345
AWUS01 KWNH 090355
FFGMPD
TNZ000-KYZ000-ILZ000-MSZ000-MOZ000-ARZ000-090830-

Mesoscale Precipitation Discussion 0246
NWS Weather Prediction Center College Park MD
1154 PM EDT Wed May 08 2024

Areas affected...central AR into portions of lower to middle MS
Valley

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

Valid 090353Z - 090830Z

SUMMARY...An advancing line of thunderstorms combined with
development ahead of the line will likely support areas of
training and potential for localized 2-3 inch totals from central
AR into portions of the lower/middle MS Valley.

DISCUSSION...At 0330Z, a pre-frontal, broken line of thunderstorms
extended from the southern IL/MO border into north-central AR,
located within the warm sector of a frontal cyclone to the north.
Cells of a more discrete nature were noted out ahead of the broken
line, extending from the MO Bootheel to east-central AR. SPC
mesoanalysis data from 03Z showed impressive MLCAPE values of 2500
to 4000+ J/kg along with PWATs of 1.5-1.7 inches from the Arklatex
into the MS Valley, with diffluent flow aloft aiding ascent within
southwesterly flow aloft.

The broken line of convection is expected to continue advancing
toward the east-southeast through 08Z while possibly picking up
speed across portions of the MS/OH River confluence as the cold
front advances downstream over the next few hours. The northern
portion of the line may push out ahead more quickly, relative to
the southern portion over central AR, allowing for alignment with
mean steering flow from the SW to WSW. Cell mergers due to
discrete cellular activity ahead of the main line may also support
increased rainfall rates with 1-2 in/hr likely at times. While the
overall movement of convection should limit rainfall totals over
most areas, localized 2-3 inch totals through 07Z may result in
localized flash flooding across the region.

Otto

...Please see www.wpc.ncep.noaa.gov for graphic product...

ATTN...WFO...LZK...MEG...PAH...SGF...

ATTN...RFC...ABRFC...LMRFC...NWC...

LAT...LON   37308960 36728906 35958839 35418851 34668952
            34309142 34419250 34849306 35689283 36719113