551
FXUS64 KMRX 211127
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
727 AM EDT Tue May 21 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 310 AM EDT Tue May 21 2024

Key Messages:

1. Most locations will be dry, but there may be a few isolated
showers/thunderstorms today mainly along the eastern mountains.

Discussion:

Yesterday was so good we have elected to copy paste the weather for
today! The 850 mb ridge axis looks to remain centered over the
western Carolinas with only a weak shortwave passing aloft. HREF
depicts plenty of sun, some low level cumulus bubbling in the
daytime heat, and a couple spotty showers or thunderstorms in the
afternoon hours over the elevated terrain, primarily the mountains
along the North Carolina border. Tonight mostly clear skies to start
with some higher clouds moving in late will allow for temperatures
to fall to slightly warmer lows by the morning, with some patchy
fog possible.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 310 AM EDT Tue May 21 2024

Key Messages:

1. Mostly dry through Wednesday night, with daily chances for
showers and storms Thursday into early next week.

2. Temperatures will generally remain near to slightly above normal.

Discussion:

We start the period with an upper trough over the north-central
CONUS and an upper ridge to our east. A low pressure system near the
Western Great Lakes will be tracking north into Canada, and a
slowing cold front will be located across the Ohio River Valley
southwestward into the ArkLaTex region.  This front will stall out
to our north and west Wednesday, and we should stay dry for the
start the of the period Wednesday into Wednesday night.

By Thursday, the flow aloft will become quasi-zonal and the
combination of the remnants of the old frontal boundary over the
region and a series of short waves moving through the flow will
bring an unsettled pattern for the remainder of the long term
period, with chances for showers and thunderstorms each day Thursday
through Monday.  Ensemble data generally shows mean SBCAPES in
excess of 1000 J/kg at times especially during the weekend and mean
PW values often greater than 1.3 inches. While timing and details of
each short wave are still uncertain at this time, there will be the
potential for some stronger storms at times and localized flooding
will also be possible given the multiple rounds of precipitation.
Current total QPF for the Thursday through Monday period generally
ranges from 1.5 to 2.5 inches.

While there is the possibility of a cloudier/rainier period
occurring during the day which could hold temperatures down a bit,
temperatures overall are expected to run near to several degrees
above normal for the long term period.

&&

.AVIATION...
(12Z TAFS)
Issued at 653 AM EDT Tue May 21 2024

Should be VFR through the period for TYS and CHA with light winds
during the day and night. Isolated TS possible in East Tennessee
again today, though unlikely near the terminals. Another round of
VIS restrictions from patchy fog possible, though highly
uncertain, late at TRI between 09z and 12z.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             88  66  88  68 /  10  10   0  10
Knoxville McGhee Tyson Airport, TN  85  64  85  66 /  10  10  10  10
Oak Ridge, TN                       86  64  85  67 /  10  10  10  10
Tri Cities Airport, TN              83  61  85  63 /  10  10  10  10

&&

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

$$

SHORT TERM...Wellington
AVIATION...Wellington