658 
FXUS65 KSLC 131008
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
408 AM MDT Mon Sep 13 2021

.SYNOPSIS...A weak cold front will stall across central Utah
today, allowing a slightly cooler air mass to spread across the
north. Meanwhile the south will remain warm and dry. A general
westerly flow will follow through mid-week, maintaining warm and
dry conditions. 

&&

.SHORT TERM (Through 12Z Thursday)...Cyclonic flow prevails across
the Pacific Northwest/northern Rockies region early this morning.
A weak shortwave trough embedded within this flow is brushing by
northern Utah/southwest Wyoming, with the associated surface front
having pushed into the far southern Wasatch Front. RAP analysis
shows the associated upper jet extending across northeast NV and
northwest UT, with a region of lift persisting along the nose of
this feature over northern Utah. As such isolated showers and
thunderstorms persist early this morning, and will likely hold on
for another hour or two before this region of ascent moves east by
sunrise. Have included slight chance PoPs east of the Wasatch
Range and north of I-80 early this morning, and will monitor
radar/satellite trends for necessary adjustments should this
stubborn convection persist. 

The surface front will stall across central Utah today, leaving a
slightly cooler and more stable air mass across northern Utah and
southwest Wyoming. Meanwhile warm and dry conditions will persist
south of this boundary, with locally breezy conditions across
southwest Utah this afternoon. Hi-res models indicate convection 
will develop again this afternoon over the high Uintas, otherwise 
conditions should remain dry over the remainder of the area this 
afternoon. 

Height rises under a general westerly flow will result in dry
weather Tuesday and Wednesday, with temperatures running 5 
degrees or so above climo. 

.LONG TERM (AFTER 12Z THURSDAY)...Weak high pressure will allow 
for pleasant weather conditions the latter half of the week. 
Temperatures generally in the mid to upper 80s (with 90s in the 
St. George vicinity) are forecast with little overall change 
through Saturday. Dry conditions are forecast. A pattern change is
noted by Sunday and especially by Monday. This is resulting from 
a broad upper trough digging down from the north and has been a 
consistent trend in models thus far. About a 20 degree high 
temperature spread exists in ensembles early next week at SLC, 
indicating uncertainty in the forecast at this point. By Monday, 
there is only a 25% chance of Salt Lake City reaching 80 degrees 
or higher; a change in the weather pattern indeed. 

.AVIATION...KSLC...High based clouds or clear conditions are 
forecast throughout the forecast period. VFR conditions will 
persist. Light winds are expected at less than 12 knots during the
day and night. 

REST OF UTAH AND SOUTHWEST WYOMING...Clear skies or high based 
clouds are forecast today with dry conditions forecast. VFR 
conditions are anticipated with diurnal fluctuations to winds.

&&

.FIRE WEATHER...A weak cold front will stall across central Utah 
today. To the north of this boundary slightly cooler and more 
stable air will spread across northern Utah. Areas south of the 
front will see warm, dry and breezy conditions, with local 
critical fire weather conditions possible where fuels are 
sufficiently dry. 

A general westerly flow will follow Tuesday and Wednesday 
resulting in warm and dry conditions across the area. The flow 
will become southwesterly during the latter portion of the week, 
maintaining warm and dry conditions, but also bringing the 
potential for gusty afternoon winds across southern Utah. 

&&

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

$$

Seaman/NDeSmet

For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecity

For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php