272
FXUS64 KJAN 051817
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
117 PM CDT Wed Jun 5 2024

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 1155 AM CDT Wed Jun 5 2024

Rest of this afternoon...

Cold pool from early morning storms has settled across the area,
leading to another round of potential reinvigoration of storm
development this afternoon. Water vapor/RAP analysis indicate
another shortwave moving across the ArkLaTex, with increased
ascent & potential organized aftn convection. Regional radars are
quiet, but cooler cloud tops in infrared satellite imagery are
peaking back up across the Gulf Coast in central LA. Convective
allowing models support the idea of another round of aftn storm
development, mainly along & southeast of the Natchez Trace
corridor. This includes portions of northeast Louisiana but a
majority east of the MS River from Adams to Jackson Metro of
Hinds, Rankin, Madison to Leake-Neshoba-Kemper Counties. Morning
modifications to 12Z JAN sounding, using areas in the Pine Belt
where WAA will be the most efficient (i.e. highs near 90 degrees),
indicate potential for scattered microburst potential. With
around 340K 925-850mb Theta E reservoir over the Gulf Coast region
& nosing into the Hwy 84 corridor, this environment should be
able to support another round of increased convective organization.
Another potential north-south orientation of an eastward sweeping
line is possible along the I-20 to Hwy 84 corridors through early
evening. Steep mid-level lapse rates of 7-8 deg C, 29-31C
vertical totals observed this morning, 30kts mean bulk shear &
ongoing 3-4k J/kg ML/MUCAPE along & south of the I-20 corridor
maintain potential for severe storms. Ongoing "Marginal" was
adjusted to expand to include portions of the Natchez Trace
corridor into eastern MS just north of the I-20 corridor. Main
threats remains to be damaging wind gusts & hail up to quarter
size. Updates to severe graphic will be out shortly. Forecast
updates are out. /DC/

&&

.DISCUSSION...
Issued at 344 AM CDT Wed Jun 5 2024

Through tonight: We`re rolling into yet another day of the same
weather pattern with a forecast heavily contingent on the
evolution of mesoscale features. For now, all is quiet in the wake
of yesterday afternoon and early evening`s MCS, with very patchy
transient low clouds early this morning. The next feature of
interest is an MCS pushing through the ArkLaTex. Convection along
the leading edge of this feature has become less vigorous over the
past couple of hours, but for the time being it is still
sustaining a push of quite strong wind with radar velocity
sampling 50-65 kt. Contrary to previous MCSs, this one has a much
greater southward component, likely riding along a corridor of
greater instability that extends from east TX into southwest LA.
As northern portions of this MCS cross over into a more stable
environment and given the lack of deeper convection to maintain
the cold pool, current thinking is these storms will weaken
significantly as they approach our area later this morning, with
healthier convection surviving a more southward path toward the
Gulf. However, remnant outflows and perhaps an MCV from this
system will likely drift eastward into our area later today and
with daytime heating and airmass recovery, may serve as forcing
for new development of convection through the afternoon into the
early evening.

Today`s lower probability but higher ceiling scenario is the cold
pool from this morning`s MCS is stronger than anticipated and either
maintains its current strength or weakens some then reorganizes
later today (similar to yesterday`s system) and moves into parts
of northeast LA and west/south MS. Again, similar to recent days,
damaging wind gusts would be the main concern. A marginal severe
risk is being highlighted in the areas that could be impacted by
this conditional threat. /DL/

Thursday through mid next week...

Storm chances will likely continue into Thursday as a cold front
pushes south. Storms will continue to be possible along and south
of the front where moisture remains abundant, but generally weaker
flow than previous systems will limit organization and thus limit
magnitude of severity. Can`t rule out isolated storms across
southwestern areas Friday as the aforementioned cold front stalls
out in the vicinity of the HWY 84 corridor. Opted to add low end
PoPs in this area to account for this. Lack of airmass change to
the south will keep storm chances in the forecast.

Surface high pressure settles in for much of the area Saturday
and drier air will shift focus further south and west, thus
limiting the chance for storms. As this high pressure shifts east
Sunday, moisture recovers. A shortwave pushes across the midsouth,
increasing rain and storm chances. Increased flow could aid in
organization, but confidence on overall evolution is low as
mesoscale features could play a role.

Early to mid next week a seasonally anomalous trough digs south
across the eastern CONUS. A stalled boundary could shift while
several waves push across the area. Areas to the south of this
boundary, mainly south of I-20, will keep rain and storm chances
at any given time, so activity should continue into next week.
That said, organization appears less likely than seen previously
and should keep severe chances isolated. /SAS/

&&

.AVIATION...
(18Z TAFS)
Issued at 115 PM CDT Wed Jun 5 2024

Another round of SHRA & TSRA possible this afternoon, with 40-50 kt
wind gusts & 1 inch hail possible. Brief categorical reductions will
be possible in storms. Late tonight into early Thursday morning, low
MVFR stratus ceilings will be possible again & patchy fog cannot be
ruled out, especially in the Pine Belt. These ceilings & fog
should lift just after daybreak Thursday. Most SHRA & TSRA migrating
along & southeast of a line from HEZ, PIB-HBG to MEI areas,
especially in the I-59 to Hwy 84 corridors, by daybreak through
midday Thursday. Winds will mainly be southerly & gusty at times
today, gradually shifting more northerly into Thursday aftn. /DC/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       70  88  69  89 /  50  20   0   0
Meridian      69  90  68  90 /  70  40   0   0
Vicksburg     70  90  70  90 /  40  10   0   0
Hattiesburg   72  90  71  93 /  60  60   0  20
Natchez       70  89  69  90 /  50  20   0  20
Greenville    71  91  70  89 /  20   0   0   0
Greenwood     70  90  68  88 /  40  10   0   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&

$$

DC/SAS20/DC