Mesoscale Precipitation Discussion 1004
NWS Weather Prediction Center College Park MD
537 AM EDT Thu Nov 01 2018

Areas affected...Southern Louisiana...Southern MS...Southern AL

Concerning...Heavy rainfall...Flash flooding possible

Valid 010936Z - 011436Z

Summary...A line of thunderstorms producing locally heavy rainfall
will move across portions of southern Louisiana and
southern/central Mississippi through this morning. With intense
hourly rainfall rates exceeding 1-1.5", localized flash flooding
will be possible through 14z.

Discussion...Recent GOES-16 IR imagery shows cloud tops continue
to cool across portions of southern Louisiana where a line of
convection has persisted most of the early morning hours. An axis
of MLCAPE of 1000-1500 J/kg exists across portions of the region
per latest RAP mesoanalysis, which is helping to sustain the
convection this morning. Recent radar returns from KILX and KDGX
indicate hourly rates of 1-2" are associated with the line as it
moves steadily east.

Clusters of storms ahead of the main line will merge/intersect
across portions of southeast LA...southern MS this morning,
enhancing the potential for repeated rounds of locally heavy
rainfall. The latest HREF shows the greatest probabilities of
exceeding FFG are in and around the New Orleans metro area through
12z, which then could spread into southern MS through 14z.
Additional rainfall totals of 1-2" (locally 3") will be possible
through this time.

The main limiting factor for a greater flash flood potential is
the forward speed of the line. However, merging clusters ahead of
it could enhance rainfall totals and given its proximity to
sensitive urban areas, some localized flash flooding will be
possible.

Taylor

ATTN...WFO...BMX...JAN...LCH...LIX...MOB...

ATTN...RFC...LMRFC...SERFC...

LAT...LON   32538936 32528900 31948768 30928755 30198757
            30108847 29468878 29218887 29018895 28999030
            29059065 29369139 30389023 31359008