278
FXUS64 KLIX 201126 AAA
AFDLIX

Area Forecast Discussion...UPDATED
National Weather Service New Orleans LA
526 AM CST Thu Nov 20 2025

...NEW AVIATION...

.KEY MESSAGES...
Updated at 517 AM CST Thu Nov 20 2025

- Widespread dense fog this morning.

- A weak cold front will bring a chance for rain tonight and
  Friday.

- Another weak cold front will bring additional chances for rain
  Monday night and Tuesday.

&&

.SHORT TERM...
(Tonight through Saturday night)
Issued at 1022 PM CST Wed Nov 19 2025

A progressive southern stream pattern will remain in place through
the short term period with a series of shortwave ridges and
troughs sliding through the Lower Mississippi Valley and Gulf
South. Initially, the region will continue to remain under the
influence of a departing shortwave ridge axis, and this will keep
conditions warm and unusually muggy for this time of year.
Additionally, the light winds and high humidity in place will
allow for an extensive fog bank with areas of embedded dense fog
to continue to spread across the region in the next few hours.
Dense fog probabilities remain very high at 60 percent or greater
across a large portion of the forecast area, and a dense fog
advisory is in effect through 9 am. This fog will persist through
the mid- morning hours before clearing as temperatures warm and
daytime thermal mixing occurs.

By the evening hours, increasingly difluent flow aloft will begin
to take hold as the ridge pushes further to the east and a
negatively tilted shortwave trough axis ejects from New Mexico
into north Texas and Oklahoma. At the same time, a plume of deeper
tropical moisture will feed in on the back of increasingly
stronger southerly flow across the forecast area. The combination
of moisture and increased forcing aloft will support scattered
shower development Thursday night into Friday. A few
thunderstorms may also form, but weak mid-level lapse rates will
limit overall instability and keep overall updraft development
and storm intensity on the lower end. Any storms that form will
be weak and very short- lived.

The parent shortwave driving this weak convective activity will
begin to shear out and fully dissipate by Friday evening over the
Ohio Valley. A weak frontal boundary is expected to slide into
the area during the day on Friday and then stall and gradually
dissipate along the coast by Friday evening as the parent system
dies out. Although the thermodynamic support is still limited,
enough forcing along this weakening boundary will allow for
scattered showers and few thunderstorms to continue developing
into the afternoon hours. Overall, rain totals should be very
light with maximum rainfall of half an inch or less anticipated.
The front will fully dissipate Friday night and a building
shortwave ridge axis moving in from the west will be the primary
feature impacting our weather on Saturday. With no real cold or
dry air advection occurring, temperatures will remain well above
normal with highs in the upper 70s and lower 80s and lows in the
60s through the entire short term period. Humidity will also
remain very high, and additional rounds of dense fog are expected
to form both Friday night into Saturday morning and again Saturday
night into Sunday morning.

&&

.LONG TERM...
(Sunday through Wednesday night)
Issued at 1022 PM CST Wed Nov 19 2025

Little change in the overall upper level pattern is expected in
the first half of next week. A very progressive southern stream
will keep pushing shortwave ridges and troughs through the Gulf
South. Sunday will see a building shortwave ridge over the region.
This will keep temperatures a good 10 to 15 degrees above average
and a prevailing light onshore flow will also keep conditions
fairly humid Sunday into Sunday night. As temperatures cool
overnight, conditions once again look prime for fog to form Sunday
night into Monday morning.

Heading into Monday afternoon, the ridge will quickly shift to the
east as another shortwave trough moves into the Plains states.
This system will track to the east very quickly and is expected to
be in the Great Lakes region by Tuesday evening. This system is
expected to remain fairly strong as it moves to the east, so a
trailing cold front will have a better chance of clearing the
coast. Ample warmth and moisture ahead of the front and a broad
region of increasing omega associated with the passage of the
upper level trough axis will support another round of scattered
shower activity. Once again, despite the warm and moist low level
conditions, mid-level lapse rates remain fairly weak Monday night
into Tuesday. With instability remaining limited, only a few
thunderstorms should fire up as the front moves through on
Tuesday and these storms will remain weak and short-lived.

Weak cold air advection will take hold Tuesday night into
Wednesday as a Pacific based airmass moves into the area.
Temperatures will cool slightly, but overall readings will remain
a good 5 degrees warmer than average for late November with highs
in the mid 70s and lows in the upper 50s and lower 60s.
Additionally, the front is expected to hang up just offshore in
the coastal waters over this period as the parent upper level low
quickly pulls into eastern Canada. This front will serve as a
focusing mechanism for some isolated to widely scattered shower
activity Tuesday night into Wednesday.

&&

.AVIATION...
(12Z TAFS)
Issued at 526 AM CST Thu Nov 20 2025

Ongoing dense fog has again developed this morning. Most terminals
are LIFR right out of the gate. Fog should dissipate mid morning
leading to VFR conditions this afternoon. Overnight, cloud cover
will begin to increase with MVFR conditions expected toward the
end of the cycle. A few showers may also develop late
tonight...covered with PROBs for now. The VIS reductions with the
increase in cloudiness looks to be more limited. (Frye)

&&

.MARINE...
Issued at 1022 PM CST Wed Nov 19 2025

Fog will be the primary maritime concern this morning across the
sounds and tidal lakes. This fog will linger into the late morning
hours before clearing and a dense fog advisory is in effect for
these areas. By the afternoon hours, an approaching low pressure
system and front will bring stronger southerly winds of 15 to 20
knots and slightly higher seas to the waters Thursday night into
Friday. Scattered showers and a low threat of thunderstorm will
accompany this weakening front on Friday. Winds will calm over the
weekend to less than 10 knots as a high pressure system over the
eastern Gulf becomes more dominant over the waters. However,
another low pressure system will once again push winds and seas
higher on Monday and Tuesday. Southerly flow should increase back
into the 15 to 20 knot range over this period. Another round of
showers and a few thunderstorms will also develop over the waters
as this next storm system moves through.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  78  64  80  64 /   0  60  80  20
BTR  80  67  83  66 /   0  50  60  10
ASD  78  64  80  64 /   0  50  60  10
MSY  78  68  81  67 /   0  50  60  10
GPT  74  65  76  66 /   0  30  60  10
PQL  76  63  77  65 /   0  20  40  20

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Dense Fog Advisory until 9 AM CST this morning for LAZ034>037-
     039-046>048-056>060-064-065-070-071-076>090.

GM...Dense Fog Advisory until 10 AM CST this morning for GMZ530-532-
     534-536-538.

MS...Dense Fog Advisory until 9 AM CST this morning for MSZ068>071-
     077-083>088.

GM...Dense Fog Advisory until 10 AM CST this morning for GMZ532-534-
     536-538.

&&

$$

SHORT TERM...PG
LONG TERM....PG
AVIATION...RDF
MARINE...PG