504
FXUS64 KLIX 272041
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
341 PM CDT Mon May 27 2024

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

.SHORT TERM...
(This evening through Tuesday night)
Issued at 340 PM CDT Mon May 27 2024

After a hot and generally dry Memorial Day weekend, temperatures
will be trending back down some. Although we likely won`t get down
to normal temps, at least shouldn`t be flirting with record highs.
These cooler temps come thanks to an upper level trough that`s
pushing south out of Canada. The first of a few embedded shortwave
troughs is now passing across the Ohio Valley. The frontal boundary
associated with the trough isn`t cold but definitely a bit drier.
Locally today, still watching seabreeze convergence boundaries for
afternoon convective potential. Best chance through the next few
hours will probably be in SELA along/south of Lake Pontchartrain.
Earlier some activity tried to get going but the CAP aloft knocked
them down pretty quickly. Did notice a gravity wave in SW LA racing
eastward. Although timing would have to be perfect for this feature
to help spark convective initiation, it bears watching.

Moving into Tuesday, shortwave trough will help to drive the parent
upper trough farther south across the southeastern US on Tuesday.
This will bring the associated frontal boundary closer to the CWA.
Even though 500mb heights locally will be lowering as the ridge
that`s kept the area to hot lately suppresses, compressional warming
will keep highs in the mid 90s just one more day. Much like today,
the potential continues for late afternoon convection with more than
ample instability aloft. Very conditional threat with CAP aloft.
After than, finally start cooling things down on Wednesday with near
normal temps for the first time in what seems like awhile.

MEFFER
&&

.LONG TERM...
(Wednesday through Sunday night)
Issued at 340 PM CDT Mon May 27 2024

The medium range still has a number of uncertainties but the main
one is the strength of the L/W trough over the eastern 3rd of the
CONUS by Thursday. A slightly deeper trough is promoting a better
chance of seeing moderate northwest flow aloft. 2nd is what ever
disturbance being advertised in the southern Plains and E Texas is
actually there and able to continue to work down the northwest flow.
Pretty large discrepancies when looking at the models with the the
ECMWF and its ensemble mean being the drier and warmer solution
while the GFS/GFES/GEM/GEPS favor a slightly cooler and wetter fcst.
This split has been the case for the past 48 hours and the NBM
appears to be putting a little more weight in the cooler/wetter
side. Right now with nothing to really grasp will stick closer to
the NBM and see if we can get a better idea in the next 24-36 hours.

Thursday and Friday at this time could be much nicer than what we
have seen today and what is expected tomorrow. We should have a
little more northwest flow aloft Thursday and perhaps into Friday
and it looks like we will see overnight convection decaying to our
west and northwest with decent cloud cover blowing off over the
area. Also there is some indication that we could see possibly a
backdoor style cold front (well compared to the mid 90s of today and
Tuesday) much of the guidance is suggesting highs in the upper 80s
to near 90. Combine that with the possibility of rain and decent
cloud cover and mid 80s is possible. The biggest question is can we
get convection. A lot will really depend on if we can get a
disturbance or two to move into eastern TX and then continues to
slide under the building ridge to our north. If that occurs then
there is a good chance of scattered convection Thursday. Friday may
be a little more difficult as the ridge should continue to build to
the south and will try to weaken the northwest flow. If the ridge is
able to phase with the broad ridging in the Gulf and west Gulf coast
then we probably get blocked with a drier and warmer fcst than what
we are currently advertising for Thursday.

Through the weekend things continue to remain uncertain. The pattern
is progressive and is changing every 2 to 3 days which should start
to slow down as we move deeper into the Summer. Timing the troughs
and ridges along with the strength of each is the issue and down
here along the Gulf coast, these features could be highly dictated
on convection the day and night before. At this time if looks like
we could move back under northwest flow Saturday with a decent shot
of convection. That would also likely help keeps things on the
slightly cooler side with highs still in the mid 80s to possibly
lower 90s. However, that swings back to the other side with a ridge
building over the southern Plains and quickly shifting east across
the Lower MS Valley late Sunday. If it is a little slower then
perhaps we have another decent shot of scattered convection.

/CAB/
&&

.AVIATION...
(18Z TAFS)
Issued at 340 PM CDT Mon May 27 2024

A scattered to broken CU field has remains in place across the
entire region outside of the lake shadow. Visible satellite and line
of more enhanced cumulus development along a convergence zone from
KGPT to KHUM. Showers did pop up over coastal MS but have since
dissipated, likely due to strong inversion aloft. There`s still some
time left in the day for more activity to develop along this
boundary. Confidence isn`t particularly high but will still carry
tempo groups or VCTS at terminals in that region. Otherwise, MVFR to
VFR ceilings will persist this afternoon and overnight.

MEFFER
&&

.MARINE...
Issued at 340 PM CDT Mon May 27 2024

Surface high pressure currently centered just north of the Bahamas
and extends westward across the entire Gulf of Mexico. A cold front,
located near the LA/AR border, will approach the local area from the
north which will weaken the pressure gradient between it and the
surface ridge. Thus, should see a weakened wind field and seas/waves
the remainder of this week.

MEFFER
&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  69  93  68  85 /  20  20  10  30
BTR  77  96  73  89 /  20  20  10  30
ASD  75  96  72  90 /  20  20  10  20
MSY  79  94  76  89 /  20  20  10  30
GPT  75  94  73  89 /  20  10  10  20
PQL  73  96  69  91 /  20  10  10  20

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory until 8 PM CDT this evening for LAZ034>037-039-
     046>048-056>060-064-065-071-076>090.

GM...None.
MS...Heat Advisory until 8 PM CDT this evening for MSZ068-077-083-084-
     086-087.

GM...None.
&&

$$

SHORT TERM...MEFFER
LONG TERM....CAB
AVIATION...MEFFER
MARINE...MEFFER