849
FXUS64 KLIX 301133
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
533 AM CST Sun Nov 30 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 518 AM CST Sun Nov 30 2025

 - A front will sweep across the area today, bringing periods of
   showers mainly this morning, with best chances along/west of
   I-55. Showers steadily dissipate to the east this afternoon.

 - This front stalls in the northern Gulf, then a developing
   surface low on this front drifts northeast bringing more
   widespread showers to the area Monday afternoon & night.
   Rainfall totals of 1-2 inches is expected, with locally higher
   amounts.

 - This system departs early Tuesday, with much colder air
   filtering into the region. Another freeze is likely for areas
   along/north of I-10/12 Wednesday morning.

&&

.SHORT TERM...
(Tonight through Tuesday)
Issued at 1031 PM CST Sat Nov 29 2025

Starting things off with what`s going on outside the front door
tonight, KHDC radar continues to show light echoes/returns across
SE MS. Earlier today, this activity helped to produce a few areas
of light rain and drizzle across SW MS/Florida parishes in
association with a patch of H7 mid-level and subtle PVA along
progressive/quasi-zontal mid-level flow aloft. 00Z KLIX RAOB
illustrates this moist layer well, sandwiched between two
relatively strong subsidence inversions.

Zooming out a bit to get a grand view of the current situation
shows a cold front approaching the area to our northwest. This is
associated with a bigger weather maker up north causing snow for
the Midwest. Expecting to see steady low-level moistening persist
ahead of this frontal boundary as indicated by SE winds helping
to pull (some) moisture north, just not alot as the residual
airmass over the northern Gulf was left from the continental polar
airmass that settled behind our last front, which has since only
modified slightly over Gulf waters with dewpoints in the 50`s to
approaching 60. Still, enough frontogenetic lift in association
with this modest available moisture will support a band of showers
to approach the area from the west around daybreak, as just about
all CAM`s continue to suggest. Not expecting a major impact out
of this, but will be enough to modify the column over time
(starting out as Virga, then evaporative cooling will get any
elevated echoes we`ll see on radar to the ground with time). But
it`ll eventually lose the battle against the dry air later today
and should see showers dissipate with time going into the
afternoon. Still one of those days off/on light showers/drizzle
can be expected, but not anticipating any impacts out of this.

Otherwise, the front will slow to a crawl over the northern Gulf
and becomes more in alignment with low/mid- level quasi-zonal
flow, basically losing it`s push as the parent low exits into the
NE US. Did target a lower approach at highs today given
increasing cloud cover. Am aware the front`s speed will determine
which areas may top out more mild versus northern/northwestern
areas that`ll see the frontal passage earlier, halting
temperatures from climbing much from the lows this morning. But
regardless of the front`s speed, clouds will slow temperatures
from warming too much but could still top in the 60`s to low 70`s
along coastal SE LA and MS, but did drop this down some from the
deterministic NBM. We`ll see if this was a good approach.

We`ll reach a brief period of dry weather Sunday night into
Monday, however will remain cloudy as moisture continues to ride
over the front advecting from the WSW over the Mexican plateau.
Post frontal air will try to settle in making it chilly overall,
with lows in the 40`s to 50`s daybreak Monday.

It`ll be during the day on Monday when we`ll be monitoring low-
genesis along the remnant stalled boundary over the W or NW Gulf,
providing our next round of more widespread showers to the
region. For now, most of Monday morning should be mainly dry but
that`ll quickly change going into the afternoon/evening hours as a
rain shield builds in from the southwest over time. Now, the
details associated with this low get`s pretty interesting in this
time frame, and all is highly reliant on just how "strong/deep"
this low becomes. As the low approaches the area, likely somewhere
either inland SE LA/coastal MS or just offshore, we`ll see the
greatest/maximized 300k moisture transport blossom across coastal
marine waters, accelerating north into coastal MS/AL indicating
the strongest zone of low-level isentropic upglide/ascent in
association with the eastern extent of the low. Meanwhile, a few
(more reliable) CAM`s including the HRRR and RRFS-A indicate what
has been discussed for a few days, the potential for a mesoscale
deformation band NW of the surface low. It`s unclear to what
degree this band will cause issues with, perhaps a zone of higher
QPF somewhere from near Lafayette, to Hattiesburg. Diving deeper,
GFS deformation parameters flag a maximized zone in this corridor
from H6 to H7, indicative of the front end of more elevated
isentropic upglide banding and attendant confluence meaning, the
synoptic field "makes sense" for this to form and it`s encouraging
, in terms of confidence to see the CAM`s starting to illustrate
it. Again, impacts are unclear, but widespread QPF totals of
around 1-2" is looking pretty good (and slightly lower in regards
to trends) however, it`s cautioned locally higher amounts could be
possible depending on where/how or if any mesoscale banding
forms. Did also let the mention of thunder ride with this update,
as there appears some subtle/minor elevated instability in this
layer aloft, producing MUCAPE in the 100-200J/kg range, enough for
an occasional ruble of thunder but not a whole lot. It`ll be
closer to the low and to the east/south in the better low-level
moisture and available lift/shear where we could see some locally
strong to severe storms, perhaps getting pretty close to
Plaquemines parish again - depending on the exact low placement.
This activity should remain mainly offshore but will closely
monitor.

