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000
FXUS64 KLIX 202058
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
358 PM CDT Sat Apr 20 2024

...New SHORT TERM, LONG TERM, AVIATION, MARINE...

.SHORT TERM...
(This evening through Sunday night)
Issued at 349 PM CDT Sat Apr 20 2024

A fairly broad upper level trough is currently moving east through
the Great Lakes. The southern side of this feature is relatively
flat at this time which is why the associated cold front draped
across central Louisiana and southern Mississippi is struggling to
make southward progression. The cold front will be basically
crawling south in the CWA this afternoon. Visible satellite hasn`t
changed much from this morning and shows only partly cloudy skies
south of the boundary across the Florida Parishes and coastal
Mississippi. This has allowed for decent warming which should
increase CAPE in the lower to mid levels. As that boundary reaches
this region later this aftn, a few thunderstorms could develop
along and north of I-12 in LA and southern portions of LA. Latest
CAMs show various versions of this and am in agreement with this.
Severe potential not particularly high due to weak shear but
fairly steep mid level lapse rates could be enough for a few
marginally severe storms with hail.

A shortwave on the backside of the northern trough is moving on a
much farther south trajectory and will be passing through the mid to
lower Mississippi Valley Sunday afternoon. This is what`ll be needed
to finally drive that cold front completely through the CWA on
Sunday morning. Ample moisture in place with lift from the front
will be a good setup for increasing showers. Model soundings
continue to show minimal instability anywhere throughout the column.
Thus, thinking it`ll be fairly tough for much thunder to develop and
therefore now only have isolated thunderstorms in the zone
forecasts. Overall QPF shouldn`t be impactful generally speaking
with areal amounts under an inch. Coverage forecast of 80% could
still be too low.

MEFFER

&&

.LONG TERM...
(Monday through Friday night)
Issued at 349 PM CDT Sat Apr 20 2024

This cold front won`t be particularly strong being that a shortwave
it driving it, so only looking at a day (Monday) of below normal
temps with moderating conditions quickly returning as well as
above normal temps Tuesday onward. Precip forecast still looking
generally dry with zonal flow transitioning into ridging. That`ll
be supportive of current moderating temps expected.

MEFFER
&&

.AVIATION...
(18Z TAFS)
Issued at 349 PM CDT Sat Apr 20 2024

A mix of MVFR and VFR cigs dominate the short term with most sites
becoming VFR as lower cloud decks dissipate around sunset. Later
this evening and overnight, cloud decks will lower back to MVFR or
IFR with the potential for pockets of light fog. A few terminals may
see moderately dense fog at times. Expect conditions to start
improving a couple/few hours after sunrise Saturday. Scattered
showers may start to develop mid morning Saturday, thus have
introduced VCSH on the most recent TAFs sent.

MEFFER
&&

.MARINE...
Issued at 349 PM CDT Sat Apr 20 2024

A surface high pressure is centered in the western Atlantic and
extending across the Gulf of Mexico. The western periphery of this
ridge is being broken down by approaching surface trough to the
north of the area. Thus, onshore flow is weakening with most of the
coastal waters staying light and variable until a cold front comes
through early Sunday morning. Cold air advection won`t be
particularly strong with this boundary and thus likely only looking
at about 12 to 18 hours of low-end Small Craft conditions.

MEFFER
&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  51  62  43  69 /  90  40   0   0
BTR  59  68  48  74 /  70  30   0   0
ASD  59  70  48  74 /  60  60   0   0
MSY  63  71  55  72 /  60  60   0   0
GPT  58  69  49  73 /  50  60   0   0
PQL  58  71  47  75 /  40  60   0   0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...Small Craft Advisory from 7 PM Sunday to 10 AM CDT Monday for
     GMZ530-532-534-536-538-550-552-555-557-570-572-575-577.

MS...None.
GM...Small Craft Advisory from 7 PM Sunday to 10 AM CDT Monday for
     GMZ532-534-536-538-550-552-555-557-570-572-575-577.

&&

$$

SHORT TERM...ME
LONG TERM....ME
AVIATION...ME
MARINE...ME