396
FXUS64 KMRX 261744
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
144 PM EDT Fri Apr 26 2024

...New AVIATION...

.UPDATE...
Issued at 1105 AM EDT Fri Apr 26 2024

Only minor tweaks to the immediate forecast to match up with
current conditions and trends.

A few hundredths to a couple tenths of an inch of rain has fallen
from around Dayton, TN north to Scott County, TN with precip not
recorded NE of Knox County just yet. Expect this trend to continue
with just light showers/drizzle and no threat for lightning. This
activity will move north and east over the area exiting out of
Southwest VA tonight.

Wind gusts nearing 40 mph are currently occurring at the wind
favored locations such as, Cove Mountain and Camp Creek. Not
expecting gusts to exceed this as mesoanalysis only shows 25 KT
at 850 over the mountains. Still continuing with the previous
forecasts thoughts as far as electing not to go with a Wind
Advisory anywhere.

KS

&&

.SHORT TERM...
(Today and tonight)
Issued at 248 AM EDT Fri Apr 26 2024

Key Messages:

1. Mostly cloudy this morning with partial clearing in the
afternoon; light rain possible in a few areas.

2. Breezy in the mountains tonight.

Discussion:

A surface warm front is located south of the area, across central AL
and MS. Light precip on radar in Middle and West TN is associated
with midlevel isentropic lift. The 00Z BNA sounding shows a very dry
air mass below 700 mb, and most of the precip falling into this dry
layer is not reaching the ground, with few surface obs showing rain
east of the MS River. There is also a dissipating trend as it moves
eastward. Models show a few hundredths to a tenth of an inch of QPF
this morning in the Plateau and southern/central Valley, but this
seems overdone given the radar trends. A low to slight chance PoP
will be forecast today across the area, from southern sections this
morning to northern sections this afternoon as the isentropic lift
spreads northeast. Broken to overcast cloud cover should also spread
NE, with southern sections becoming scattered in the afternoon. This
should allow for enough surface heating to bring temperatures into
the upper 70s south, but persistent cloud cover will hold temps in
northern sections in the 60s. A 20-30 kt S-SW 850 mb wind tonight
may create some breezy conditions in the mountains, but likely not
enough for a Wind Advisory at this time. Mid and high clouds will
increase again overnight as the mid/upper level ridge axis moves
east of the area.

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 248 AM EDT Fri Apr 26 2024

Key Messages:

1. Breezy southwest winds Saturday. Could need an advisory higher
elevations, Otherwise, dry and warm conditions is expected through
the weekend.

2. A chance of showers and thunderstorms returns Monday night and
continues through next week. Warm days and mild nights throughout
the rest of the forecast period

Discussion:

In the upper levels, a ridge continues over the Eastern U.S. states
and strengthens through the weekend. While at the surface, a couple
of deep lows move through the Great Plains and Midwest with closed
upper lows. The cold fronts remain to the west of the Mississippi
River and Tennessee Valley through Monday.

Saturday and Sunday stay dry as the cold front from the first system
stalls and weakens near the Mississippi River. Ridging aloft and
high pressure will stay strong over the Southeast. Breezy southerly
winds will continue Saturday. Gusts could reach advisory criteria
for part of the day Saturday in the higher elevations and foothills
of the East Tennessee Mountains with a wind direction that could
enhance downslope winds. Elsewhere, wind gusts will likely top out
around 30 mph mainly the Southern Tennessee Valley and Cumberland
Plateau.

Monday and Tuesday, a surface low will move through the Great Lakes
and into Canada. The front should get held up to the NW and may not
be a clean frontal passage for our area. However a shortwave will
help bring showers and storms to the region overnight Monday night
and Tuesday. Severe potential still looks low at the moment but will
continue to monitor this systems development. Wednesday and Thursday
the ridge stays strong but more impulses moving through the
southwest flow aloft should trigger more widely scattered to
scattered afternoon and evening showers and storms to form. Rainfall
amounts Tuesday through Thursday right now don`t look that
impressive but stay tuned. The best chance for storms will be
afternoon and evening hours Tuesday through Thursday.

&&

.AVIATION...
(18Z TAFS)
Issued at 133 PM EDT Fri Apr 26 2024

A band of light showers currently exists between approximately
TYS NE to TRI. Expect this to continue to lift north and east
through this evening. TYS should be out of the showery regime in
the next couple of hours followed by TRI, which has a TEMPO to
reflect possible VSBY reduction and BR. Besides maybe short-lived
periods of MVFR with showers, all terminals expected to be VFR.
BKN decks will be up and down the next 24 hours, otherwise, still
expected to remain within VFR. CHA forecast to have SE winds and
gusts near 20 KT the rest of the period, but will continue to
monitor as they have not started there yet possibly due to delayed
mixing with the slow moving warm front.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             63  79  61  83 /   0   0   0   0
Knoxville McGhee Tyson Airport, TN  60  79  58  83 /   0   0   0   0
Oak Ridge, TN                       61  79  59  83 /   0   0   0   0
Tri Cities Airport, TN              56  76  55  81 /  20  10   0  10

&&

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

$$

SHORT TERM...DGS
LONG TERM....TD
AVIATION...KS