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000
FXUS64 KMRX 260659
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
259 AM EDT Fri Apr 26 2024

...New SHORT TERM, LONG TERM...

.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...
(06Z TAFS)
Issued at 120 AM EDT Fri Apr 26 2024

Radar and obs show light precip falling from a midlevel cloud deck
in Middle TN, but it appears to not be reaching the ground as it
evaporates in a very dry low layer. This precip is dissipating as
it moves east, and so it should not impact the TAF sites in East
TN. There will be broken to overcast clouds through the morning,
mainly at or above 5 kft. These clouds should become scattered in
the afternoon at TYS and CHA, but remain broken at TRI. Winds may
become gusty at CHA this afternoon as a S-SE flow develops near a
northward-moving warm front.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             78  63  79  61 /  20   0   0   0
Knoxville McGhee Tyson Airport, TN  73  60  79  58 /  20   0   0   0
Oak Ridge, TN                       73  61  79  59 /  20   0   0   0
Tri Cities Airport, TN              69  56  76  55 /  20  20  10   0

&&

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

$$

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