Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

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415
FXUS64 KLIX 272316
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
516 PM CST Thu Nov 27 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 514 PM CST Thu Nov 27 2025

 - Potential for a brief light freeze Friday morning for some areas
   north of Lake Pontchartrain and along Mississippi coast.
   This is primarily in the Pearl and Pascagoula River Basins.

 - Hazardous marine conditions for much of the next 5 days.

 - Entering a wetter pattern beginning Saturday night into Sunday,
   with a second period of rainfall, possibly heavy, Monday night
   and Tuesday.

&&

.SHORT TERM...
(This afternoon through Friday night)
Issued at 1128 AM CST Thu Nov 27 2025

Upper trough axis looks to be just to the east of the local area
this morning, somewhere around Interstate 65, with ridging over
the Intermountain West. At the surface, high pressure was centered
near the Arkansas-Missouri border. Skies were clear across the
area this morning with temperatures mainly in the 50s and dew
points in the 20s.

The upper ridging to our west flattens quite a bit by Saturday
morning, producing mainly zonal flow across the Gulf Coast States.
The surface high will shift eastward to the Appalachians by that
time. Precipitable water values near 1/3 inch are below the 10th
percentile climatologically, and are expected to remain near that
level through sunset Friday. Even by sunrise Saturday, those
moisture levels are expected to remain below the 50th percentile,
and forecast soundings would indicate no more than perhaps mid level
clouds prior to sunrise Saturday.

Only real concern at this point is the potential for a freeze
overnight tonight. The values currently in the grids would bring any
real threat to primarily the Pearl and Pascagoula River drainages.
Those areas have had a fairly significant freeze already, on the
10th and 11th, but we`ve had an unseasonably warm stretch since
then. Secondary question is whether winds drop off enough tonight to
allow decoupling for radiative cooling to maximize, and drop
temperatures to or below freezing for a climatologically significant
amount of time (several hours). Will hold off on Freeze Warning
for now, but could adjust thinking this afternoon.

One adjustment from pure NBM that was made was to lower daytime
dewpoints to NBM05 to NBM10 to better represent the very dry air
across the area. Wind speeds are a bit below red flag criteria,
but outdoor burning probably isn`t a good idea at this point
unless it is very well controlled.

&&

.LONG TERM...
(Saturday through Wednesday)
Issued at 1128 AM CST Thu Nov 27 2025

Onshore flow commences Saturday morning, with precipitable water
values rebounding to around 1 inch by sunset Saturday. This at
least sneaks above the 50th percentile climatologically. A
northern stream shortwave will move across the Middle Mississippi
River Valley Saturday afternoon and Saturday night, to near Lake
Erie by Sunday morning. This will push a frontal boundary toward
the area Saturday night, and through the area on Sunday.
Precipitable water values only briefly get above the 75th
percentile, so heavy rain threat with that system may not be as
great as earlier thought. Rain amounts around an inch would
actually be beneficial at this point.

Of somewhat greater concern will be the system that is expected to
impact the area Monday night and Tuesday. The GFS and ECMWF are both
forecasting a stronger shortwave to move across the Middle and Lower
Mississippi River Valley, with precipitable water values reaching or
exceeding the 90th percentile. The overnight medium range models
also depict the development of a surface low along the frontal
boundary as it moves across the area Monday night. This would be a
more typical heavy rain threat than the weekend event, with the main
concern timing of the frontal passage and low pressure
development. Rainfall amounts of 1 to 2 inches look to be common. As
this is Day 5-6, would expect details to resolve as the event
gets closer, and with the weekend system `priming the pump`, a
heavy rain/flooding event cannot be ruled out. Another brief shot
of cold air will follow that system.

Current NBM numbers appear to favor the colder solutions for much of
the long range period, but don`t have any real ammunition at this
point to back away from those.

&&

.AVIATION...
(00Z TAFS)
Issued at 514 PM CST Thu Nov 27 2025

A very dry and stable high pressure system over the area will keep
VFR conditions in place at all of the terminals through the entire
forecast period. Winds will remain gusty at NEW through tomorrow
morning as increased thermal mixing over the warmer lake waters
allows some stronger winds of 12 to 15 knots with occasional gusts
over 20 knots to transport down to the surface.

&&

.MARINE...
Issued at 1128 AM CST Thu Nov 27 2025

High pressure will gradually slide to the east over the next 36
hours. With cold, dry air continue to feed over the coastal waters,
will extend the Small Craft Advisory over the open waters until 00z
Saturday, and potentially beyond that point. Will likely need at
least Small Craft Exercise Caution headlines over some or most of
the protected waters Friday afternoon. If there is going to be a
period of less impactful conditions across the waters over the next
5-6 days , it would probably be during the daytime hours on Sunday,
until cold air behind that frontal passage reaches the waters.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  32  56  37  65 /   0   0   0  20
BTR  35  61  42  71 /   0   0   0  10
ASD  32  60  40  70 /   0   0   0   0
MSY  44  61  50  73 /   0   0   0   0
GPT  36  58  43  69 /   0   0   0   0
PQL  31  59  37  68 /   0   0   0   0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...Small Craft Advisory until noon CST Friday for GMZ530-532-534-
     536-538.

     Small Craft Advisory until 6 PM CST Friday for GMZ550-552-555-
     557-570-572-575-577.

MS...None.
GM...Small Craft Advisory until noon CST Friday for GMZ532-534-536-
     538.

     Small Craft Advisory until 6 PM CST Friday for GMZ552-555-557-
     570-572-575-577.

&&

$$

SHORT TERM...RW
LONG TERM....RW
AVIATION...PG
MARINE...RW