016
FXUS64 KLCH 170830
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
330 AM CDT Fri May 17 2024

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

.SHORT TERM...
(Today through Sunday night)
Issued at 330 AM CDT Fri May 17 2024

Early morning sfc analysis shows an area of low pressure over our
ern zones with a trailing frontal boundary noted extending along the
upper TX/swrn LA coast. Water vapor imagery shows a wswrly flow
aloft over the region thanks to a filling low approaching the Red
River Valley...the shortwave responsible for this evening`s
strong/severe storms has departed the region while a pair of more
subtle disturbances lie upstream. Speaking of said convection, local
88Ds show pretty much all of it has now moved east of the
Atchafalaya with just a few straggling cells noted over lower
Acadiana and the adjacent coastal waters. Otherwise, observations
show a mostly cloudy and fairly seasonal night ongoing.

Still expecting one more day/night of active weather across the
forecast area today. The combination of the disturbances aloft with
the lingering sfc boundary and good persistent moisture (forecast
soundings indicate PWAT values up to 1.9 inches, especially over our
sern zones) plus daytime heating should lead to another round of
shower/thunderstorm development by this afternoon. Current thinking
at this time is that the bulk of the development should come on the
south side of the boundary (essentially the sern 1/3 of the forecast
area) although forecast soundings indicate enough instability/CAPE
on the backside of the front to allow for at least widely scattered
showers/storms today. Activity looks to really crank up later this
evening into the overnight hours as the primary shortwave works its
way across the area, maximizing lift. Convective parameters from
forecast soundings indicate the potential for damaging wind gusts
and large hail (isolated tornadoes can`t be ruled out, but don`t
seem as likely with fairly straight line hodographs) across our sern
zones, and thus SPC is highlighting this portion of the area in a
slight risk for severe through tonight (a narrow band around the
edge of this area is in a marginal risk). Likewise, the highest
forecasted QPFs are in these same areas and suspect WPC will
maintain a slight risk of excessive rainfall in their upcoming day 1
outlook.

As far as the Flood Watch goes, have made no changes to it this
morning. Elected to keep the sern zones out of it even with the
higher projected rainfalls today since antecedent conditions aren`t
too bad despite some good downpours over the past few hours. On the
flip side, elected to maintain the watch over our nwrn zones which
have just been hammered with periods of heavy rains recently...and
despite the lower POPs and much lower projected QPFs today, any
convection which fires up over this area has the potential to drop
sufficient amounts to certainly aggravate the already very wet
conditions up there.

Once the bulk of the precip moves out late tonight through tomorrow
morning (some lingering lighter convection looks possible over
the Atchafalaya Basin into Saturday afternoon), the remainder of
the short term looks dry as ridging begins building over the
region.

25

&&

.LONG TERM...
(Monday through Friday)
Issued at 330 AM CDT Fri May 17 2024

High pressure will be along the Atlantic coast at the beginning of
the work week keeping a south flow in place. A ridge aloft will
stretch from South Texas into the Lower MS Valley. Hot and humid yet
dry conditons are anticipated for the first half of next week as this
pattern remains in place. Temperatures are expected to be above
climo averages for the date.

Past mid week the upper ridge may shift east as a system pushes into
the plains. A few showers and storms may return to the area as the
ridge exits, but as of now the forecast keeps the bulk of the
convection removed to the north closer the upper disturbances
pushing from the plains into the Mid MS Valley.

05

&&

.AVIATION...
(06Z TAFS)
Issued at 1136 PM CDT Thu May 16 2024

Some lingering shower activity will be possible near the KARA
terminal through about 17/09z. Otherwise, MVFR to IFR conditions
from low clouds and possible patchy fog will be the main story
during the night into early Friday morning.

Still some uncertainty to where the potential thunderstorm
complex will develop on Friday afternoon. Therefore, just broad
brushed each terminal with a PROB30 group between 1718z/1724z.

Rua

&&

.MARINE...
Issued at 330 AM CDT Fri May 17 2024

Once the existing headlines on the CWF expire later this morning,
don`t expect to see any more added back in through the period as
prevailing high pressure maintains generally light winds on the
coastal waters.

25

&&

.PRELIMINARY POINT TEMPS/POPS...
AEX  82  65  87  66 /  20  30  20   0
LCH  84  70  87  70 /  40  40  20   0
LFT  87  72  88  72 /  50  60  30   0
BPT  85  69  89  70 /  40  30  10   0

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...Flood Watch through late tonight for LAZ027>033-044-045-141>143-
     152-241>243.

TX...Flood Watch through late tonight for TXZ180-201-259>262-515-516-
     615-616.

GM...None.
&&

$$

SHORT TERM...25
LONG TERM....05
AVIATION...07