531
AWUS01 KWNH 200208
FFGMPD
TNZ000-KYZ000-INZ000-ILZ000-MOZ000-ARZ000-200803-

Mesoscale Precipitation Discussion 1093
NWS Weather Prediction Center College Park MD
1007 PM EDT Wed Aug 19 2026

Areas affected...southeastern Missouri, southern Illinois, western
Kentucky, far northwest Tennessee, and far southwestern Indiana

Concerning...Heavy rainfall...Flash flooding likely

Valid 200203Z - 200803Z

Summary...Areas of training convection are expected to materialize
and cause instances of flash flooding through 08Z/3a central.

Discussion...Robust convective development was noted just
northwest of Poplar Bluff in the past hour.  The convection was
likely tied to 1) increasing low-level flow across northeastern
Arkansas and resultant convergence in the vicinity of the
developing storms, and 2) the glancing influence of a passing
mid-level shortwave trough over northern Missouri.  The storms are
also supported by very steep mid-level lapse rates (7-8 C/km based
on mesoanalyses and the most recent 00Z SGF RAOB).  The lapse
rates and low-level moisture was supporting 1500-2500 J/kg MLCAPE
and 1.8 inch PW, respectively, suggestive of heavy rainfall
potential.  While storms may move eastward at an appreciable rate
initially (~30 knots), increasing low-level flow/convergence will
eventually support development of a complex of storms that
exhibits some elements of forward-propagation, training, and
backbuilding over time.

Some concern exists that areas of repeating/training heavy
rainfall will occur over southeastern Missouri, which as
relatively low FFG in a few areas (around 1-1.5 inch/hr) due to
rain that fell over the past 24 hours between Poplar Bluff, Cape
Girardeau, and points northwestward.  FFGs are slightly higher
with eastward extent into Kentucky, although 2 inch/hr thresholds
should be exceeded especially where heavy rainfall can persist
locally.  Flash flooding is expected in at least a few areas given
the scenario, with the threat spreading eastward from Missouri
(initially) through central Kentucky through 08Z/3a central.

Cook

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

ATTN...WFO...LMK...LSX...LZK...MEG...OHX...PAH...SGF...

ATTN...RFC...KRF...MSR...ORN...TIR...NWC...

LAT...LON   38068828 37888666 37208599 36548631 36178936
            36649195 37689183 37929056