A quick look at the air quality data shows we have exceeded the National Ambient Air Quality Standard for 24-hour average PM2.5 in several counties including Utah, Salt Lake, Davis, Weber, Cache, and Tooele. This is a regional scale event with a large fraction of Utah's population impacted.
In Salt Lake, our 24-hour average PM2.5 presently sits at about 60 ug/m3. Despite a drop in hourly PM2.5 overnight, there seems to be little reason not to expect the longer term upward trend to continue.
|Source: Utah DAQ|