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000 
FXUS65 KSLC 212232
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
332 PM MST Thu Nov 21 2019

.SYNOPSIS...A low pressure system will slowly depart the area
today. High pressure will build into the Great Basin for the
weekend followed by a more active pattern next week. 

&&

.SHORT TERM (Through 00Z Monday)...A weakening upper level low is
currently nearing the Arizona/Nevada border this afternoon. Weak
showers have moved into southwestern Utah along the northeastern
quadrant of this low. Isolated showers also continue across
portions of northern Utah. 

All winter weather headlines have expired or were cancelled
slightly early as any additional accumulation is expected to be
minimal. Easterly canyon winds have also decreased below any
headline level threshold. Expect there may be a few pockets of 
fog tonight in normally prone areas. 

As this upper level low shifts eastward and continues to weaken,
showers will largely end this evening. Heights will gradually
build Friday as upper level ridging builds into the area for the
weekend.

Attention will then turn to the long term forecast period where 
several storms that may impact peak holiday travel will be 
discussed.

.LONG TERM (After 00Z Monday)...Latest GEFS ensemble mean now in 
line with EPS in digging a trough along the West Coast by midweek, 
cutting it off, and finally ejecting it into the Great Basin in the 
latter half of the next week. This scenario would produce impacts 
for anyone traveling across Utah over the Thanksgiving period. 

In advance of the mid-to-late week system, a disturbance will brush 
across the Great Basin from the northwest on Monday. This system 
will bring increasing PoPs north but also bring in cold air in 
advance of the second system. Northern mountains will see a burst of 
snow Monday and Monday night along and behind the cold front 
associated with this first system. Moisture will not be as plentiful 
and this will be a quick hitter, keeping precipitation amounts on 
the low side. 

The details on the timing and strength of the second system is much 
more uncertain. Right now the associated baroclinc zone (the front) 
is expected to move into the state from the west around Wednesday. 
Wednesday and Thursday look wet with snow reaching valley floors 
except for the deserts in the south where rain will fall.

All in all...look for a wet and cold period next week with potential 
travel impacts. Be sure and keep up with the forecast as details 
become more clear. 

&&

.AVIATION...Northerly flow at the SLC terminal should weaken and become 
southeast around 06Z to 08Z. There is a 30 percent chance of below 
VFR ceilings from 10Z to 15Z. Otherwise expect VFR conditions at the 
terminal.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&

$$

Kruse/Billingsley

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