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Area forecast discussion 
National Weather Service Salt Lake City Utah
444 am MDT Friday Aug 29 2014

Synopsis...high pressure over the region will shift east late
today. A cold front will cross northern Utah Saturday...stalling
across central Utah on Sunday.

&&

Short term (thru 00z tue)...the ridge over the region early this
morning has flattened a little as a weak short wave that crossed
the northern rockies overnight moves off into the northern plains. The
trailing end of this weak wave set off a little convection over
northern Nevada/southwestern Idaho overnight and expect this again today over the northestern
mountains

The ridge axis starts to shift east late today and convection is also
possible over the far northwest as another short wave out ahead of the
main Pacific trough starts to impact the northern Great Basin. This feature
keeps a threat of high based convection going over the northern County Warning Area
overnight tonight through early Sat with a lull Sat afternoon.

Temperatures today should warm an additional 5 degrees or so from
yesterday as the airmass warms somewhat. We overperformed on the
highs yesterday so expect slc to reach 90 today as any cloud cover
looks to hold off until very late afternoon or this evening.

The wave tonight/early Sat does introduce slightly cooler air
into the north but also brings gusty afternoon winds so expect little
change in temperatures Sat from today all but the far north due to
better mixing.

The main portion of the Pacific trough crosses the northern rockies Sat night
sending a stronger cold front through northern Utah with what appears to be
the best chance of showers for northern Utah this weekend in a band along
the front. These could linger into early sun over the northestern County Warning Area but
the wave is past by midday and expect most of the day to be sunny
and dry. Temperatures will be 10-15 degrees cooler over the north but the
cooler air barely reaches the south so expect only slight cooling
there.

Dry stable northwesterly flow then dominates the County Warning Area Sun afternoon into Monday.
Sun night will be clear and cool and Monday should be sunny and dry
with slight warming.

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Long term (after 00z tuesday)...ridge of high pressure will prevail
Tuesday through Thursday with temperatures expected to be slightly
above normal. A trough developing over the western Great Basin
Wednesday through Thursday will cause southwest winds to increase
over western valleys during this time frame. The trough will move
into the central Great Basin Friday with the associated cold front
nudging into extreme northwest Utah. The global models diverge at
this point on the amount of moisture that gets tapped and brought
northward into the region. The ec taps is more aggressive then the
GFS. Low confidence on which solution to follow but have increased
probability of precipitation a little over mainly eastern and southern portions for Friday.

&&

Aviation...the slc terminal will see VFR conditions through the taf
period. Southeast winds are expected to shift to the northwest about
20-21z.

&&

Fire weather...temperatures will be warmer today but with that
warmth a threat of showers and thunderstorms...mainly high
based...will occur this afternoon over the northwest corner and the
northern mountains. The south will remain dry. Another trough and
its associated cold front will move across northern Utah Saturday
night with scattered showers and isolated thunderstorms. Isolated
showers will linger into Sunday with below average temperatures. All
areas will see a warming trend next week with above average
temperatures expected from Wednesday through Friday along with
minimum relative humidity values dipping below 15 percent western
and southeast valleys.

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Slc watches/warnings/advisories...
Utah...none.
Wyoming...none.
&&

$$

Short term...wilensky
long term/fire weather/aviation...struthwolf

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