368
FXUS64 KMRX 282328 AAA
AFDMRX

Area Forecast Discussion...UPDATED
National Weather Service Morristown TN
728 PM EDT Fri Jun 28 2024

...New AVIATION...

.SHORT TERM...
(This evening through Saturday)
Issued at 227 PM EDT Fri Jun 28 2024

Key Messages:

1. Scattered showers and thunderstorms will be possible Saturday.

2. Above normal temperatures and muggy.

Discussion:

Low level moisture will continue to overspread the area. This
afternoon dewpoints were in the upper 60s to lower 70s. Little
change expected overnight and temperatures will slowly drop to the
mid and lower 70s by sunrise.

With the soupy conditions, a few more showers and thunderstorms can
be expected on Saturday especially over the eastern mountain terrain
including southwest North Carolina. The typical summer-time
scattered nature of these storms will have the capability of
producing locally heavy rainfall and some areas will experience no
rain. Stay patient because those that are dry on Saturday may get
some relief Saturday night into Sunday. Daytime temperatures will be
hot and heat index values will be close to 100 degrees in the
extreme southern Tennessee Valley.

&&

.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...
(00Z TAFS)
Issued at 726 PM EDT Fri Jun 28 2024

Scattered to broken VFR cigs can be expected through the night and
most of tomorrow. Scattered showers and thunderstorms may develop
tomorrow afternoon, so a PROB30 will be mentioned at all sites for
this possibility. Winds will remain under 10 kt through this
period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             93  76  92  76 /  20  20  60  30
Knoxville McGhee Tyson Airport, TN  92  75  91  75 /  20  10  60  40
Oak Ridge, TN                       92  73  91  74 /  20  10  60  40
Tri Cities Airport, TN              90  71  91  72 /  20  10  60  60

&&

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

$$

SHORT TERM...
AVIATION...DGS