223
FXUS64 KMRX 081125
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
625 AM EST Fri Nov 8 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 215 AM EST Fri Nov 8 2024

Key Messages:

1. Some patchy fog is possible in the morning hours.

2. Skies clearing by this afternoon with a drier but still mild
air mass building in.

Discussion:

A cold front is currently moving through the region. Winds have
already shifted but the lower dew points are lagging behind,
currently over Middle Tennessee and Central Kentucky. Patchy fog
is possible this morning before the drier air moves in. Skies will
be mostly sunny by this afternoon. Rain chances will be near zero
as high pressure builds into the Ohio Valley. In the upper
levels, ridging continues over the Southeast.

I blended in NBM 10th percentile for dew points this afternoon
with good mixing likely after the clouds clear out. Highs will be
a bit cooler than yesterday in the lower to mid 70s in most
locations with light northerly winds behind the cold front.

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 215 AM EST Fri Nov 8 2024

Key Messages:

1. Warm temperature remain in place through the middle of next week.

2. Best chances for widespread rain over the weekend into early next
week.

Discussion:

Heading into Saturday we`ll still be sitting under the mid level
ridge, but a slow moving front will be making it`s way across the
Ohio and Tennesee Valleys and eventually move into the eastern
Tennesee Valley over the weekend. Models are starting to hone in on
the leading edge of the precipitation along the front moving onto
the Cumberland Plateau late Saturday and into early Sunday. It will
then slowly spread eastward throughout Sunday. Front struggles to
keep it`s eastward momentum once it gets over the Appalachian
mountains and if it gets hung up in our vicinity we could see an
extra round of precipitation on Monday. But eventually the front
gets a reinforcing shove from a fast moving shortwave zipping
through the Ohio Vally early in the week. Probabilistic guidance has
started to center around the storm total QPF amounts ranging from
around 0.50" to 1.50" from Saturday through Monday. The highest
amounts will likely be along the Cumberland Plateau and upslope side
of the Appalachian Mountains... and the lower amounts in the eastern
half of the TN valley. Assuming the QPF portion of the forecast
verifies, this will likely be the most precipitation we`ve seen
since Hurricane Helene impacted the area in late September.
Obviously we`re not expecting nearly as much rain nor flooding
impacts from this round of showers and storms.

Behind the front the temperatures will dip a bit, but are still
expected to remain above seasonal normals for the first half of the
work week. It will however feel less humid as the drier air from the
west/northwest funnels into the region behind the front.

A more potent system is expected the second half of next week as a
negatively tilted trough blasts through the region. This system
looks to bring another (but shorter duration) round of showers  to
our area, and a much more dramatic cooldown on the backside of the
system as we head towards the weekend. Temperatures look to finally
dip below seasonal normals for Thursday/Friday after the
trough/front swings through.

&&

.AVIATION...
(12Z TAFS)
Issued at 624 AM EST Fri Nov 8 2024

MVFR CIGs are widespread this morning. Fog is very patchy and not
affecting any of the terminals currently. CIGs will lift by mid
to late morning. Northerly winds will be light.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             78  58  75  58 /   0   0  20  30
Knoxville McGhee Tyson Airport, TN  75  52  74  57 /   0   0  10  40
Oak Ridge, TN                       75  52  72  56 /   0   0  10  50
Tri Cities Airport, TN              72  45  73  51 /   0   0   0  30

&&

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

$$

SHORT TERM...McD
AVIATION...McD