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000
FXUS64 KMRX 220530
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
130 AM EDT Mon Apr 22 2024

...New AVIATION...

.UPDATE...
Issued at 943 PM EDT Sun Apr 21 2024

No changes to make note of for the tonight period. Still expecting
the same outlined below, therefore the forecast is on track.

Isolated gusty winds this evening will subside overnight as
surface high pressure builds in. Once that occurs and skies clear,
expect boundary layer decoupling. Frost Advisory still in effect
for some locations from 2 to 9 AM EDT Monday morning.

KS

&&

.SHORT TERM...
(This evening through Monday)
Issued at 235 PM EDT Sun Apr 21 2024

Key Messages:

1. Frost is expected across much of the area tonight and early
Monday morning. Please refer to the frost advisory product for
more information.

2. Low afternoon relative humidity for Monday with values in the
20s.

Discussion:

For the remainder of the afternoon into the evening, sprinkles
will end across the far east Tennessee mountains and southwest
North Carolina. Satellite and surface observations show cloud
cover diminishing across the Plateau counties. This trend will
continue across the rest of the area this evening.

For tonight, sky becoming mostly clear with surface ridge building
into the region allowing winds to subside. Calm to light winds
across expected over much of the area overnight except for the
higher elevations. Clear sky, calm winds, and dry airmass will
temperatures to drop into the 30s over much of the area with
patchy to areas of frost developing. A frost advisory has been
issued over parts of the area.

For Monday, building upper ridge and surface ridging will produce
a sunny day with light winds. Plenty of sunshine and dry airmass
will allow temperature to warm nicely after a chilly start. Main
concern is the low afternoon relative humidity with values in the
20s.

&&

.LONG TERM...
(Monday night through next Sunday)
Issued at 235 PM EDT Sun Apr 21 2024

Key Messages:

1. Patchy frost is possible again on Tuesday morning, especially in
the same locations as tonight.

2. Light rain is possible on Wednesday, focused further north.

3. Late in the week and through the weekend, breezy southerly winds
and a warming trend are expected, along with low-end chances for
showers and thunderstorms.

Monday Night through Thursday

At the start of the period, troughing will be to our east with high
pressure centered over the area. Subsidence and light winds will
allow for radiational cooling and another seasonally cold night.
Recent WAA may inhibit temperatures from being as cold as tonight,
but conditions are certainly still favorable for frost development
into Tuesday morning in the same locations. With the current frost
products out, no additional messaging will be utilized. On Tuesday,
high pressure will shift off to the east, leading to more southerly
flow. A dry and milder day can be expected with southerly flow and
height rises. Also during this time, a shortwave will be moving into
the Upper Great Lakes with a frontal boundary extending southwest at
the surface.

Tuesday night into Wednesday, the shortwave will progress southward
with the frontal boundary moving southward from the Ohio River
Valley. During this time, rain chances will return to the area,
focused further north closer to better forcing. Moisture and
coverage of showers will be very limited overall, especially further
south. Wednesday night to Thursday, the front will weaken and become
fairly stationary over the area with high pressure expanding from
the north. Depending on how much moisture remains in southern
portions of the area, rain activity may move in at some point on
Thursday, but these chances are very limited at this point. A deeper
trough will come into focus over the Rockies.

Friday through Sunday

Late in the week, the aforementioned trough will eject into the
central U.S. with strong cyclogenesis expected by Friday morning.
The trough will become more negatively tilted with the surface low
deepening to near 990mb over Kansas. For our area, broad, strong
southerly flow can be expected on Friday as the system moves towards
the Great Lakes. The latest indications are for the cold front to
remain pretty far to our west with another area of low pressure
developing later in the weekend. Based on this pattern, rain chances
will be pretty limited in our area with the more organized
strong/severe convection remaining well to our northwest. The
consistent southerly flow will produce breezy conditions in the
mountains and a continual rise in temperatures to above normal.

&&

.AVIATION...
(06Z TAFS)
Issued at 130 AM EDT Mon Apr 22 2024

VFR conditions through the period with light northerly winds.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             66  42  74  52 /   0   0   0  10
Knoxville McGhee Tyson Airport, TN  64  39  71  53 /   0   0   0  20
Oak Ridge, TN                       66  39  72  52 /   0   0   0  20
Tri Cities Airport, TN              61  36  69  50 /   0   0   0  30

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...Frost Advisory until 9 AM EDT this morning for Cherokee-Clay.

TN...Frost Advisory until 9 AM EDT /8 AM CDT/ this morning for
     Bledsoe-Blount Smoky Mountains-Campbell-Claiborne-Cocke
     Smoky Mountains-East Polk-Hancock-Hawkins-Johnson-Morgan-
     Northwest Carter-Northwest Cocke-Northwest Greene-Scott TN-
     Sequatchie-Sevier Smoky Mountains-Southeast Carter-
     Southeast Greene-Southeast Monroe-Sullivan-Unicoi-
     Washington TN.

VA...Frost Advisory until 9 AM EDT this morning for Lee-Russell-Scott
     VA-Washington VA-Wise.

&&

$$

SHORT TERM...DH
LONG TERM....BW
AVIATION...