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Area forecast discussion 
National Weather Service Salt Lake City Utah
954 PM MDT Thursday Apr 24 2014

Synopsis...a mild southwesterly flow will develop tonight and
increase Friday ahead of the next Pacific storm. This system will
cross the region late Friday through Saturday. A weak trailing
system will cross northern Utah late Sunday.

&&

Discussion...Utah is under a southwest flow aloft this evening as
the ridge axis has shifted east ahead of the upper trough deepening
off the West Coast. A couple of weak disturbances ejecting out ahead
of the main low will push a shallow boundary first into far
northwest Utah later tonight and then across the Great Salt Lake
early tomorrow afternoon. These waves will be accompanied by
increasing precipitation across northern Utah.

Ahead of the main low and south of said boundary...south winds will
pick up tomorrow and become strong and gusty by afternoon. The winds
are not expected to be as strong as with the last storm...but
widespread gusts over 40 miles per hour and blowing dust will be common in this
area. A Wind Advisory is already in place for the valleys of
southern and central Utah.

As the main low continues to carve into Southern California tomorrow
night...the boundary will pivot...retreating north across northern
Utah while cold advection strengthens across southwest Utah. While
precipitation is expected to linger across the north...it will also
begin to spread into southwest and west-central Utah as a result.
Widespread precipitation will then be in store for the area on
Saturday as the storm system slowly crosses the area. Although
significant moisture is expected through Saturday evening with an
inch or more of water over the high terrain...much of this will fall
under a relatively mild airmass of -2 to -5c 700 mb temperature. Snow
levels will remain well off the valley floors while the mountains
will likely see advisory amounts in high-density snow with main
impacts confined to the higher peaks. Will let midnight shift make
the decision on highlights with the morning package. For now...have
updated only to spread evening clouds a bit farther south and to
bump up evening probability of precipitation for a couple of zones.

&&

Aviation...operational weather concerns will remain limited at the
kslc terminal through Friday morning with ceilings remaining above
7000ft. Southerly winds will continue through around 18-20z before a
weak cold front switches winds to the northwest.

&&

Slc watches/warnings/advisories...
Utah...Wind Advisory from 10 am to 9 PM MDT Friday for utz013>016-
019>021.

Wyoming...none.

&&

$$

Cheng

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