17 August 2018 — 1212 mdt
Ten days of smoke in the Flathead Valley
On 7 August, the Flathead Valley filled with smoke — and with a couple of exceptions, has remained full of smoke. The concentrations of fine (≤ 2.5 microns) particulates are published online by Montana’s Air Quality Bureau, but the AQB’s graphs only cover only one day (midnight-to-midnight) of data, and thus do not tell the extended story. The graph below displays one-hour averages, but not the health category breakpoints.
