131
FXUS64 KJAN 081825 AAC
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1225 PM CST Wed Jan 8 2025

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 959 AM CST Wed Jan 8 2025

GOES-16 satellite shows has stratus cloud cover in place over the
ArkLaMiss region. As an arctic high lingers over the area, cool/dry
conditions will continue. Skies are expected to gradually clear
throughout the day. Temperatures will remain on the cool side with
afternoon highs are expected to reach the upper 30s near the Delta
region and low/mid 40s elsewhere. However, afternoon highs may be
lower than expected due to cold air advection and stratus clouds
that are slow to dissipate. /SW/

&&

.DISCUSSION...
Issued at 402 AM CST Wed Jan 8 2025

Today through tonight...An extensive area of stratus prevails
across the area early this morning, but expect the clouds to
dissipate through the morning hours. Skies will begin to clear
this afternoon, with highs ranging from the upper 30s across the
Delta, to the upper 40s in the Pine Belt Region. Surface high
pressure ridging will settle in over the area tonight and with
radiational cooling, temperatures will fall into the low to mid
20s across most of the area. A few locations may fall into the
upper teens across the Golden Triangle. /15/

Thursday and Friday: A much anticipated winter storm is
continuing to come into somewhat clearer focus. As a sharp upper
trough pivots across the central CONUS, surface cyclogenesis will
ensue along the northwestern Gulf coast Thursday. The system will
track eastward along the coast into Friday, spreading precip
northward across our area late Thursday into Friday. A seemingly
consistent trend in model guidance is for later arrival of precip
on Thursday, around or after sunset in many areas. Clouds will
increase substantially earlier in the day, though temps are
expected to rise into the 40s across most of the area.

Thursday late afternoon and evening, temps will dip some with the
loss of the insolation, and with wetbulb temps in the 30s, some
additional cooling will occur at precip onset. While surface temp
advection will be quite weak, strong 850 mb warm advection will
occur overnight especially along and south of the I-20 corridor,
resulting in a growing low level warm layer aloft. Forecast low
temps are near or just above freezing over much of the southern
half and near or just below freezing over the northern half. This
should ensure a cold rain over roughly the southern third of the
area. Over the central tier, there may be enough cold air before
the warm layer aloft grows for snow or sleet at the onset of
precip, but it is very likely to transition to cold rain as the
column saturates and low level WAA increases. At this time, any
accumulations appear most likely to be negligible, but there is
still low potential for at least brief travel impacts in these
areas.

Things will be most interesting across our northern tier areas,
where it will be a bit colder at onset and a mostly subfreezing
wetbulb profile implies evap cooling potential at onset. In many of
these areas, 850 mb WAA will be weaker, resulting in thermal
profiles that are more isothermal near the freezing mark as
saturation occurs. This still leaves considerable uncertainty, as
just a few degrees will mean the difference between mostly very
cold rain, a rain/snow mix, and mostly snow. For snow accums,
lower SLRs and any p-type changes will cut in to storm totals.
It`s rather possible there will be snow/sleet accumulations that
are wiped out by a transition to rain. However, if the colder
solution prevails, this is the area with the higher ceiling for
impacts from accumulating snow. As a result, the Winter Storm
Watch has been expanded to include the remainder of the US 82
corridor in our area.

Most areas may transition to rain for a period on Friday morning as
the pocket of warmer 850mb air shifts across the area. However,
with cooling during the afternoon, a transition back to snow is
possible in these areas before precip tapers off by Friday
afternoon or early evening.

Saturday through Tuesday: With the passage of the upper trough axis,
ridging will build in at the surface to end the week with a return
to drier conditions. Another shortwave will graze the region Sunday
into Monday, but that system is looking more dry, with just some
isolated shower chances across our south. Otherwise, conditions will
remain seasonably cool, with Sunday morning being the coldest with
lows in the lower 20s in some areas. /DL/

&&

.AVIATION...
(18Z TAFS)
Issued at 1225 PM CST Wed Jan 8 2025

VFR flight conditions with northerly winds near 10 kts are
expected to prevail through the TAF period. /SW/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       23  48  35  42 /   0   0 100 100
Meridian      20  47  31  41 /   0   0  90 100
Vicksburg     24  46  34  42 /   0  10 100 100
Hattiesburg   24  50  35  47 /   0   0  90 100
Natchez       26  48  36  43 /   0  10 100  90
Greenville    24  40  32  36 /   0  10 100  90
Greenwood     22  45  32  39 /   0   0  90 100

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Winter Storm Watch from Thursday afternoon through Friday
     evening for MSZ018-019-025-026-034.

     Winter Storm Watch from Thursday evening through Friday evening
     for MSZ027>033.

LA...Winter Storm Watch from Thursday afternoon through Friday
     evening for LAZ007.

AR...Winter Storm Watch from Thursday afternoon through Friday
     evening for ARZ074-075.

&&

$$

15/DL/SW