Smoke visible from fires in British Columbia

Thanks to Gilbert Sebenste for helping me figure this one out. When checking the visible satellite imagery for the region I noticed a long band of "haze" stretching over parts of the upper midwest, from Minnesota into northern Illinois. It appeared to be smoke, or dust, but I wasn't sure what the original source was. I was unaware of the major fires going on at the moment in British Columbia, which would explain it!

http://www.cbc.ca/canada/story/2010/08/05/bc-fires.html

Here's the initial regional satellite image that made me scratch my head:


Zooming out to the national picture the source is plainly visible!