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559
FXUS64 KMRX 191928
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
328 PM EDT Sat Aug 19 2017

.SHORT TERM...(Tonight through Monday)...Mostly sunny skies at mid
afternoon Saturday with temperatures in the lower to mid 80s north
and mid to upper 80s south. Winds are light and dew points are 3
to 4 degrees lower for the most part across the region. Area
radars are quiet with the closest showers in southern KY/northern
Tennessee near Clarksville TN. A weak boundary over southwest KY
should lift north tonight and Sunday as ridging aloft strengthens
over the region. Another boundary to the south...the front from
Friday will stay along the southeast US coast. The forecast area
in the middle will be mostly clear and temperatures will warm a
few degrees to the upper 80s to as warm as mid 90s Sunday after
another slightly cooler Sunday morning. Monday not much change
with the ridge pattern with skies again mostly sunny in the
morning and a few clouds in the afternoon. An increase of moisture
by Sunday night will keep lows slightly warmer Monday morning.
Did not change rain chances much Monday with only about a 20
percent chance of afternoon showers and a few storms from
southwest North Carolina and southeast Tennessee northeast along
the Appalachians into Virginia. The showers will be most numerous
from mid afternoon until sunset. The eclipse may act to delay
cloud development until late afternoon or after eclipse time.

.LONG TERM...(Monday night through Saturday)...Models still bringing
another, most pleasant heat busting upper trough into the Eastern
U.S. at mid week. Showers and thunderstorms should become likely
ahead of the associated cold frontal boundary mainly later Tuesday
night into Wednesday. Tried to edge back on pops for the pre-frontal
period during the day Tuesday as the models try to generate some
convection. It looks like it may take a little deeper influx of
moisture and instability to push pops higher with soundings
indicating quite a bit of warm, subsident air from the strong, early
week upper ridge. Any rain is pretty much over by Thursday as the
drier and cooler northerly flow builds in behind the mid week
system. The dry pattern may continue into the weekend, however
models hint at the possibility of a weak upper wave moving across
the area, along with the development of a low level trough on
Saturday, so included some slight and low chance pops for a shower
or thunderstorm here. Temperatures start out several degrees above
normal on Tuesday but mercifully cool off to a few degrees below
normal with the cold front and associated northerly flow developing
Wednesday through the remainder of the forecast.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             68  93  71  92 /   0  10  10  10
Knoxville McGhee Tyson Airport, TN  68  91  69  89 /   0  10  10  10
Oak Ridge, TN                       68  91  70  90 /   0   0  10  10
Tri Cities Airport, TN              62  90  64  88 /   0  10  10  10

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...None.
TN...None.
VA...None.
&&

$$