FXUS64 KLCH 181152
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
652 AM CDT Mon May 18 2026

...New AVIATION...

.KEY MESSAGES...

- Breezy and warm conditions will prevail again today with a few 
  showers and thunderstorms developing this afternoon.

- A prolonged period of unsettled weather will develop beginning 
  Tuesday afternoon and continue through the end of the week with 
  high precipitation chances each day.

- Marginal Risk (lvl 1 of 5) for severe weather covering northwest
  portions of the area Tuesday afternoon. Wind and hail will be 
  the greatest hazards.

- Several inches of rain are expected across the region Tuesday
  through next Sunday with a Marginal Risk (lvl 1 of 4) for
  excessive rainfall highlighting all areas each day Tue-Thu with
  more likely beyond.

&&

.DISCUSSION...
(Today through Sunday)
Issued at 1207 AM CDT Mon May 18 2026

A weak upper perturbation / nocturnal jet moving across northeast
Texas made easy work of the moisture flux from today. A north- 
south axis of showers currently exists just west of the Sabine. 
This area will slowly move east thru sunrise and may squeeze a few
showers down to the AEX metro, but largely this shouldn't impact 
our forecast region. 

Morning hours should be quiet, albeit perhaps a bit dreary. Winds
increase with sunrise as the pressure gradient between boundary
present in the Plains and weakening but present high over the
Carolinas. Should be a similar day as far as breeziness goes, but
still not anticipating a prolonged period of definite strong
sustained winds. Thus, a wind advisory is not anticipated at this
time. 

Moisture will continue filtering in, filling out the column,
through the morning. 00Z RAOB reported 1.61 inches PWAT, however
as seen by mesoanalysis, PWAT values 1.80 to 2.00 inches (greater
than 90th percentile) have already surged up the Texas coast, 
helping to generate the area of active showers seen tonight. This 
anomalously moist airmass will remain in place overtop our region,
waiting in place for a forcing mechanism to generate some 
convection. An area of diurnal/seabreeze showers/storms looks to 
develop in south central LA before moving north. The typical quick
downpour, windy summer storm should result. 

The first round of active convection should then arrive by late
Tuesday in the form of a decaying QLCS feature. The act of this
boundary moving southeast will deflect remaining high pressure
influence from the east, leaving the door open for active weather.
A series of disturbances will move over the northwest Gulf from
Wednesday onward bringing about daily chances for widespread
rainfall. From Tuesday nigh to the early weekend, it's reasonable
to expect 2 to 4 inches area-wide with higher local totals. The
flash flooding threat will increase each day with rounds of
rainfall onto semi-wet antecedent conditions, so keep your flash 
flood response plans in the back of your mind as we near the end
of the week. 

11/Calhoun

&&

.AVIATION...
(12Z TAFS)
Issued at 646 AM CDT Mon May 18 2026

While few areas of MVFR BKN ceiling exist this morning. Conditions
will trend borderline VFR / MVFR today as diurnal mixing allow
SCT / BKN cloud bases around 2-3kt through the afternoon. Isolated
chances of precip remain in the forecast so some terminals,
particularly across SETX and well interior SWLA may see VCSH.
Guidance is suggesting potentially heavy precip developing
southward across central LA tonight around dusk. Coastal site TAFs
will update in next TAF package to reflect timing as ceilings
begin to drop and become OVC by evening twilight. 

30 

&&

.MARINE...
Issued at 1207 AM CDT Mon May 18 2026

Tightened pressure gradient will remain in place through at least
Tuesday morning. A boundary of disturbed weather is expected to 
near the region on Tuesday causing all remaining high pressure
influence to back eastward. This decrease in pressure will loosen
the gradient allowing winds and then seas to fall back on Tuesday,
remaining low through the remainder of the week. 

Rain chances increase Tuesday night and will remain elevated
through the rest of the forecast as a series of disturbances cross
the region. Winds will prevail somewhat low and onshore, however
volatile winds and seas could be possible local to storms each
day.

&&

.FIRE WEATHER...
Issued at 1207 AM CDT Mon May 18 2026

Tightened pressure gradient will remain in place through at least
Tuesday morning. A boundary of disturbed weather is expected to 
near the region on Tuesday causing all remaining high pressure 
influence to back eastward. This decrease in pressure will loosen 
the gradient allowing winds to diminish before the arrival of a
very wet and disturbed weather pattern from late Tuesday to the
end of the week. 

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...Small Craft Advisory until 4 AM CDT Tuesday for GMZ450-452-470-
     472.

&&

$$

PUBLIC/FIRE/MARINE...11
AVIATION...30