211
FXUS64 KLCH 221753
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
1153 AM CST Fri Nov 22 2024

...New AVIATION...

.SYNOPSIS...
Issued at 350 AM CST Fri Nov 22 2024

Cold and clear conditions are noted across the region this morning
beneath dry northwesterly flow aloft. Reinforcing surface high
pressure continues to build southward into the region, and this
will help extend the streak of fall-like weather through Saturday.
Temperatures across much of the region range from around 40 to
the middle and upper 40s amid light winds.

There is still the potential for frost and/or freeze conditions
across central LA tonight as the center of the ridge settles over
the lower MS Valley. However, conditions will quickly change by
Sunday into early next week as the high slides east, and warm and
moist air returns over the region. The outlook for the
Thanksgiving holiday travel period shows a rather unsettled
pattern as a series of fronts bring a chance of showers, with the
first one on Tuesday followed by a secondary front on Thanksgiving
Day. The second front will bring much cooler temperatures for the
Thanksgiving weekend.

24

&&

.SHORT TERM...
(Today through Sunday night)
Issued at 350 AM CST Fri Nov 22 2024

The dry NW flow aloft will continue through tonight as the potent
upper low over the northeast states moves off the east coast. The
aforementioned surface high will build south over the area today,
settling over the lower MS Valley tonight. This will sustain cool
air advection over the area, with highs today ranging from around
60 across central LA to around 70 across lower SE TX.

Winds are expected to become calm overnight which, combined with
the clear skies, will facilitate efficient radiational cooling.
Some of the coldest temperatures of this recent stretch of cool
weather are expected, with lows potentially reaching the freezing
mark in a few isolated locations across central LA. Deterministic
NBM values have been running above the 90th percentile fairly
consistently on overnight lows the past few nights, so opted to
use a blend of NBM with NBM50 to reduce these inherent warm
biases. Some patchy frost will also be likely across parts of
central LA.

Saturday morning will be the last of the chilly conditions as the
surface high will move east of the area, with southerly winds
developing. The pattern will become more zonal aloft, with a
shortwave crossing the western CONUS which will induce surface low
development over the central high plains on Sunday. This will
herald a pronounced warming trend that will be quite noticeable
by the end of the weekend, along with an increase in low level
humidity. Daytime highs are expected to rebound back into the
upper 70s/around 80 by Sunday afternoon, while overnight lows
Sunday night will be back into the 60s.

24

&&

.LONG TERM...
(Monday through Friday)
Issued at 350 AM CST Fri Nov 22 2024

The progressive low amplitude pattern will continue into the early
part of the week. The first in a series of shortwaves will move
east across the central US, bringing a cold front into the region
late Monday into early Tuesday. Strengthening southerly low level
flow will support sufficient moisture return, with PWATs climbing
to 1.2 to 1.4 inches. Low level forcing should be adequate to
allow for some scattered showers to develop along the front as it
moves through the area Monday night.

Weak high pressure ridging will transit the region on Tuesday,
accompanied by a brief wind shift. But the high will quickly slide
east, with southerly winds redeveloping by Wednesday as the next
low pressure system takes shape across the southern plains. A few
showers will be possible on Wednesday, with rain chances
increasing into Thanksgiving Day as the surface low moves east,
stretching its attendant front across the area. Forecast
soundings suggest moderate to strong shear over the region, but
instability could be limited due to considerable cloud cover.
Thus, conditions could support a few thunderstorms on Thursday,
but the risk for any strong to severe storms appears low at this
time.

Guidance appears to be in a little better agreement this morning
that the front will move east of the area Thursday night, with
Canadian high pressure building south over TX by the end of the
week. Gusty northerly winds are expected to usher cooler
temperatures back into the area in time for Black Friday shopping.

24

&&

.AVIATION...
(18Z TAFS)
Issued at 1152 AM CST Fri Nov 22 2024

High pressure centered over the northern gulf coast today will
maintain light northerly winds and clear skies with winds becoming
calm tonight. The high will begin to shift east of the area
Saturday morning turning light winds easterly and eventually
southeasterly.

Jones

&&

.MARINE...
Issued at 350 AM CST Fri Nov 22 2024

Surface high pressure building south over the area will produce a
gradually diminishing offshore flow over the coastal waters.
Winds will veer to the east on Saturday, then to the south by
Sunday as the surface high moves east.

A somewhat unsettled pattern is expected to develop during the
week. The first of a couple of cold fronts is expected to move
through the area late Monday into Tuesday, producing a brief wind
shift in its wake. Southerly winds will quickly redevelop and
strengthen by Wednesday prior to another front that will arrive
late in the week. Exercise caution or advisory headlines may be
needed at times during the week.

24

&&

.PRELIMINARY POINT TEMPS/POPS...
AEX  34  65  39  76 /   0   0   0   0
LCH  40  68  50  77 /   0   0   0   0
LFT  40  68  48  79 /   0   0   0   0
BPT  45  73  54  81 /   0   0   0   0

&&

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

$$

SHORT TERM...24
LONG TERM....24
AVIATION...66