The first big fires of 2007 in Idaho blew smoke across uninhabited Central Idaho and into the Bitterroot Valley of Montana on July 9. More and more fires started in Idaho and then throughout western Montana. The fires are of all sizes, but a large number are over 50,000 acres.
On my trip there last week I couldn’t find clean air anywhere south of Glacier National Park. While only some of the fires were actively burning new territory, diffuse smoke was rising all over the large swaths already inside the fire perimeters. This came from creeping, smoldering, individual trees (such as red lodgepole torching) and few runs. This made for few visible plumes, but omnipresent smoke.
I stayed one night at a motel in Hamilton, and I asked the night clerk about it. She said the smoke has been nearly continuous since July 9 (a few clear days). The smoke was hardly confined to the Bitterroot Valley, but filled almost all the Western Montana valleys and well as the mountain air and the plains to the east for a ways.
The year 2000 was a huge fire year and 2001 pretty big too. With just a few exceptions, Western Montana has been covered with smoke partially or entirely much of every summer since 2000. This has got to affect recreation and the economy — a dream retirement home in the Big Sky with the sky dirtier than in any city?
The fires will return too — not in an unusually wet year, but the trees are so stressed from lack of water and resulting attack by insects and disease, that they are going to burn for a long time in every dry and even normal precipitation year.