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359
FXUS64 KLCH 201135
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
635 AM CDT Sun Aug 20 2017

.DISCUSSION...
12Z TAFS

&&

.AVIATION...
Scattered showers and thunderstorms expected to develop this
afternoon as the area comes under the influence of an inverted
upper trough pushing through the gulf of Mexico. Short range
guidance indicating that the greatest chance of precipitation will
be at BPT and LCH this afternoon, but given the generally chaotic
nature of the primarily diurnally driven convection, opted to
include VCTS at all sites from 18Z today through 01Z Monday. Away
from convection, winds will remain light out of the east to
southeast through the period.

Jones

&&

.PREV DISCUSSION... /issued 400 AM CDT Sun Aug 20 2017/

DISCUSSION...
Early morning sfc analysis shows high pressure centered off the
mouth of the Mississippi River, maintaining essentially calm winds
over the forecast area. Water vapor imagery shows a flat ridge
aloft stretching from the Desert Southwest through the srn Plains
to the sern CONUS, while a tutt low is noted over the ern Gulf
drifting wwd. Satellite imagery/regional 88Ds show earlier
convection over the Gulf waters has dissipated, leaving behind
PPINE conditions over the region this morning.

Forecast area to remain under the influence of the weak ridging
aloft, although with increasing contributions from the approaching
tutt over the Gulf. Initial round of showers/storms comes in the
form of weak sea breeze convection later this morning along the
coast, while the bulk of the action is expected this afternoon
with heating. Most medium/long-range models indicate a swath of
wwd-moving moisture associated with the mid/upper low passing the
area this afternoon which is also noted in high-res guidance...
thus slightly higher POPs were brushed in over the wrn zones which
continue into early evening before dissipating with loss of
heating. Main story again remains the heat as max temps this
afternoon are progged to reach the mid 90s, although with a little
higher cloud cover not expecting readings to get quite as warm as
Saturday. With dewpoints running mostly in the mid 70s over much
of the area, apparent temps again look to peak around 105...thus
no heat advisory appears needed for today. Stay tuned...

As the tutt low drifts farther wwd, we should begin to see
additional moisture pumped in on the backside of the system which
should lead to somewhat better rain chances through the early part
of the work week...including Monday when all protected eyes will
be turned towards the sun. At this time, it unfortunately appears
that cloud cover will be rather extensive around the time of the
eclipse, especially across the swrn 1/2 of the area. Under the
increased cloud cover/precip, max temps are progged to drop back
to more normal summertime values into mid-week. Rain chances get a
further boost for the latter half of the week as the low meanders
around the region. Meanwhile a trof digging over the ern CONUS is
progged to push a weak front toward the region later in the
week...however sufficient moisture is noted behind this feature to
allow for continued diurnal convection into the weekend.

MARINE...
No flags are currently advertised on the coastal waters through
the period with high pressure remaining mostly in control.

&&

.PRELIMINARY POINT TEMPS/POPS...
AEX  95  75  94  74 /  30  10  30  20
LCH  94  77  93  77 /  40  10  30  30
LFT  94  77  94  77 /  30  10  40  30
BPT  94  77  93  76 /  40  10  40  20

&&

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

$$


AVIATION...66