Once this low departs to our northeast, the rain will exit the
area before/around daybreak Tuesday with CAA building into the
region. Tuesday is looking chilly with breezy NW winds and
clearing skies, likely seeing sunshine atleast by the late
morning to afternoon hours. KLG

&&

.LONG TERM...
(Tuesday night through Saturday night)
Issued at 1031 PM CST Sat Nov 29 2025

By Tuesday night/Wednesday morning, the bulk of the continental
polar airmass settles in nicely across the region, with ~1025mb
high building into the TN valley region. It`s looking cold, with
temperatures likely reaching below freezing for the northern 1/3
of the area. The deterministic 01Z NBM is coming in warmer
compared to the ensemble suite, and did nudge lows down slightly
as we`ll likely decouple from mixing and winds die down,
promoting maximized radiational cooling processes. This brings
freezing temperatures to right at the I-10/12 corridor on north,
with upper 20`s across SW MS and traditionally colder Pearl
River/Pascagoula drainage basins.

As the high shifts east Wednesday, return flow will steadily build
back into the region. But, that means our next system will take
shape over the SW US, as a west-coast trough dives south into the
four-corners region, phasing up with a cut-off low over the Baja
region, accelerating moisture/PVA east promoting yet another
surface low to develop over the southern US/NW Gulf. Details this
far out remains to be seen, with some slight indifference in
guidance, however, is enough to confidently say we`ll in some way
see rain later next week (Thursday & Friday time frame) but stay
tuned as we unveil more details as we get closer. KLG

&&

.AVIATION...
(12Z TAFS)
Issued at 518 AM CST Sun Nov 30 2025

Vis and cigs will lower through the day as SHRA set in. Levels
should be in and around IFR but will bounce in and out of LIFR to
IFR to MVFR with light to mod rainfall. SHRA will break up a bit
after noon today with only -SHRA affecting any given terminal
thorugh the night while keeping flight levels in and around IFR.


&&

.MARINE...
Issued at 1031 PM CST Sat Nov 29 2025

A front will approach coastal/nearshore waters today and come to a
slowdown and eventually stall introducing intermittent light
showers, with better chances along the immediate coast. Winds will
shift out of the north behind the front with winds picking up in the
10-15kt range later this afternoon/evening to 15-20kts overnight
Sunday into Monday, mainly across the Tidal Lakes, nearshore
sounds/gulf waters and southwest into waters west of the mouth of
the MS. A Small Craft Advisory is now in effect for these areas
through noon Monday. It is highly cautioned that the eventual
strength of the low will determine the potential for stronger winds
to persist beyond thru early Tuesday, leading to the possibility of
the Small Craft Advisory to be extended in time, though confidence
for now remains low. The main impacts will be periods of heavy rain,
and some strong to potentially severe thunderstorms producing winds
>34 knots, locally enhanced waves/seas and waterspouts. Once the low
approaches land over coastal MS/AL, a front will sweep across the
area allowing winds to shift out of the NW and waves/seas increase
steadily to around 5-7ft for offshore Gulf zones thru Tuesday, where
additional headlines could likely be required. High pressure settles
in mid-week calming down winds and waves/seas, however, confidence
is increasing that we`ll see another system approach Gulf waters
later in the week with another increase in winds and shower/storm
activity. KLG

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  56  42  55  40 /  90  40  70  90
BTR  61  45  58  43 /  80  40  70  90
ASD  68  46  64  43 /  50  20  60  90
MSY  70  53  66  50 /  50  20  60  90
GPT  69  50  66  47 /  40  20  50  90
PQL  71  48  67  46 /  40  20  50  90

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...Small Craft Advisory from 6 PM this evening to noon CST Monday
     for GMZ530-532-534-536-538-550-552-555-557-570-572.

MS...None.
GM...Small Craft Advisory from 6 PM this evening to noon CST Monday
     for GMZ532-534-536-538-550-552-555-557-570-572.

&&

$$

SHORT TERM...KLG
LONG TERM....KLG
AVIATION...TE
MARINE...KLG