615
FXUS64 KLIX 131731
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1231 PM CDT Tue Aug 13 2024

...New AVIATION...

.UPDATE...
Issued at 937 AM CDT Tue Aug 13 2024

Performed a forecast update this morning to bring in the latest
near-term guidance thru this evening and match to obs/trends.
Really very little change in the state of the troposphere compared
to the previous 24 hours. Very similar "warm" thermal profile
aloft, similar low-level and total PW values (maybe slightly
greater moisture aloft). As we warm up and mix out today, we
still won`t see much in the way of available energy with a rather
"skinny" SBCAPE profile thanks to the aforementioned warmer
thermal profile aloft. Given the little change from yesterday,
same can be said about today. Subtle weakness (albeit still
considered ridge dominant) synoptic pattern will aid in
suppression, but could still see scattered showers/few storms
bubble up, especially collocated with deeper surface moisture
across SE LA and the Atchafalaya Basin - where PoPs were bumped up
a tad more today. Otherwise, additional forcing mechanisms like
seabreeze/lakebreeze boundaries and residual outflow boundaries
from earlier storm development will be the foci for development
and propagation today. No one main threat with any stronger storm
stands out, but some could be gusty with dangerous lightning the
main risks and if updrafts root to any boundary
interactions/collisions, could briefly see a tropical funnel or
waterspout especially across the same areas of far SE LA and the
Atchafalaya Basin. Did increase PoPs also to mention an isolated
shower or storm east across the Northshore to coastal MS,
targeting where the seabreeze/lakebreeze may pop development this
afternoon. All activity will come to an end around sunset with a
calm/clear night.

Additionally, looks like the 50th percentile verified the best for
yesterdays high which means yes, the deterministic is coming in
slightly too warm likely from the recent week(s) high bias of
extreme heat we`ve been dealing with. Performed the same slight
bump down with highs that places many areas still in the upper
90`s. No changes to the Heat Advisory in effect, but be on the
lookout for another Advisory likely for tomorrow for the afternoon
package. KLG

&&

.SHORT TERM...
(Today through Wednesday)
Issued at 247 AM CDT Tue Aug 13 2024

Sfc moisture is making its way back into the area slowly as dew pts
creep up toward 80F. And as you have heard, this will couple with
the strong heating each day to bring about heat advisories. Not much
change in these conditions for the next few days. The cause of this
remains the large stacked high centered over northern TX today which
will migrate a bit more east toward northern LA, at least this is
the H3 level position. Some sh/ts will be able to get started in the
heat of each day but will be isolated to scattered at best.

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 247 AM CDT Tue Aug 13 2024

The H3 high will eventually center itself over the SE CONUS by Thu
as it moistens and weakens during this time frame. A new SW CONUS
stacked high will then take up residence where the current high
vacated. This new stacked high is currently located near 30N 127W
which is over the EASTPAC. As this new high quickly moves east into
the continental US, it will help intensify our NW flow bringing some
storms from the north as an upper level trough axis remains over the
east. With this and a weak short wave moving through by the end of
the week, we may see a quick rise in precip numbers for the weekend.
These would be traveling from the north and several could be strong
or even severe. Timing looks like late Sat or overnight Sat. Some
will definitely welcome the rain but no large scale changes at the
moment.

&&

.AVIATION...
(18Z TAFS)
Issued at 1225 PM CDT Tue Aug 13 2024

Have seen quite a bit of cumulus development over the last hour
with most cloud bases at or above FL040. While there isn`t much in
the way of TSRA at issuance time, do expect to see at least
isolated development in the next hour or two with precipitable
water values near 2 inches, and most of the area near or above
forecast convective temperatures. Wind fields remain rather weak,
so we`ll see propagation along meso and microscale boundaries
rather than actual movement. Will start out with VCTS at most
terminals and amend if it appears a terminal could have direct
impacts. Convection is forecast to dissipate prior to sunset.
Forecast soundings for tomorrow are quite a bit drier than today,
and expect convection to be extremely isolated tomorrow afternoon,
if there is any at all.

&&

.MARINE...
Issued at 247 AM CDT Tue Aug 13 2024

Wind direction will be around the compass through the week but will
be rather light at 10kt or less. Higher winds and seas will be in
and around storms.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  97  75  98  75 /  10  10  20  10
BTR  98  79 100  79 /  30  10  20  10
ASD  98  77  99  78 /  30  10  20  10
MSY  96  79  98  80 /  30  10  20  10
GPT  96  78  98  79 /  40  10  20  10
PQL  99  77 102  77 /  30  10  20  10

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory until 7 PM CDT this evening for LAZ034>037-039-
     046>048-056>060-064>071-076>090.

GM...None.
MS...Heat Advisory until 7 PM CDT this evening for MSZ068>071-077-
     083>088.

GM...None.
&&

$$

SHORT TERM...TE
LONG TERM....TE
AVIATION...RW
MARINE...TE