Blessings and Curses

Early season snow is of course a blessing for the mountains, but it can be a curse here in the valley.

Valley snow leads to stronger and more persistent cold pools (a.k.a. inversions).  The buildup of pollution over the past couple of days is quite evident looking south over the Salt Lake Valley this morning.

The morning sounding from the Salt Lake City airport shows a stable, near isothermal (i.e., constant temperature) airmass extends from the valley floor to about 750 mb, or about 1000 m above the valley floor.  We're pretty much cutoff from the clean air above.

Source: NOAA/NWS/SPC

Fortunately this will be a short-lived event as the flow aloft is expected to increase tonight and will probably be strong enough tomorrow to at least stir things up and keep the pollution levels from getting annoyingly high.