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000
FXUS64 KMRX 161538
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
1138 AM EDT Tue Apr 16 2024

...New UPDATE...

.UPDATE...
-- Changed Discussion --
Issued at 1102 AM EDT Tue Apr 16 2024

A partly sunny to mostly cloudy sky across the eastern Tennessee
Valley this morning. A few showers/light returns on radar late
this morning over southeast Kentucky and northern Tennessee. A
weak front was located over northern KY, southern West Virginia
and western Virginia north and northeast of the region. A few
showers and later storms are expected to develop south of the
front as a weak shortwave moves across this area combined with the
heating of the day into the lower to mid 80s and good instability.
The stronger storms are expected to be north of the forecast area.
CAM model guidance is still not showing much convection this
afternoon. Will keep the generally slight to low chance pops for
this area, maybe too optimistic. Heating today has been somewhat
delayed by clouds moving in from the west except over the
northeast where they are moving in now. However clouds should
decrease in the afternoon so storms may develop later in the day.
Updated forecast sent.
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&&

.SHORT TERM...
(Today and tonight)
Issued at 236 AM EDT Tue Apr 16 2024

Key Messages:

1. Warm temperatures continue today

2. Chance for showers and thunderstorms in northeast TN and
southwest VA

Discussion:

Currently a fairly warm early morning as increased cloud coverage
has helped keep temperatures elevated overnight. Some lingering
showers and thunderstorms are still present across the frontal
boundary draped across northern KY. Can`t completely rule out a
storm clipping southwest VA if it detaches from the front so will
continue with low end PoP chances, but expect mostly dry conditions
the rest of the morning.

Today will likely be the warmest day of the forecast with highs
expected to climb up into the 80s for almost everyone in the eastern
Tennessee Valley. With how warm temperatures at the surface today,
expect there to be an increase of CAPE in the afternoon/evening
hours during peak heating. This is also around the time at which the
axis is expected to traverse through the region. This combination
may be enough to spark off convection, with the best chances likely
in northeast TN and southwest VA. High Resolution CAMs are fairly
pessimistic on these storms actually materializing, but there is
enough moisture and instability to warrant keeping in the low end
PoP chances for the afternoon/evening.

Another warm overnight is expected as we head into Wednesday, when
the incoming front will begin to spread in more widespread showers
and thunderstorms after sunrise.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 236 AM EDT Tue Apr 16 2024

Key Messages:

1. Increasing rain chances with showers and thunderstorms Wednesday.
A break in the rain Thursday. Rain chances increase with a chance
for more thunderstorms Friday and Saturday.

2. Strong southwesterly winds are expected on Wednesday with gusts
up to 30 mph possible in most locations.

3. Turning much cooler Sunday and Monday behind cold front.
Lingering rain chances through at least Sunday with slowing of
front.

Discussion:

By Wednesday morning, the ridge is over the East Coast and a closed
low is moving into MN/WI. The trough extends through the Ohio
Valley. The cold front begins to stall and weaken as it approaches
the region on Wednesday. The front seems to fizzle out before
reaching our area. There is little to no wind shift and dew points
barely decrease by Thursday. CAM guidance shows a wave of showers
and weak storms moving through on Wednesday. The biggest impact with
this system will be strong southwesterly winds on Wednesday with
gusts up to 30 mph possible in most locations. Winds will be
slightly higher in the mountains with gusts of 35 to maybe 40 mph
possible at times. HREF has 850 mb winds between 30 and 45 knots
across the region, although mixing conditions will not be ideal with
cloud cover and WAA expected.

Thursday will be dry with a weak ridge in place. The next system
starts to move in Thursday night as a weak low moves into the
Tennessee Valley with zonal flow aloft. The best chance for showers
and storms with this system will be Friday. Fairly low chances for
showers and storms will linger through Saturday and Sunday as a
boundary lingers south of the region. Cooler temps on Sunday and
Monday behind the front.

&&

.AVIATION...
(12Z TAFS)
Issued at 637 AM EDT Tue Apr 16 2024

At KTYS/KCHA expect VFR conditions with some increased winds in
the afternoon hours and some passing mid/high clouds. At KTRI
there is a slim chance of an afternoon thunderstorm developing in
northeast TN or southwest VA. Have introduced a PROB30 during the
most likely time for these storms to develop, but generally expect
VFR conditions for this TAF cycle.

&&

.PRELIMINARY POINT TEMPS/POPS...
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Chattanooga Airport, TN             86  65  78  63 /   0  10  50  20
Knoxville McGhee Tyson Airport, TN  85  65  77  63 /  10  10  30  20
Oak Ridge, TN                       84  65  77  62 /  20  10  40  20
Tri Cities Airport, TN              81  61  78  60 /  30  10  30  20
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&&

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

$$

SHORT TERM...TD
LONG TERM....McD
AVIATION...