MD 0014 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR SOUTHERN LOUISIANA

Mesoscale Discussion 0014
NWS Storm Prediction Center Norman OK
0938 PM CST Wed Jan 06 2021

Areas affected...Southern Louisiana

Concerning...Severe potential...Watch unlikely 

Valid 070338Z - 070545Z

Probability of Watch Issuance...5 percent

SUMMARY...Thunderstorms overspreading the region through Midnight-1
AM are generally expected to remain sub-severe, but sporadic,
localized damaging wind gusts are possible, with an isolated tornado
not completely out of the question, particularly near coastal areas.

DISCUSSION...An organized mesoscale convective system has been
maintained beneath strongly difluent mid/upper flow, just ahead of
the vigorous short wave trough which continues to pivot toward the
Sabine River/Piney Woods vicinity.  A number of lower/mid
tropospheric cyclonic circulations have developed within the line,
which has been advancing eastward around 30-35 kt, within sheared,
30-60+ kt in the 850-500 mb layer (veering from southerly to
west-southwesterly with height).  

Despite the strong forcing and favorable kinematic environment,
thermodynamic profiles characterized by generally weak lapse rates
and rather modest to weak low-level moisture (even over the
northwestern Gulf of Mexico) remain limiting factors concerning
severe weather potential.  Across and inland of Louisiana coastal
areas, at least a shallow near-surface stable layer lingers, with
little appreciable increase in surface dew points across southern
Louisiana as temperatures have begun to cool.

The recent gust to 37 kt at Lake Charles is probably indicative of
the general wind gust potential with the squall line as it
progresses eastward into the lower Mississippi Valley through
05-07Z.  However, localized stronger, potentially damaging, wind
gusts and perhaps an isolated tornado might not be entirely out of
the question, mainly along a weak baroclinic zone near immediate
coastal areas.

..Kerr/Grams.. 01/07/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...JAN...LIX...LCH...

LAT...LON   30199219 31319199 31309023 29299044 28259229 28379309
            30199219 

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