Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

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FXUS64 KMRX 071811

Area Forecast Discussion
National Weather Service Morristown TN
211 PM EDT Wed Jun 7 2023

...New AVIATION...

Issued at 1047 AM EDT Wed Jun 7 2023

Rain currently blankets the northern tier of the CWA this morning
ahead of a front. Rain will spread southward throughout the day.
The Southern Valley will see the lowest chance of rain today.
Temperatures across the area this afternoon will have quite the
spread, with mid to upper 80`s for the Southern Valley and Plateau
to 50`s and 60`s for far NE Tennessee and SW Virginia.

As far as any forecast updates, blended latest guidance to the
inherited forecast to best match any slight changes. Overall,
forecast for today is on track.


(Today and tonight)
Issued at 316 AM EDT Wed Jun 7 2023

Key Messages:

1. Rain showers spread in from north to south through the day,
with slight chance of isolated thunderstorms, as a cold front
moves through the area.

2. Widespread dense fog possible tonight across northeast TN and
southwest VA if skies can clear enough behind the cold front.


Upper level trough that has been over New England for the last
week will dive down into the southeastern U.S. through the short
term. This is due to the polar jet diving southward out of Canada
on the backside of the trough. This will drive a cold front
associated with the low across New England through the eastern
and south eastern U.S. Rain showers are currently ongoing just to
our north in KY, along and ahead of the cold front. These showers
will soon move into southwest VA. The cold front will push south
through our area this afternoon and exit south into GA this
evening. Expect increasing chances of showers, and perhaps an
isolated storm, as the front pushes through the area. Highest POPs
will be along I-40 and northward, with lesser chances of rain
across the southern TN Valley and southwest NC.

Model soundings show very little CAPE through the day, perhaps a
few hundred J/kg of CAPE, thus the reason for only slight chance
thunder. The central TN Valley may see a few tenths of an inch of
rain while northeast TN and southwest VA up to 0.75 inches. Less
than 0.1 inches south of I-40. Breezy afternoon winds possible
from Knoxville down to Chattanooga this afternoon due to deep
mixing and dry air at the surface, ahead of the cold front and rain

Rain showers end this evening behind the cold front. Widespread
dense fog is possible tonight across northeast TN and southwest VA
as skies clear and plenty of surface moisture to work with due to
the expected rainfall today.


(Thursday through Tuesday)
Issued at 316 AM EDT Wed Jun 7 2023

Key Messages:

1. Dry weather expected Thursday until late Saturday. Temperatures
start below normal, but warm each day.

2. Cold front forecast to sweep across the area next week. Good
chance of the entire area seeing measurable rainfall.


By daybreak on Thursday the front will be well off to our south and
the trough will be set up across much of the eastern United States.
Thursday will also be cool with regards to temperatures, similar to
Wednesday with most locations expected to be around 5 degrees below
seasonal normals. While the daytime temperatures are only a few
degrees below normal, under the clear skies the overnight lows are
expected to drop into the 50s or 40s in the early morning hours late
this week. Slow warming trend of daytime temperatures will take
place as we head into the weekend.

Weather pattern begins to change once we move into next week as the
trough/low over the eastern United States finally meanders it`s way
of the east coast. It will quickly be replaced by a low diving south
out of Canada. This will bring with it a strong front early next
week that looks like it should provide widespread showers and
thunderstorms sometime Sunday or Monday. In addition this front will
also knock back temperatures again with highs expected to reach only
into the 70s or low 80s Monday and Tuesday of next week. Still much
up in the air with regards to precipitation timing along this early
week system, so have remained close to the NBM guidance with PoP and
QPF forecasts for Monday and Tuesday of next week.


(18Z TAFS)
Issued at 150 PM EDT Wed Jun 7 2023

Complicated forecast the rest of the day for both TYS and TRI. CHA
however, shouldn`t be impacted by any low CIGs or VSBY. PROB30 was
added at the end of the period for the potential of showers
overnight. TRI appears it will experience the worst conditions
with dense fog and low CIGs possible overnight. Confidence on
onset and just how low these variables will be is honestly low.
Both TYS and TRI will bounce between IFR and MVFR at times. A
tempo for LIFR at TRI has been kept from the 12z TAFs. After 12z
is when we expect conditions to improve to VFR.


Chattanooga Airport, TN             62  82  57  83 /  30  10   0   0
Knoxville McGhee Tyson Airport, TN  58  79  52  81 /  30   0   0   0
Oak Ridge, TN                       56  79  52  82 /  20   0   0   0
Tri Cities Airport, TN              51  73  46  76 /  20   0   0   0




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