Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Salt Lake City Utah
1008 PM MDT Friday Oct 24 2014
Synopsis...a cold front approaching Utah will generate strong
southerly winds on Saturday. The front will cross the state Sunday
through Sunday night ushering in a colder airmass.
Discussion...a strong upper ridge is centered over Colorado this evening and
a deep closed low is spinning off the West Coast. Utah is under a
warm dry southwesterly flow in between these features with clear skies and
mild temperatures. The local breezy afternoon south winds are
diminishing but could persist in a few spots overnight. Near
record highs were noted today with a few sites reporting record
The offshore low starts moving inland tomorrow with lowering
heights and increasing southwesterly flow over the County Warning Area. The surface
gradient also tightens up and expect windy conditions across the
County Warning Area from about late morning through late evening. Current Wind
Advisory looks on track and new 00z NAM would support expanding
it into the Salt Lake and Tooele valleys. This would probably be
warranted if remaining 00z guidance supports it as well.
The airmass cools a little with the lowering heights tomorrow and
some high cloudiness out ahead of the epac low moving over the County Warning Area
in the afternoon. All this points to a potential for maximum temperatures tomorrow
to be a little cooler than today. However...the warm airmass in
place and the increasing southerly flow aloft tonight should prevent
temperatures from getting very chilly and a warmer start should bring
maxes up to at least equal todays.
This new NAM is not as amplified with the Pacific trough once it moves
inland as earlier runs and other guidance...now keeping the 500
mb cold air off to our north and not as cold at 700 mb either. It
also is drier than previous and other guidance with barely any precipitation
at all for the County Warning Area either with the initial weak front before dawn
Sunday or the secondary push sun evening. Post frontal winds are also
not as strong. So if other guidance trends towards this solution
we will need to lower probability of precipitation significantly for this event.
For now no short term updates needed.
Aviation...winds at the slc terminal are expected to remain
southerly through the night and Saturday. Winds will increase
Saturday morning becoming gusty after about 15z.
Utah...Wind Advisory from noon Saturday to midnight MDT Saturday night
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