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fxus64 klch 220006 
afdlch

Area forecast discussion
National Weather Service Lake Charles la
606 PM CST Wed Feb 21 2018

Discussion...
22/00z taf issuance.

&&

Aviation...
bulk of convection has moved north of the terminals, with aex
currently sitting between two narrow bands that are lifting north.
Gusty southerly winds will gradually diminish over the next hour
or two, with MVFR cigs to prevail. Ocnl rain showers and possibly an isltd
ts can be expected tonight into early Thursday mainly at
aex/lch/bpt, but uncertainty regarding timing/coverage warrant no
more than a vc mention at any of these sites. With winds expected
to diminish to less than 10 knots this evening, cigs are expected to
lower to IFR with possible vsby reductions in patchy fog overnight.
Cigs/vsbys will lift Thursday morning with southerly winds again
strengthening and bcmg gusty although not as strong as they were
today.

24

&&

Previous discussion... /issued 335 PM CST Wed Feb 21 2018/

Discussion...radar depicting numerous showers and a few
thunderstorms over interior southeast Texas into central
Louisiana. Elsewhere, isolated to scattered showers are in place
with the exception of Acadiana now absent of rains. Convection is
along and ahead of an approaching cold front in the process of
stalling. Boundary progged to come to rest along a line from
northeast Louisiana to just west of Beaumont then then along the
Texas coast. Front will remain in this area into Thursday before
retreating. Earlier high end precipitable water values should be
trending down and this appears verified by the latest water vapor
imagery as drier mid-level air advects in. Morning lch sounding-
came in an impressive 1.58 inches. Normal for this time of year is
around 0.75 inches.

Will be maintaining Wind Advisory for the southern half of the
area through 6 PM. Tornado Watch for portions of the area will be
allowed to expire at 5 PM. Flash Flood Watch for the north and
western portions of the forecast area will end at midnight.

Will be maintaining respectable pops overnight and into Thursday
until frontal boundary retreats. As mentioned, will allow Flood
Watch to continue as plenty of moisture for any activity that
fires could result in locally heavy and potentially flooding
rainfall, especially with wind profiles that would suggest
training potential that we have already seen today. Highest
threat remains over interior southeast Texas and central Louisiana,
trending downward across the remainder of the watch area.

Rain chances diminish for Thursday night and the remainder of the
week. Maintaining low end pops at this time while temperatures
will continue to trend well above the norm.

Marine...an approaching cold front will stall later today from
northeast Louisiana to along the Texas coast. This feature along
with good upper support will maintain scattered showers and
thunderstorms through Thursday especially over the western portion
of the northwest Gulf. The front will retreat late Thursday with
rain chances then diminishing. With a long fetch of south to
southeast winds continuing through the week, seas will remain
somewhat elevated offshore, while dense fog development remains
possible nearshore.

23

&&

Preliminary point temps/pops...
aex 65 78 65 80 / 80 50 30 50
lch 68 78 67 79 / 60 50 20 40
lft 70 80 68 80 / 40 30 20 50
bpt 68 78 67 79 / 60 50 30 30

&&

Lch watches/warnings/advisories...
la...Flash Flood Watch until midnight CST tonight for laz027-028-030-
031-041.

Wind Advisory until 6 PM CST this evening for laz041>045-052>055-
073-074.

Texas...Flash Flood Watch until midnight CST tonight for txz180-201-215-
216-259>262.

Wind Advisory until 6 PM CST this evening for txz215-216.

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