854
FXUS64 KMRX 290523
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
123 AM EDT Sat Jun 29 2024

...New AVIATION...

.SHORT TERM...
(Tonight through Sunday)
Issued at 931 PM EDT Fri Jun 28 2024

Isolated to scattered showers in southern sections may linger for
a few more hours in an axis of higher theta-e air. Most of the
showers should dissipate by midnight. Later in the night, the low
level SE flow will spread cloud cover into the southern Valley
areas, while northern and central areas will be mostly clear where
there is a downslope flow. The update will make some adjustments
to PoPs in the first half of the night, and bring temperatures up
a little based on current obs.

&&

.LONG TERM...
(Saturday night through next Friday)
Issued at 227 PM EDT Fri Jun 28 2024

Key Messages:

1. Showers and storms through Sunday.

2. Drying out and warming up Monday through midweek.

3. Ridge breaks down toward the end of the period, giving us more
chances for showers and storms.

Discussion:

A few isolated to scattered showers and storms will likely be
ongoing at the start of the period. Showers and storms should wane
in intensity as we lose our daytime heating. However, a few
lingering showers and storms can be expected through the night due to
zonal flow just ahead of an approaching cold front and weak
divergence aloft.

Showers and storms will increase in coverage on Sunday with the
frontal passage. Peak coverage will occur during the afternoon
hours, when heating is maximized. With weak 0-6km (around 25kts)
shear in place, a few strong storms are possible. However, storm
threat is conditional on how much instability can develop. The
amount of instability is uncertain due to the potential for
lingering cloud cover associated with any ongoing showers/storms
Sunday morning. Overall, the probability of severe weather is very
low. This aligns with the SPC day 3 marginal risk in place.

We dry out on Monday behind the cold front. Monday will be the
nicest day of the long term with near normal temps and lower
dewpoints. Ridging remains in place through Tuesday but with temps
back into the lower 90s. The ridge begins to flatten on Wednesday
which means slight chance to chance POPs for diurnal showers and
storms are back in the forecast. The ridge becomes further
suppressed and pushes deeper to the south on Thursday. This is due
to an incoming, broad, long wave trough from out of the northwest.
This feature will have an associated cold front but it`s too early
for details on timing. In general though, with the trough and cold
front approaching, increased POPs are expected on Thursday and
Friday.

&&

.AVIATION...
(06Z TAFS)
Issued at 100 AM EDT Sat Jun 29 2024

Will generally see scattered to broken clouds around for the
period, but cigs will be mainly VFR. May see some brief MVFR cigs
again at CHA during the early morning hours similar to yesterday,
and will include a tempo MVFR group there again. In addition, we
will see some mainly scattered showers/thunderstorms around mainly
during the afternoon, and will try to time the highest
probability time period with a prob30 thunderstorm group at each
site.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             92  76  93  71 /  40  20  70  10
Knoxville McGhee Tyson Airport, TN  91  75  91  70 /  40  30  80  20
Oak Ridge, TN                       91  74  91  66 /  40  20  70  10
Tri Cities Airport, TN              91  72  88  64 /  40  30  80  30

&&

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

$$

SHORT TERM...DGS
AVIATION...