429
FXUS64 KMRX 290135 AAA
AFDMRX

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

...New SHORT TERM...

.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...
(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  40  60  30
Knoxville McGhee Tyson Airport, TN  92  75  91  75 /  20  20  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...DGS
AVIATION...DGS