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000
FXUS64 KMRX 040816
AFDMRX

AREA FORECAST DISCUSSION
National Weather Service Morristown TN
316 AM EST Thu Mar 4 2021

.SHORT TERM...

For Today, a dry frontal boundary will move south across the
Tennessee valley and southern Appalachians. Due to the plenty
of sunshine and steep low-level lapse rates, good mixing is
anticipated ahead of the boundary. Plenty of sunshine and good
daytime mixing ahead of the boundary will likely slow the
southward progression with some compressional warming anticipated.
Decided to go a couple degress warmer than guidance because of
these factors.

The good daytime mixing will also produce another day of low
afternoon relative humidity. Plan on going several degrees lower
than guidance dewpoints. Relative humdity will drop into the 20s
and near 30 over most of the area this afternoon and early
evening. Will message this concern within the Fire Weather
Forecast.

For Tonight, ridging, dry conditions, and light/calm winds will
allow temperatures to drop with large diurnal temperature swings
continuing.

.LONG TERM...(Friday through Wednesday)...

Models continue to show a rather quiet long term period.  We start
the period under the influence of the Eastern US trough aloft and
surface high pressure extending into our area from the north and
northwest.  A mid/upper level short wave will swing by to our south
Friday night, but should just increase cloudiness especially
southern half of our area Friday into Friday night with any
precipitation suppressed to our south.

Behind this system, the upper trough will shift east and low
amplitude ridging will gradually build over the region aloft. The
area of surface high pressure will drift southeast across our area
and will eventually be centered off to our east/southeast by the
Tuesday/Wednesday time frame. Models do hint at some short wave
energy aloft moving across at some point although they do not agree
on timing, but the air mass looks to be quite dry so we should just
see more high clouds when that occurs.  By Wednesday a cold front
will be approaching so moisture should begin to increase, but it
looks like any precipitation will hold off until after sunset.

Temperatures will start the period near or even a bit below seasonal
normals, followed by a warming trend.

&&

.AVIATION...
06Z TAF DISCUSSION.

VFR conditions throughout the forecast at all TAF sites. Mainly a
wind forecast as a dry frontal boundary moves south across the
region. North to northwest winds will increase today with gusts at
TRI up to 20 mph possible.


&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             69  38  59  37  58 /   0   0   0  10   0
Knoxville McGhee Tyson Airport, TN  64  33  53  32  53 /   0   0   0  10   0
Oak Ridge, TN                       65  33  55  31  54 /   0   0   0  10   0
Tri Cities Airport, TN              60  27  51  24  50 /   0   0   0   0   0

&&

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

$$