595
FXUS64 KLCH 150313
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
1013 PM CDT Fri Jun 14 2024

...New UPDATE...

.UPDATE...
Issued at 1005 PM CDT Fri Jun 14 2024

A small cluster of thunderstorms has formed late this evening near
Vermilion Bay and Saint Mary/New Iberia Parishes, moving west.
This activity is expected to be short-lived as it moves over
western portions of Vermilion and West Cote Blanche Bays into
eastern Vermilion Parish. Other than adding some low PoPs in this
area and making some minor adjustments to hourly temps and winds
for this evening, the current forecast is on track with generally
quiet conditions expected through Saturday as high pressure
prevails aloft.

24

&&

.SHORT TERM...
(Tonight through Sunday night)
Issued at 252 PM CDT Fri Jun 14 2024

The short term will be a period of transition as the current dry
air mass departs.

A ridge aloft and high pressure at the surface is across the deep
south this afternoon with a very dry air mass in place locally.
PWAT on this morning`s KLCH sounding was 0.83" which is near the
daily min for the date. This dry air mass has kept most cloud
cover sparse and allowed temps to rise into the 90s which is a
few degrees above normal for the date after a somewhat cool
morning.

Through tonight and Saturday the ridge will shift east toward the
Atlantic coast. An inverted trough that extends southwest from
Florida into the Yucatan will begin to move west around the base
of the ridge. Higher moisture will begin to work into the local
area as the trough moves farther into the gulf. Saturday is
anticipated to be dry once again, however dewpoints are expected
to remain higher then nudge upwards through later Saturday and
through the night.

A few showers will begin to the return to the coastal waters
Saturday night with scattered convection working into the area
Sunday, but mainly late in the day. Moisture will increase during
the day Sunday. PWAT values will increase to over 2" along the
coast of LA by sunset Sunday and may increase to near the daily
max for the date in Lower Acadiana. This will occur as the
inverted trough slowly moves west across the gulf and central
America. The local area will be on the northern fringe of the
trough with moisture being pulled northwest around the edge of the
departing ridge and setting the stage for a wet extended period.

&&

.LONG TERM...
(Monday through next Thursday)
Issued at 252 PM CDT Fri Jun 14 2024

Looking like a wet period for the early to middle part of next week.

The upper level ridge over the northwest Gulf will diminish with the
upper level ridge becoming centered over the southeast US and off
the coast. This will develop a broad east to west wind flow across
the Gulf of Mexico, and this will push the inverted trough and
associated deep tropical moisture that has been over the
northwest Caribbean into the Florida area to the west.

The deep moisture and trough will reach the forecast area by the
beginning of the period on Monday then push it gradually west
through Thursday. Currently, the most likely scenario is for the
inverted trough axis to stay on the weak side, or if it does develop
into a more closed off cyclone, for the closed low to stay well
south of the forecast area and across the southern Gulf of Mexico.
Just how closed off or strong the low gets will impact how much of
the deep moisture stays over the forecast area. For now, will keep
the scenario of basically just a sloppy weak trough feature.

The air mass will definitely have a tropical origin with highly
anomalous moisture values. Precipitable Water values will range from
2.2 to 2.4 inches which is well above the 90th percentile for this
time of year of around 2 inches, and closer to max moving averages
and daily highs. Also, 1000-500 mean layer relative humidity values
will be over 80 percent and warm cloud layer will be between 13k-15k
feet, which all means that convection will be highly efficient warm
process rain makers.

Usually in these air masses, plenty of nocturnal activity occur over
the Gulf and right along the coast, and with low convective
temperatures, this activity will spread quickly inland during the
day.

Reliable QPF numbers show total rainfall amounts from Monday through
Wednesday averaging 3-6 inches from along and south of the I-10
corridor, and 1 to 3 inches north of the I-10 corridor. Of course,
there could be some locally higher amounts, but way too soon to
pinpoint any of that. With the expected rainfall, Marginal to Slight
Risk of Excessive Rainfall (level 1 and 2 out of 4) that may lead to
flooding has been outlined for the Day 4 and 5 periods which is
Monday and Tuesday. This outlooks will probably be refined over the
next few days and will probably have to be extended into Wednesday
also.

Any other impacts will be breezy conditions for right along the
coast and offshore with building seas and swells, to go along with
some higher than normal tides.

If there is some good news, although it will be muggy, high
temperatures should be a little below normal during the period.

07/Rua

&&

.AVIATION...
(00Z TAFS)
Issued at 626 PM CDT Fri Jun 14 2024

FEW/SCT CU near the Acadiana terminals will dissipate over the
next few hours, with SKC to prevail overnight. No significant
changes are expected through the period, with light/variable winds
tonight becoming E-SE 4-8 KT in the afternoon with FEW-SCT CU
again developing.

24

&&

.MARINE...
Issued at 252 PM CDT Fri Jun 14 2024

Light winds and low seas will continue into Saturday, however the
pressure gradient will tighten Sunday into early next week. Winds
and seas will build Sunday through mid week as an inverted trough
passes to the south. SCA conditons are anticipated Monday night
through Thursday. Tides are also expected to run above normal and
minor coastal flooding may be a concern at times of high tide.

&&

.PRELIMINARY POINT TEMPS/POPS...
AEX  69  96  72  95 /   0   0   0  20
LCH  74  95  74  93 /   0  10   0  40
LFT  75  97  76  93 /   0  10   0  60
BPT  74  95  75  93 /   0   0   0  30

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...None.
&&

$$

SHORT TERM...05
LONG TERM....07
AVIATION...24