Mesoscale Precipitation Discussion 0638
NWS Weather Prediction Center College Park MD
1027 AM EDT Wed Jul 17 2024
Areas affected...South-Central AR...Northwest MS...Western
TN...Southern MO
Concerning...Heavy rainfall...Flash flooding possible
Valid 171426Z - 171900Z
Summary...The heavy rainfall threat from the ongoing MCS across
southern MO and central AR will continue through 2 pm local time,
with additional instances of flash flooding possible where storms
train over the same general areas.
Discussion...Recent infrared and visible satellite imagery still
indicates an expansive MCS centered over north-central Arkansas
this morning, although the event has likely peaked in intensity
and a slow weakening trend has begun based on a gradually warming
anvil canopy. Regional Doppler radars show new convection firing
on the southern edge of the complex near the Interstate 40
corridor, and also across southern Missouri, with moderate to
heavy stratiform rain ongoing over the Ozarks of northern
Arkansas.
Portions of north-central Arkansas have already picke up in excess
of six inches of rainfall overnight, and therefore flash flood
guidance values are severely reduced over those areas. Even
moderate to heavy stratiform rainfall could cause additional
flooding issues for those areas. The most recent HRRR seems to
have a reasonably good depiction of ongoing radar trends, but it
appears likely to be underdone with 6-QPF through the early
afternoon, particularly for areas in the general vicinity of
Little Rock and points south and west.