791
FXUS64 KLIX 240829
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
329 AM CDT Tue Sep 24 2024

...NEW SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
(Today through Wednesday)
Issued at 233 AM CDT Tue Sep 24 2024

A cold front currently resides basically from Texarkana northeast
to the MO Bootheal this morning. This feature will continue to
move closer to our region today as the parent upper level trough
continues to spread eastward across the lower MS River Valley.
This feature may be enough to produce some isolated to scattered
shower activity across interior south Mississippi and perhaps over
the Florida Parishes of Louisiana. However, QPF signal is modest
given the upper level dry air. In fact, the special 06z sounding
tonight showed this dry column very well...which again should
limit a more widespread shower/storm potential today. The only
other entity to mention this morning is perhaps some patchy fog
in the lower spots, however, guidance may still be a bit too
bullish with fog potential (as we`ve seen recently). The front is
still just far enough away to limit low level moisture pooling,
but there could be some localized patchy fog in those favored
lower elevation spots.

Prior to the front arrival and eventual passage sometime on
Wednesday, we`ll still have to deal with above average
temperatures across the region. Otherwise, for the remainder of
the short term period eyes will shift to two primary synoptic
features...1) the deepening upper level low across the
Cornbelt...which eventually starts heading southward down the
Mississippi River on Wednesday and 2) PTC9 over the western
Caribbean and the impacts the upper level trough and closed ULL
have on it. More about the evolution of those both in the long
term sections. (Frye)

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 233 AM CDT Tue Sep 24 2024

As PTC9 (forecast by this time to be a strong TS or hurricane)
moves northward toward the Panhandle of Florida (quickly I may
add) the 568dam H5 low will center over Arkansas. This will then
take the TC north and eventually perhaps northwestward once it
reaches the ENE or NE periphery of the ULL well inland. Being
removed from the TC there will be a good bit of subsidence on the
far outer periphery, which calls into question any POPs for this
timeframe. At this juncture, decided to continue the ongoing
forecast with consensus models, however, the QPF will contain a
tight gradient if not from the subsidence surrounding the TC, from
the dry slot the develops south of the cold core ULL over LZK or
perhaps the ArkLaMiss region.

Going into the weekend was a bit concerned about the cold
temperatures aloft and any potential convection. With H5 temps
approaching -20C across interior south Mississippi...any robust
updraft could cause some hail potential. However, the QPF signal
doesn`t support this neither does the remaining dry air residing
over the forecast area. Decided to drop the prior 20 percent POPs
respectively and went with a mostly dry weekend with comfortable
mornings and around average or maybe a degree or two shy of
average MaxTs. (Frye)

&&

.AVIATION...
(06Z TAFS)
Issued at 1142 PM CDT Mon Sep 23 2024

VFR conditions in place this evening, and likely to be for much of
the forecast period. Frontal boundary remains to the northwest of
Louisiana. Potential does exist for patchy fog development around
sunrise Tuesday, but only areas that I feel any confidence in
mentioning are at KMCB and KHUM, and will mention brief MVFR to
IFR visibilities there. If any fog does develop, it`ll improve
quickly by mid morning. Only last day of only scattered cumulus on
Tuesday before the front approaches overnight Tuesday night into
Wednesday. Not expecting much in the way of convection prior to
sunrise Wednesday, so there won`t be any mention in this package.
(RW)

&&

.MARINE...
Issued at 233 AM CDT Tue Sep 24 2024

Mainly favorable marine conditions will give way to hazardous
marine conditions by Wednesday as seas begin to build in response
to PTC9 (then likely a TC) moving northward from the western
portions of the Caribbean and southern Gulf of Mexico.
Additionally, despite the building seas, gradient winds will also
increase, which outside of wave heights, wind will also be the
cause for SCAs for the Gulf Waters. Cautionary headlines for the
tidal lakes look also possible respectively. By Friday, the storm
will have moved well inland over Georgia...or points well east of
our region. Seas will begin to relax then and especially going
into the upcoming weekend. (Frye)

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  90  69  84  64 /  20  40  50  20
BTR  94  74  90  68 /  10  30  40  10
ASD  91  72  89  69 /   0  10  40  30
MSY  90  74  88  72 /   0   0  30  20
GPT  88  72  88  70 /   0   0  50  50
PQL  93  72  91  71 /   0   0  60  60

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&

$$

SHORT TERM...RDF
LONG TERM....RDF
AVIATION...RW
MARINE...RDF