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

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FXUS64 KMRX 220830
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
330 AM EST Mon Jan 22 2018

.SHORT TERM...(Today and Tonight)...A challenging forecast this
morning. For example, there is a 30+ degrees temperature
difference between the Tri-City airport (34 degrees) and Camp
Creek (59 degrees). The reason for such a large difference is a
short distance is Tri-City is calm and decoupled allowing
temperature to drop, but Camp Creek remains well mixed with down-
slope winds off the Mountains.

Increasing low-level jet ahead of a deep upper trough over the
mid-west will continue to enhance the downslope winds with a
Mountain Wave event anticipated over the Mountains, especially far
eastern Tennessee Mountains and foothills. Have issued a wind
advisory for these areas. Gusts of 50-55kts are possible,
including the Camp Creek area.

Another challenge is how much convection to expect with frontal
boundary late today and tonight. Currently, a solid band of
showers and embeded thunder of western Tennessee. Short range high
resolution models show this band weakening and dissapating as it
approaches east Tennessee. This is likely due to the down-slope
winds and initially dry/stable airmass. However, as frontal
boundary moves into the area late today and this evening short-
range models show redevelopment of showers and possibly
thunderstorms south.

Convection will quickly end from west to east overnight as airmass
drys behind frontal passage. May see rain showers change over to
flurries across the highest peaks before ending.

.Long Term (Tuesday through Sunday)...Deep upper low shifts very
slowly east from the Eastern Lakes across New England from Tuesday
into Wednesday. Enough short wave lift and moisture present in the
northwest flow behind the departing low to generate some sprinkles
and possibly a couple snow showers in the highest terrain over
Southwest Virginia and Northeast Tennessee through this period.
Drier westerly flow brings an end to the precip for a pleasant, but
cool couple of days during the middle of the work week. The chilly
air will gradually be replaced by a milder southerly flow ahead of
the next rain producing system due in the region over the weekend.
There is uncertainty concerning the details of the weekend storm
system in terms of strength and timing, so just broad brushed some
relatively high pops for showers for this part of the forecast. The
good news is the strengthening southerly flow leads to above normal
highs despite the decent chance of rain over the weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             62  40  48  31 /  90  70  10  10
Knoxville McGhee Tyson Airport, TN  64  41  46  29 /  60  80  20  10
Oak Ridge, TN                       62  40  46  30 /  80  70  20  10
Tri Cities Airport, TN              63  41  46  27 /  20  80  30  20

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...None.
TN...Wind Advisory from 10 AM this morning to 4 AM EST Tuesday for
     Blount Smoky Mountains-Cocke Smoky Mountains-Johnson-
     Northwest Carter-Sevier Smoky Mountains-Southeast Carter-
     Southeast Greene-Southeast Monroe-Unicoi.

VA...Wind Advisory from 10 AM this morning to 4 AM EST Tuesday for
     Wise.

&&

$$





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