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fxus64 klch 212340 

Area forecast discussion
National Weather Service Lake Charles la
640 PM CDT Sat Oct 21 2017


Areas radars show thunderstorms ongoing across areas along and
east of Interstate 49. These thunderstorms will continue over the
next few hours resulting in thunderstorms in the vicinity for kaex, kara, and klft.
Additionally, tempo MVFR ceiling and visibility restrictions will
be possible as thunderstorms move over klft. Further west, skies
have cleared to VFR for kbpt and klch and these conditions will
prevail through the rest of the evening. Thunderstorms should come
to an end around 9 PM and give way to VFR conditions for the
entire area. Winds will remain light out of the east to southeast.


Previous discussion... /issued 310 PM CDT Sat Oct 21 2017/

wx map shows continued east southeast flow across the region, with
an increasing pressure gradient across Texas ahead of the next sfc and
upper level trough to affect our region Sunday. Radar showing scattered
showers streaming across c and SW la, with scattered to numerous
showers and thunderstorms increasing across c and SC la, mainly
along and east of I-49. Shortterm updates this afternoon included
raising pops to 60% for c and SC la, with the earlier expansion of
40-50% westward.

A larger longwave mid/upper level trough moving eastward over the
central U.S. Will affect our region overnight and Sunday with
healthy chances of showers and thunderstorms. This is expected to
bring around one half to one inch of rainfall with locally higher
amounts across the region. Only a marginal risk of severe weather
expected across lower Acadiana eastward for Sunday, with general
thunderstorm outlook for the remainder of the area per Storm
Prediction Center day 2 outlook.

With the passage of the upper level trough Sunday, a cold front
is expected to bring cooler and drier air for Sunday night and
Monday. A much stronger cold front is expected for late Monday
night into Tuesday morning. This will bring back the much cooler
temperatures, expecting widespread 40s by Wednesday morning. A
warming trend will commence for Thursday, followed by another cold
front bringing another round of showers and thunderstorms for
next Friday/Saturday time frame. Still have timing differences
this far out among the long range models.


moderate onshore flow will continue through Sunday in advance of a
cold front. Scattered showers and thunderstorms will be possible
tonight, with activity increasing on Sunday as the cold front
moves through the region. Offshore flow will develop behind the
front, strengthening overnight into Monday as cooler and drier air
moves into the area. A secondary cold front will move through the
region Tuesday, reinforcing the strong offshore flow through
midweek. At this time, exercise caution conditions appear likely
behind the initial front on Monday, with winds/seas reaching
advisory thresholds in the wake of the second front on Tuesday.



Preliminary point temps/pops...
aex 70 79 52 75 / 30 90 20 10
lch 73 82 57 77 / 30 90 20 10
lft 72 82 57 76 / 30 90 20 10
bpt 73 81 55 78 / 30 90 10 10


Lch watches/warnings/advisories...

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