480
FXUS64 KJAN 030027 AAA
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
727 PM CDT Sun Jun 2 2024

...New MESOSCALE UPDATE, AVIATION...

.MESOSCALE UPDATE...
Issued at 709 PM CDT Sun Jun 2 2024

In strong contrast to most deterministic guidance, an MCS has
taken shape and is maintaining itself well as it pushes east
across Northeast Texas as of 7 PM. Additionally, some sea breeze
convection is continuing along a line from Corsicana, TX
southeastward to the Lake Charles, LA area. The air mass north of
the sea breeze and east of the advancing MCS is marked by MLCAPE
of 2000-3000 J/kg and a Lifted Index of -8 to -10. A gradient of
PWAT is aligned parallel to the mid-level flow and deep-layer wind
shear (though flow is modest). Based on radar presentation and
anticipating cold pool dynamics to sustain an east-southeast
momentum for the MCS, have at least increased our POPs around
midnight tonight into the early morning into the "chance" range.
Short-term high-res models are struggling to capture the situation
with any more confidence, but latest few runs of the HRRR seem to
be reasonable with the general idea. As was the case last evening,
the MCS may be choked off of instability or start to compete with
the lingering sea breeze convection as the two areas interact.
That might limit the farther eastward extent, but will continue to
monitor the trends this evening. If storms do reach our area with
some organization, a damaging wind threat and heavy rainfall are
possible especially in northeast/central LA and southwest MS. /NF/

&&

.DISCUSSION...
Issued at 325 PM CDT Sun Jun 2 2024

Monday:

The active weather period will pick back up on Monday as
shower/thunderstorm chances return across the CWA. Another
shortwave disturbance from central TX is expected to push eastward
towards our area. As the shortwave approaches, model guidance is
suggesting that a MCV will approach the ArkLaMiss area in the
afternoon and evening hours and help to initiate storms. With
dewpoints in the 70s, decent instability, and lapse rates, some
storms could be strong to severe. A "Marginal" risk for severe
weather was expanded to include areas west of I-55. High
temperatures in the upper 80s to near 90 degrees are expected.
/SW/

Monday night through Saturday night: An active weather pattern
will continue through most of the upcoming week with perturbed
westerlies having the greatest influence on our forecast. As has
been the case recently, mid level flow will be more than
sufficient for organized convective systems, and moisture/instability
will occasionally support damaging wind and heavy rainfall
threats.

The biggest challenge will be forecasting the timing of any
systems, and it continues to look like the mid to late week time
frame will be the primary focus for a more significant convective
system to impact the area. With the upper level pattern becoming
more northwesterly and cyclonic, a cold front is expected to
approach the area Wednesday as a stronger perturbation crosses
the forecast area. Cold air aloft combined with a hot and humid
boundary layer will provide a favorable environment for strong to
severe convective wind during peak heating, so we`ll be monitoring
for potential convective systems and ramp up the messaging as
confidence increases. It seems late Wed/Thu/early Fri are when
the global models show the strongest convective signals.

Thereafter, guidance is bouncing around a good bit between
different solutions with some showing drier while others keep it
more warm and humid, and perhaps active in terms of convection
into the weekend. /EC/

.AVIATION...
(00Z TAFS)
Issued at 709 PM CDT Sun Jun 2 2024

Confidence on coverage and timing of SHRA or TSRA activity
throughout he period is too low to include in the TAFs at this
time for most sites, however typical seasonal pattern of
increasing chances during the 18Z Monday to 00Z Tuesday time frame
is expected somewhere in the forecast area. Will update TAFs with
timing or impacts as confidence increases. Otherwise, some low
stratus or patchy BR could produce MVFR conditions at a few sites
between the 09Z to 15Z Monday time frame. /NF/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       68  88  71  90 /  10  30  30  30
Meridian      67  89  70  90 /  10  30  20  40
Vicksburg     70  89  73  90 /  20  30  40  20
Hattiesburg   69  90  72  91 /  10  50  40  30
Natchez       69  88  71  90 /  30  50  40  20
Greenville    71  89  74  90 /  10  30  40  20
Greenwood     69  90  73  90 /   0  20  30  30

&&

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

$$

SW/EC/NF