Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

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FXUS64 KMRX 220826

Area Forecast Discussion
National Weather Service Morristown TN
326 AM EST Tue Jan 22 2019

.SHORT TERM...(Today and Tonight)...

Upper ridge will remain across the southern Appalachians today
keeping conditions dry, but allowing plenty of cirrus/cirrus-
stratus to move into the area. Surface ridge will will located
east of the Appalachians allowing the boundary layer jet to become
southerly. Southerly winds of 30-40kts is expected in the
afternoon pulling warmer air back into the Tennessee Valley.

For this evening into tonight, southerly jet will continue to
increase to 50 to 60kts with another mountain wave high wind event
developing this evening through Wednesday. We have issued a high
wind watch for the Mountains and Adjacent Foothills with gusts up to
65-70 kts possible in the favored areas.

The southerly winds will also increase the isentropic lift over the
area with showers moving into southeast Tennessee and southwest
North Carolina overnight. Downslope winds will help keep the shield
of rain from moving into the northern and central valley until

Lows tonight will likely occur by midnight since increasing clouds
and advection of warmer 850mb temperatures allowing temperatures to
warm toward daybreak.

.LONG TERM...(Tuesday through Monday)...

Starting off the long term forecast with a frontal system on
Wednesday. Temperatures during Wednesday will be warm enough that
we will initially only see rain from this weather system. Rainfall
could reach up to 2 total inches with a possibility of localized
flooding. As we get into Wednesday night, the temperature will
drop low enough for areas of moderate to higher elevation, such as
the plateau and the Smokey`s, to start seeing snow. Some minor
accumulation is possible for these areas of under an inch.

Winds will also be a concern during this weather system. Some
downsloping winds along the mountains and foothills could see
sustained wind speeds of 40 mph with even higher gusts. The winds
are expected to calm by Thursday morning as the front moves out of
the forecast area.

Wednesday also looks to have unseasonably high temperatures due
to the warm front out ahead of the frontal boundary, but it will
be back to colder weather by the end of the week. The passing cold
front brings in another very cold airmass that will be relatively
short lived as we return to more seasonal temperatures by the
weekend. Another weather system is expected around midway through
the weekend, although models are currently not in great agreement
with it`s arrival time.


Chattanooga Airport, TN             40  54  32  41 /  60  90  90  30
Knoxville McGhee Tyson Airport, TN  39  57  33  39 /  30  90  90  30
Oak Ridge, TN                       39  55  32  39 /  50  90  90  30
Tri Cities Airport, TN              32  55  33  37 /  10  70  90  60




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