918
FXUS64 KMEG 081653
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1053 AM CST Wed Jan 8 2025

...New AVIATION...

.SYNOPSIS...
Issued at 232 AM CST Wed Jan 8 2025

A significant winter storm will move through the area on Friday,
bringing a broad swath of 4 to 6 inches of snowfall along the
I-40 corridor. A more wintry mix is expected in portions of north
Mississippi. A Winter Storm Watch is in effect from Thursday
evening to Saturday morning for the entire Mid-South.

&&

.DISCUSSION...
(Today through Tuesday)
Issued at 232 AM CST Wed Jan 8 2025

Today`s forecast looks like a carbon copy of yesterday`s, with a
thick stratus deck causing a few flurries and keeping temperatures
in the mid 30s. Winds are still northeasterly and will continue to
put a little bite on the cold air, though nothing headline worthy.

The major attention grabber of this forecast period is the winter
storm incoming on Friday. A large Gulf Low is expected to
materialize along the southeast TX coast Thursday evening. The
surface low is expected to trek across southern and central MS/AL,
keeping the vast majority of our area on the cold, snowy side.
There`s already a very cold airmass in place so precip type is
less of a question mark than it was with the previous weekend`s
system. We`re looking at a very efficient band-like snowfall on
the back side of the surface low starting late Thursday night.

The heaviest snowfall is expected to occur between 6AM and noon on
Friday. Probabilistic guidance is still showing upticks on %
chance of exceeding 4 inches and we`re even seeing an uptick in
the % chance of exceeding 6 inches as well, especially just south
of the I-40 corridor. Digging into the ensemble space, there has
certainly been an upward trend in snow amounts with each
subsequent run since yesterday morning`s forecast. Both the LREF
ensemble mean and its individual components depict a swath of at
least 6" of snow in the Memphis metro along this I-40 corridor
between 12AM Friday and 12AM Saturday. As such, a Winter Storm
Watch has been hoisted for the entire area and will almost
certainly need to be upgraded to a Winter Storm Warning in a later
forecast.

The main uncertainty lies in a potential narrow corridor of a
changeover to liquid precip over north Mississippi on Friday
afternoon. Looking at forecast soundings for our southeastern
zones on Friday, there isn`t an obvious warm nose with a sudden
drop to below freezing at the surface that would make me think
freezing rain; almost the entire column is at or below freezing.
If any locations do see a mix of winter precip, it would likely be
a mix of rain and snow. In addition to the 2-4 inches of snow,
we`re generally not expecting any more than a light glaze of ice
in our Mississippi counties, if that.

Impacts from this system should not be taken lightly. The Winter
Storm Severity Index paints a large area of "major impacts" from
eastern Arkansas through the Memphis metro on Friday. This
entails considerable disruptions to daily life. Driving conditions
will be dangerous or at times, impossible. This is the kind of
heavy snow that can cause widespread closures and disruptions to
infrastructure. Even outside the locations of heaviest snow,
moderate impacts are expected, which still means driving
conditions will be quite hazardous.

After the storm moves out, another cold airmass will quickly slide
in behind it. This will be devastating for travel conditions as
we will barely rise above freezing for several days post heavy
snow, especially given a thick snowpack which usually causes
afternoon temperatures to drastically underperform. Any snow left
untreated on residential roads will further compact into an icy
mess for many days after the snowfall has ended. Start making
contingency plans for this weekend. If this snowfall lives up to
its potential (which it`s looking like it will), you will not want
to be out driving. Bitter cold overnight "feels like"
temperatures in the low 20s are expected through at least mid next
week. Little to no relief from the cold is in sight for the next 7
days.

CAD

&&

.AVIATION...
(18Z TAFS)
Issued at 1050 AM CST Wed Jan 8 2025

VFR. Winds 5kt or less will veer southeast over the next 24-30
hours. Mid-level clouds should overspread the Midsouth late
tomorrow ahead of a significant Winter storm. Winter weather
impacts should begin Thursday night.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Winter Storm Watch from Thursday evening through late Friday
     night for ARZ009-018-026>028-035-036-048-049-058.

MO...Winter Storm Watch from Thursday evening through late Friday
     night for MOZ113-115.

MS...Winter Storm Watch from Thursday evening through late Friday
     night for MSZ001>017-020>024.

TN...Winter Storm Watch from Thursday evening through late Friday
     night for TNZ001>004-019>022-048>055-088>092.

&&

$$

PUBLIC FORECAST...JDS
AVIATION...SJM