898
FXUS64 KLIX 162334
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
534 PM CST Tue Dec 16 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 531 PM CST Tue Dec 16 2025

 - Clouds increase today ahead of the next disturnace expecting to
   bring isolated showers to the area Wednesday into Wednesday
   Night.

 - Confidence increasing for the potential of widespread fog
   Wednesday night into Thursday morning. Location confidence is
   highest along and west of I-59, however density remains in
   question at this time.

 - The next front arrives Thursday, with light to moderate showers
   and a few storms expected. Some stronger storms possible near
   the coast/marine areas Thursday morning.

 - Turning cooler Friday, but not anticipating freezing
   temperatures following this front with a quick warm up expected
   into the upcoming weekend back into the 70`s

&&

.SHORT TERM...
(This afternoon through Wednesday)
Issued at 1003 AM CST Tue Dec 16 2025

Another cold start to the day today as many areas hit the 20`s to
low 30`s yet again. Some areas actually saw colder temperatures
this morning as high pressure promoted strong radiational cooling
at the surface. But, now we begin to see a change in the weather
by first looking at satellite, which shows increasing upper-level
cirrus out of the west. This is out ahead of a broad positive-tilt
shortwave trough/impulse over west Texas down to Baja.
Technically, two embedded impulses within a larger trough, with
the strongest/maximized vorticity and attendant jet max over Baja.
This will be a big player to focus on in the next 24-48 hours but
as of today, downstream acceleration will continue to pump upper-
level moisture over across the Mexican plateau over across the
northern/western Gulf. Clouds will increase today and become
mainly overcast this evening/tonight. Model soundings illustrate
this thick moist layer between H4 to H2, however is ontop of a
very dry subsident layer dominating the mid to low-levels,
basically residual compressional warming aloft left over from the
polar airmass which means moistening will take some time.

Meanwhile at the surface, dewpoints will slowly crawl up, moreso
for areas along and west of the Atchafalya Basin. We could see
some light patchy fog for these areas on west, but not overly
impressed by sfc/low-level fog conditions promoted by weak/subtle
advection and not seeing much, if any strong crossover signal with
dewpoints in the Gulf in the 50`s to near 60. But, some patchy
areas can`t be ruled out. Otherwise, dry/calm tonight.

Going into Wednesday, the noticeable trend/change has now been
both embedded impulses/vort max centers now phasing up together
into a single broad trough over the western Gulf. This appears to
have changed a few things, mainly the degree of downstream
divergence/lift promoting showers and storms developing over the
Gulf. Meanwhile for land areas, we`ll see the aforementioned
strong/deep dry layer moisten up from Virga over time, with some
light showers making it to the surface. PoPs are in the 20`s,
introduced by the NBM which appears plausible. Overall not
anticipating an all-day washout, but enough to cause drops on
peoples windshields. KLG

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 1003 AM CST Tue Dec 16 2025

Wednesday night into Thursday morning, slow/but steady moistening
will draw 50 to eventually low 60 degree dewpoints north
introducing a potential for some fog. REFS ensemble guidance
supports this claim promoting 50-70% <1sm VIS along and west of
I-59, within the best SE return flow. Available moisture, however,
remains in question. It`s by all means not a slam dunk advection
fog regime, but could be enough to drop many areas for several
hours. Will fine tune any dense fog potential as we near closer
but for now, trends are starting to highlight dense fog as a
possibility.

Meanwhile going into Thursday morning, a much stronger/deeper
shortwave impulse flies fast across the northern Rockies into the
central Plains, which will pick up and absorb the impulse over our
area sending it northeast. Few possible scenarios here have
developed, which are interesting.

1) It is distinctly possible now that we`re seeing trends in
greater lift with the lead disturbances and attendant
coastal/marine convection Wed/Wed Night that return flow/recovery
could be hindered meaning, the front could be a bit drier than
anticipated. Still could see showers, just not as widespread
coverage.

2) If we can recover any moisture return ahead of the front, there
is the capability of rebuilding MUCAPE to about coastal SE LA and
MS where a few storms could be possible. While this appears
elevated, especially over land areas, a few strong storms could be
possible. This has been introduced by the recent 12Z REFS but
could be coming in a bit loud/strong with this scenario. Not going
to write it off though.

3) Could be a messy mix of both disorganized scattered convection
in the Gulf, combined with re-developing messy showers from the
front swinging across the area. The lack of strong lift and
noticeable residence of deeper Gulf return flow really keeps a
lid on any deep convection potential only bringing showers and a
few storms, with best chance for storms over coastal areas. This
appears the most likely scenario for now.

Either way, the front swings through during the day on Thursday.
Timing shows we`ll still warm up right ahead of the front, then
turning chilly again Thursday and Friday night. The lack of an
upstream polar connection from the departing (then) longwave
trough supports no freezing temperature plunge like the last
system, but still could dip into the 40`s areawide to 30`s for
protected colder locations. High pressure and large/wide H582dm
ridging builds into the southern US this weekend supporting above-
normal temperatures reaching the 70`s for many. Not bad for those
that don`t like the cold! KLG

&&

.AVIATION...
(00Z TAFS)
Issued at 531 PM CST Tue Dec 16 2025

Prevailing VFR conditions at all terminals and this should hold
through the evening at the very least. Late this evening into
overnight we will start to see some clouds build in, which could
cause some lower ceilings. Some very patchy fog is possible,
mainly for northern and western terminals. This patchy fog could
briefly bring MVFR conditions, but should improve after sunrise.

&&

.MARINE...
Issued at 1003 AM CST Tue Dec 16 2025

High pressure will continue to shift east across the southern mid-
Atlantic coastline today, promoting mainly easterly winds at around
8-10kts. Winds shift from the SE going into Thursday ahead of the
next front sweeping across the area. Showers and a few storms will
be possible Wednesday with a disturbance ahead of the main front,
with another round of showers and storms Thursday. Following the
front, winds will increase 15-20kts to 20-25kts for 20-60nm offshore
Gulf zones and out of the north, likely needing Small Craft
Advisories generally from Thursday night through Friday night. High
pressure settles into the region late-week into the weekend bringing
calm winds and waves/seas. KLG

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  42  64  54  71 /  10  20  40  70
BTR  46  66  56  76 /  10  20  30  50
ASD  42  65  53  72 /  10  30  50  50
MSY  51  65  59  74 /  10  30  50  50
GPT  46  63  54  68 /   0  30  60  70
PQL  41  64  52  70 /   0  30  50  70

&&

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

$$

SHORT TERM...KLG
LONG TERM....KLG
AVIATION...HL
MARINE...KLG