-- Discussion containing changed information from previous version are highlighted. --
765
FXUS64 KMRX 220539
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
139 AM EDT Wed May 22 2024

...New AVIATION...

.UPDATE...
Issued at 1028 PM EDT Tue May 21 2024

Minor tweaks to sky cover this evening as convective debris cloud
from activity over the Mississippi River Valley keeps marching
across middle Tennessee. Otherwise, simply blended recent hourly
temps with the previous forecast as all else remains well on track.

&&

.SHORT TERM...
(This evening through Wednesday)
Issued at 251 PM EDT Tue May 21 2024

Key Messages:

1. Mostly dry through Wednesday with above normal temperatures.

Discussion:

A moderate CU field is in place across the east TN mountains this
afternoon. Isolated showers and storms should begin to pop up
shortly and persist until this evening. Otherwise, quiet overnight
along with mild overnight temps.

Tomorrow, ridging begins to shift east as an upper trough approaches
from the northwest. High pressure hold strong across the Gulf
though, and the cold front slows down and remains to our north and
west. Because of this, we should remain mostly dry , other than some
slight chance POPs across the Cumberland Plateau, east TN mountains,
and southwest VA during the afternoon hours.

&&

.LONG TERM...
(Wednesday night through next Tuesday)
Issued at 251 PM EDT Tue May 21 2024

Key Messages:

1. Daily chances for showers and thunderstorms Thursday into
early next week.

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

Discussion:

The couple of days of nice weather will come to an end late
Wednesday night into Thursday, as troughing begins to extend across
the northern US and we undergo a quasi-zonal flow pattern the rest
of long term period into next week. Daily chances of showers and
thunderstorms will be possible Thursday through Memorial Day
weekend, and even into early next week. Shortwave ripples within
the flow will cycle west to east, providing the support needed
for the development of unsettled weather. A stationary front that
will hang to our north and eventually south of us through
approximately Friday, will also aid precipitation chances as
well.

MLCAPEs through Saturday will be in the hundreds to low thousands
J/kg. The one day that does stand out, however, is Sunday when a
potentially more potent shortwave rounds the trough to our north.
MLCAPEs show values up to and over 2000 J/kg Sunday afternoon. SPC
is already highlighting this set-up in their outlook, where
western parts of our CWA are within the 15 percent oval.

Generally, each day may run the risk of thunderstorm wind gusts,
hail, and flooding from repeated rounds or heavy rain rates.
Specifics as far as strong to severe thunderstorm potential is too
early to know as timing of the shortwaves will play a role. With
no real southerly flow, temperatures will remain around to just
above normal through the period.

&&

.AVIATION...
-- Changed Discussion --
(06Z TAFS)
Issued at 132 AM EDT Wed May 22 2024

VFR through the period expected at all TAF sites with light winds.
Patchy fog near TRI possible between 08z and 12z but not expecting
impacts. An approaching weather system late in the period will
serve to increase high and midlevel cloud coverage, but chances
for a shower or thunderstorm remain very low and are excluded from
a mention in the TAF.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Chattanooga Airport, TN             88  69  86  68 /  10  20  30  20
Knoxville McGhee Tyson Airport, TN  84  67  81  66 /  10  20  60  30
Oak Ridge, TN                       83  67  80  65 /  10  30  70  40
Tri Cities Airport, TN              83  63  78  62 /  10  20  70  40
-- End Changed Discussion --

&&

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

$$

SHORT TERM...KS
AVIATION...Wellington