104
FXUS64 KMEG 231830 AAA
AFDMEG

Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
130 PM CDT Mon Sep 23 2024

...New AVIATION...

.SYNOPSIS...
Issued at 414 AM CDT Mon Sep 23 2024

Unsettled weather will begin this afternoon as a cold front moves
into the region. A few strong thunderstorms are possible this
evening with gusty winds and hail. An upper level low pressure
system will remain over the Mid-South through late week and
result in multiple rounds of showers and thunderstorms. Each day
will feature below normal temperatures with medium to high chances
for rain.

&&

.DISCUSSION...
(Today through Sunday)
Issued at 414 AM CDT Mon Sep 23 2024

The latest surface analysis places a 1012mb low over western
Arkansas with a cold front extending southwest through central
Texas. Aloft, a positively-tilted trough is churning over
Nebraska. A leading weak perturbation, embedded in southwest flow,
is translating through central Arkansas at this hour. A few light
showers are noted on radar, mainly along the Tennessee and
Kentucky border.

The aforementioned trough will slowly deepen and phase with a
northern stream shortwave through Tuesday. Appreciable height
falls will occur late this afternoon and into the evening and
spawn scattered showers and thunderstorms mainly along and north
of I-40. A few of the storms could be strong to severe with
damaging winds and large hail as the main threats. The threat
window will remain limited to late afternoon through early
evening, as instability will wane quickly.

The trailing cold front will slowly cross the Mississippi River
on Tuesday morning. Ahead of the front, instability will increase
to around 2000 J/kg, mainly across portions of west Tennessee and
north Mississippi. A few strong to severe storms will be possible
along and slightly ahead of the front Tuesday afternoon before it
crosses the Tennessee River late Tuesday night. Gusty winds
appear to be the main threat as mid level lapse rates are rather
poor around 6 C/km.

The front will become orphaned just to our east by Wednesday
afternoon as the parent low lifts into Quebec. Cloudy conditions
and cooler temperatures will persist across the region as an upper
low moves overhead and stalls.

Scattered showers and thunderstorms will remain over the Mid-
South Thursday and into the weekend as the upper low interacts
with a tropical system coming north out of the Gulf of Mexico.
The track and intensity of the tropical system still remains a bit
uncertain, however, a good signal for heavy rainfall is
materializing. The latest WPC 5 day QPF shows a range of 3 to 5
inches across much of the Mid-South. The pattern looks to remain
unsettled through the long range forecast as the upper low remains
stalled over the region.

AC3

&&

.AVIATION...
(18Z TAFS)
Issued at 130 PM CDT Mon Sep 23 2024

Primary concern is TS chances through Tuesday afternoon. At this
time, it appears than mid and high level clouds will limit instability
and thunderstorms chances this afternoon. Will continue to monitor
cloud tops for ice accretion and TS potential through the
afternoon.

JBR could see some TS this evening, near the southern extent of
greater TS coverage over MO. This convection will be driven by a
midlevel trough passage forcing the issue. Given limited instability,
MEM may be a little too far removed from this forcing to support
overnight TSRA. 18Z TAF continued the PROB30 TSRA after 04Z for
continuity. This may be removed in future updates.

PWB

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&

$$

PUBLIC FORECAST...AC3
AVIATION...PWB