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000
FXUS64 KMRX 230107
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
907 PM EDT Mon Apr 22 2024

...New UPDATE...

.UPDATE...
Issued at 905 PM EDT Mon Apr 22 2024

The forecast for tonight generally looks to be on track, with a
chilly and mostly clear night on tap. The frost advisory still
looks reasonable as is. Will just make a few tweaks to temps and
dew points with this update.

&&

.SHORT TERM...
(This evening through Tuesday)
Issued at 320 PM EDT Mon Apr 22 2024

Key Messages:

1. Frost development is expected again tonight in most of the same
areas as last night. Patchy frost is still possible elsewhere.

2. Tuesday will be milder and drier with breezy southerly to
southwesterly wind.

This Evening/Tonight

Currently this afternoon, shortwave troughing has shifted off to our
east with high pressure gradually approaching from the west.
Tonight, high pressure will become centered directly over the area,
which will lead to another night of subsidence and radiational
cooling after some WAA today. As such, frost development is expected
in most of the same places as last night but may not be as
widespread if winds remain in certain areas. With these
considerations, another frost advisory was sent out for most of the
same areas minus the southern Plateau based on better WAA this past
afternoon. Patchy development is still possible there and in other
locations.

Tuesday

For Tuesday, another shortwave/system will be noted to the north
with high pressure shifting further to our southeast. Recent height
rises and a more southerly wind will promote milder conditions
compared to today. Also, the increasing MSLP gradient and 850mb flow
of 25 kts or more will make for a breezier day. Efficient mixing is
also expected with the additional heating and will make for RH`s
dropping into the 20s. Fire weather will be a focus during the day
tomorrow, but luckily a lot of vegetation has returned. The only
additional messaging will be focused in the FWF for now.

&&

.LONG TERM...
(Tuesday night through next Monday)
Issued at 320 PM EDT Mon Apr 22 2024

Key Messages:

1. Low-end rain chances Tuesday night into Wednesday.

2. Temperatures becoming above normal with breezy conditions late
week and into the weekend, and possibly returning rain chances.

Discussion:

Tuesday night into Wednesday just might be our best chance for rain
as a front tries to push through the Ohio Valley into the Tennessee
Valley as a shortwave helps it move through the region. This system
will be fighting it`s way into a area of high pressure at the same
time that the synoptic level forcing slides eastwards into the
northeastern United States. This means that the precipitation along
the front should begin to fizzle out as it moves towards the
southern Appalachian region. Best precipitation chances will be in
northeast TN, southwest VA, and along the southern Appalachian
mountains where they`ll get some orographically enhanced forcing.

Once this system moves south of the area it will likely stall out
somewhere along the Gulf Coast states leading to fairly mild
conditions over our area with a slow warming trend the rest of the
work week, with temperatures back in the 80`s be the end of the
weekend.

Still some uncertainty with shower and thunderstorm chances as we
head into the weekend, but besides Wednesday, this will likely be
our next chance for rain for the 7-day forecast. A strong low
pressure system looks to eject out through the northern plains into
the Great Lakes region. This could induce a weak warm front through
the southeast US, but better precipitation chances would be along
the cold front associated with this system. As of right now most
deterministic and probabilistic guidance is keeping the front and
associated precipitation to our west in western KY/TN... However we
could see some storms move into the eastern TN valley, or very
possibly the front makes it further east and we get more widespread
storms. Will continue with low end precipitation chances in the
forecast to give people a heads up about potential storms next
weekend, and will monitor for trends on the movement of the low
pressure system.

&&

.AVIATION...
(00Z TAFS)
Issued at 630 PM EDT Mon Apr 22 2024

VFR conditions are expected for the period all sites. Winds will
be light overnight, then become south to southwest around 10-15 kts
with some higher gusts by afternoon.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             42  75  53  75 /   0   0  10   0
Knoxville McGhee Tyson Airport, TN  37  73  54  72 /   0   0  20  10
Oak Ridge, TN                       37  73  53  74 /   0   0  30  10
Tri Cities Airport, TN              34  70  50  67 /   0   0  40  20

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...Frost Advisory from 4 AM to 9 AM EDT Tuesday for Cherokee-Clay.

TN...Frost Advisory from 4 AM to 9 AM EDT Tuesday for Blount Smoky
     Mountains-Campbell-Claiborne-Cocke Smoky Mountains-East
     Polk-Hancock-Hawkins-Johnson-Morgan-Northwest Carter-
     Northwest Cocke-Northwest Greene-Scott TN-Sevier Smoky
     Mountains-Southeast Carter-Southeast Greene-Southeast
     Monroe-Sullivan-Unicoi-Washington TN.

VA...Frost Advisory from 4 AM to 9 AM EDT Tuesday for Lee-Russell-
     Scott VA-Washington VA-Wise.

&&

$$

SHORT TERM...BW
AVIATION...