction. However, by tomorrow night, the prevailing wind will once again blow generally from the west, which is typical. This will keep wildfire smoke across western Montana. On Wednesday, there will be a slight chance for light rain across most of the state, with slightly breezier winds. By Thursday, this little weather system will be over eastern Montana. Winds may become breezy by the end of the week and the weekend, which would help to blow smoke out of the area, but would also fan the wildfires and blow new smoke over Montana. In all, the smoke should generally stick around for the week, even if it improves for short periods of time. Looking ahead to the first week of October: we are seeing something in the very long-term forecast models that we haven’t seen for a few weeks and months. We are seeing a potential weather system developing for the middle to end of next week, which may provide cool enough temperatures and enough moisture to nearly put an end to fire season. Confidence is very low in a forecast when it is more than a week away, but one cannot help but feel excited to know that there may be a chance to put an end to the fires and smoke. I will certainly keep you updated, as the forecast can change quickly and often!	Air quality in Missoula is UNHEALTHY, and cumulative particulate concentrations in Hamilton are HAZARDOUS. Cumulative smoke exposures continue to run high west of the Continental Divide, as the Flathead Valley is still UNHEALTHY FOR SENSITIVE GROUPS, Seeley Lake is still UNHEALTHY, and Libby is still MODERATE, though hourly concentrations in these locations are generally only GOOD to MODERATE. Air quality is mostly GOOD across southwestern and eastern Montana this afternoon.
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 2:30 this afternoon. We can see some clouds across Idaho and southwestern Montana, as well as clouds developing over the mountain ranges in southwest Montana and Wyoming. The smoke is difficult to see in this image because it is all over the Montana sky. 




 
This is also a visible satellite image over western Montana and the Idaho panhandle from 1:30 this afternoon. The clouds are at the bottom of the image; the Bitterroot Valley is just to the north of the clouds, in the center of the image; the Mission Valley and Flathead Lake are just north of the Bitterroot. In this image, we can clearly see the “gray blanket” of wildfire smoke over western Montana.




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 

Visibility in the Missoula Valley has been below 2 miles at various times this afternoon due to wildfire smoke.

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

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.