Air quality in the Salt Lake Valley continues to deteriorate. Observations from DAQ sensors and from Trax-mounted sensors operated by the University of Utah are generally between 35 and 60 ug/m3, which is in the unhealthy for sensitive groups category.
Although there are short term ups and downs in PM2.5 concentrations, with values teaching their highest values late in the day through midnight followed by a decline, the long-term trend is upward. That upward trend is actually not due to the inversion getting stronger (once the valley is capped off, further strengthening doesn't matter). Instead, we're in a situation where emissions continue to accumulate in the valley. Further worsening of the air quality will occur through at least the end of the week.
The models are flirting with a trough passage this weekend. I say flirting because much depends on what model and ensemble member you look at. Some have a brush by, others a more direct hit. At this point, it's too soon to say if it will crack this thing, give us at least a partial mixout, or leave the air pollution fully intact. The Euro provides a brush-by to the north, but perhaps enough to stir us up a bit.
|Source: Penn State e-wall|