497
FXUS64 KMEG 250819
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
319 AM CDT Wed Sep 25 2024

...New SYNOPSIS, DISCUSSION...

.SYNOPSIS...
Issued at 319 AM CDT Wed Sep 25 2024

Unsettled weather will prevail for most of the forecast period as an
upper level disturbance and Hurricane Helene interact late this
week. Heavy rainfall and gusty winds will arrive Friday. Below
normal temperatures and above normal precipitation will continue
until early next week when a pattern change looks to arrive
Monday.

&&

.DISCUSSION...
(Today through Tuesday)
Issued at 319 AM CDT Wed Sep 25 2024

Surface analysis depicts a cold front near Savannah, TN and
stretched through Tupelo MS at this hour. Following quickly behind
is a deep upper level low currently churning near Kansas City, MO.
Associated with this low is another batch of showers pushing into
eastern Arkansas. Diurnally driven thunderstorms are possible this
afternoon due to this disturbance passing through. Skies will clear
out tonight and drop morning lows into the mid 50s and low 60s. Fog
development is possible under clear skies, light winds, and a rain
cooled surface.

This cutoff low will slowly position itself over the Mid-South to
keep unsettled weather around Thursday. Concurrently, Hurricane
Helene will make landfall in the Panhandle/Big Bend areas of
Florida. Helene will then make a sharp left across middle Tennessee
and bring additional rainfall to the area. West Tennessee, the
Missouri Bootheel, and northeast Arkansas have the highest
probabilities (30-50%) to receive 2" or more Friday morning through
Saturday morning. The heaviest of rainfall will be on Friday.
Thankfully, the Mid-South will remain on the left side of the system
and tropical tornadoes are not expected. Winds will be a bit
elevated (15-20mph sustained and gusting to around 30mph), however,
heavy rainfall is currently the primary threat. A Flood Watch is
likely to be issued for the aforementioned area with a chance for a
portion of north Mississippi as well.

The short lived tropical rain is due to Helene`s interaction with
the cutoff low. Guidance has been fairly consistent with the
Fujiwara effect as these two systems interact. Helene will
eventually lift towards the Ohio Valley and leave light to moderate
showers on Saturday. A few light/drizzle showers are possible on
Sunday as the systems continue to influence the region on their exit
paths.

A pattern change will arrive Monday evening as we finally dry out
and high pressure builds. With October kicking off on Tuesday, the
Climate Prediction Center has equal chances for above or below
normal temperatures and leaning below normal chances for
precipitation outlooked for next month.

DNM

&&

.AVIATION...
(06Z TAFS)
Issued at 1125 PM CDT Tue Sep 24 2024

Cut off upper-level low expected to drop into the Lower
Mississippi on Wednesday. Patchy fog may develop at MKL overnight
and produce temporary MVFR conditions at MKL. Otherwise, VFR
conditions should prevail through the period at all sites. VCSH
possible at sites beginning late tonight and continuing into
Wednesday. Potential for VCTS may exist mid to late Wednesday
afternoon. However, confidence in coverage remains to low to
include in the 6Z TAF set. Light N/NNE winds through the period.

&&

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

$$

PUBLIC FORECAST...DNM
AVIATION...CJC