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Area forecast discussion 
National Weather Service Salt Lake City Utah
347 PM MST Sat Nov 28 2015

Synopsis...a cold upper level low pressure system will remain
over the Great Basin through the remainder of the weekend. High
pressure aloft will settle into the region early next week.


Short term (thru 00z wednesday)...a cold upper low remains
centered over the Utah Wyoming border east of Logan this afternoon. An
area of light snow continues wrapping around the low into portions
of northern Utah while lift associated with a secondary center is
increasing across southern Utah as that feature swings into the southern part
of the state.

Expect areas of light to snow persist across portions of the County Warning Area
overnight through sun as the upper low wobbles around the state.
Most snow amounts should stay around an inch or less each 12 hour
period but this snow will likely stick to untreated roadways again
once the sun sets creating local hazardous travel conditions that
could last into Sun morning until weak insolation thaws pavement
surfaces again.

The upper low shifts east Sun night with one last wrap around
band of light snow forecast for northern Utah. This could persist into
Monday morning before the low moves far enough east for it to end and
could bring another round of Road impacts possibly affecting the
Monday morning commute along the Wasatch front.

Upstream ridging gradually advances into the County Warning Area Monday afternoon through Tuesday
ending the precipitation and allowing skies to clear. Expect valley
inversions to begin developing Monday night with temperatures Tuesday struggling
somewhat in these areas in spite of airmass warming.

Long term (after 00z wednesday)...SW-NE oriented axis associated
with short wave ridging in place will remain overhead Wednesday
prior to shifting east Thursday...this as the pattern once again
amplifies over the eastern Pacific. Not much to note Wednesday as
temperatures aloft will continue to warm /h7 temperatures nosing towards -2 to 0
c by late day/...likely promoting strengthening Low Valley/basin
inversions and hampering potential warming across the lower
elevations. Could see a buildup of valley haze along the Wasatch
front midweek but will have to continue to monitor trends leading
up this.

With the aforementioned easterly shift of the ridge Thursday /and
net amplification over the eastern Pacific associated with the
next evolving trough/...will likely see a solid uptick of
southwesterly flow aloft promoting enhanced valley mixing and
warming trend valley temperatures during Thursday afternoon.

Globals models continue to split this next trough upstream and
overhead late Thursday through Friday...with the southern split
translating across the area prior to closing off downstream in
vicinity of the 4-corners or even further east Saturday. Have
maintained generally slight chance probability of precipitation and a net cooling trend
through that period...but net confidence in detail regarding where
and how strong this split will occur remains on the low side even
with solid model agreement at the time being.


Aviation...periods of light snow will persist over and near
the slc terminal through Sunday. In the near term...IFR to MVFR
conditions are expected through around 23-01z before gradually
improving to VFR as snow decreases. Should in general continue to
see improvement of conditions overnight...but ceilings will likely
remain 6000ft or less. However...occasional low MVFR to IFR
conditions may still develop through the night. With cold
temperatures in place...snow will be able to accumulate on
untreated surfaces...especially after sunset...with up to an inch
overnight. Otherwise...northwest winds should switch to southeast
around 03-04z.


Slc watches/warnings/advisories...


Short term...wilensky
long term...Merrill

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