049
FXUS64 KLIX 160250
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
950 PM CDT Thu Aug 15 2024

...New UPDATE...

.UPDATE...
Issued at 948 PM CDT Thu Aug 15 2024

Have removed mention of precipitation overnight from all but lower
portions of the southeast Louisiana coastal parishes, where
convection could return around sunrise. Hourly temperature and dew
point grids have been adjusted to reflect current and expected
trends overnight. ZFP and CWF have already been transmitted.

&&

.UPDATE...
Issued at 644 PM CDT Thu Aug 15 2024

Cold pool driven convection continues to dive southward across
southeast Louisiana. Main effects have been wind gusts to about 40
mph, and very heavy rain. Several areas have received upwards of 2
to 3 inches of rain in an hour. Convection has weakened somewhat
with the loss of daytime heating, but it will likely still take
another couple hours for storms to shift westward into southwest
Louisiana and/or southward into the coastal waters.

Will be updating shortly to remove the heat related headline from
today and to hopefully depict near-term weather trends.

&&

.SHORT TERM...
(This evening through Friday night)
Issued at 244 PM CDT Thu Aug 15 2024

Convective development has been noted across southern Mississippi
over the past hour. Higher mid-level moisture and a weak boundary
has aided in that development this afternoon. A pocket of higher
DCAPE has been noted across the Florida Parishes with values of
900-1000 j/kg where the low-levels have been able to mix out.
With the cluster of thunderstorms coming from Southern Mississippi
heading that way, that area could see a higher threat of strong
to severe winds. Also, SBCAPE and MLCAPE values are around 5000
j/kg and 3500 j/kg, respectively, so that cluster and its
associated outflow boundary should continue to push through the
area moving to the southwest. That main cluster should push
through the area throughout the afternoon and evening until the
sun goes down or it moves out of the area.

Tomorrow will be very similar to today in terms of temperatures
and convective coverage. PW will still remain elevated around
2-2.2 inches across the area tomorrow as the pocket of mid-level
moisture hangs around. This, with the help of the weak boundary
across the area, will aid in storm development tomorrow. Much of
the convection will again be dictated by outflow boundaries as
well as sea and lake-breeze boundaries. Surface mixing will help
DCAPE get up to around 900-1000 j/kg tomorrow, similar to day.
Thus strong to severe damaging winds seems possible again tomorrow
with the strongest storms. Convective development seems a little
later tomorrow with the northerly flow aloft, so temps were bumped
up slightly, bringing us to heat advisory conditions. Of course,
if development happens earlier, then the heat will not be as bad
tomorrow.

&&

.LONG TERM...
(Saturday through Wednesday night)
Issued at 244 PM CDT Thu Aug 15 2024

The mid-level ridge will continue to slide westward this weekend,
putting us more firmly into northerly flow aloft. This will help
us stay somewhat dry this weekend. The surface high over the
eastern CONUS is also expected to slide westward and place itself
over us this weekend. That will also help to keep us dry, but it
will also cause us to heat up. So, heat headlines will likely be
needed into the weekend.

Medium-range guidance suggests that troughing over the eastern
CONUS will throw down another front sometime either late Sunday or
Monday. This time of year, it is hard for a front to make it all
the way down here, but with northerly flow, it is possible. If
that were to happen, we will "cool" down slightly while upping
rain chances. That is something to just monitor at this point.

&&

.AVIATION...
(00Z TAFS)
Issued at 644 PM CDT Thu Aug 15 2024

Near term concern is convection, primarily at KNEW/KMSY/KHUM. Any
strong wind impacts likely to diminish by 01z. Beyond that point,
should be primarily VFR conditions with a cirrus overcast
everywhere with possible exception of KGPT. Will not carry TSRA
for Friday afternoon at this time, and reassess for 06z package.

&&

.MARINE...
Issued at 244 PM CDT Thu Aug 15 2024

Mostly benign marine conditions will persist through the forecast
period. Thunderstorm development will be most likely each morning
during the period. A surface high looks to move over the waters
this weekend as parent ridge slides westward across the SW CONUS.
A front is possible to move through the area early next week, so
that will be a focus of rain.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  74  95  75  95 /  30  50  20  40
BTR  77  98  78  98 /  40  60  30  30
ASD  77  96  76  95 /  30  50  20  30
MSY  78  95  79  95 /  40  60  30  30
GPT  79  93  78  93 /  20  50  20  30
PQL  78  96  76  96 /  20  40  10  30

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory from 10 AM to 7 PM CDT Friday for LAZ034>037-039-
     046>048-056>060-064>071-076>090.

GM...None.
MS...Heat Advisory from 10 AM to 7 PM CDT Friday for MSZ068>071-077-
     083>088.

GM...None.
&&

$$

SHORT TERM...JZ
LONG TERM....JZ
AVIATION/UPDATES...RW
MARINE...JZ