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FXUS64 KLCH 212010

Area Forecast Discussion
National Weather Service Lake Charles LA
310 PM CDT Sat Oct 21 2017

Wx map shows continued east southeast flow across the region, with
an increasing pressure gradient across TX 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.



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 



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