Flash Flood Guidance
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769
AWUS01 KWNH 100336
FFGMPD
OHZ000-KYZ000-MIZ000-INZ000-ILZ000-100935-

Mesoscale Precipitation Discussion 0601
NWS Weather Prediction Center College Park MD
1135 PM EDT Tue Jul 09 2024

Areas affected...Eastern IL...Central/Northern IN...Western
OH...Southern Lower MI

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

Valid 100335Z - 100935Z

SUMMARY...Post-T.C. Beryl will continue off to the northeast
overnight, bringing heavy rain and a threat of flooding to the OH
Valley and Lower Great Lakes region.

DISCUSSION...The late evening GOES-E IR satellite imagery shows
Post-T.C. Beryl continuing to advance off to the northeast across
the OH Valley. An axis of moderate to heavy rain continues to
focus north of the storm track in association with a well-defined
mid-level deformation zone and coincidence with an axis of strong
frontogenetic forcing. This is being facilitated by a deep layer
TROWAL associated with the deeper layer and very warm/moist
southerly flow advecting north ahead of Beryl`s track.

The heaviest rains within the deformation zone are generally
focused across east-central to northeast IL through northern IN
and into southern Lower MI. To the southeast of this corridor,
there are areas of heavy rain that include some stronger elevated
convective elements, and this is generally noted across central IN
through western OH. A nose of stronger instability associated with
a convergent southerly low-level jet of 40 to 50 kts continues to
lift north and over a warm front that extends east of Beryl`s
circulation, and MUCAPE values of 500 to 1000 J/kg are noted
across central IN through western OH. Greater instability
meanwhile is situated closer to the OH River over southern IN
through southern OH where MUCAPE values of 1000 to 2000 J/kg are
noted.

Rainfall rates with the stronger convective elements closer to the
warm front have recently been on the order of 1" to 2"/hour, with
rates back into the deformation zone persistently in the 0.50" to
0.75"/hour range. The PW environment remains quite tropical over
the OH Valley with values of 1.8 to 2.2 inches based on a
combination of 00Z RAOB and GPS-derived information, and this
environment should continue to favor efficient rainfall processes
for locally enhanced rainfall rates overnight.

Additional rainfall totals overnight will likely reach as high as
2 to 4 inches with isolated heavier totals not out of the question
where any stronger convective cells persist. These rains will
promote a threat for additional flooding overnight, including some
localized urban flash flooding concerns.

Orrison

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

ATTN...WFO...CLE...DTX...GRR...ILN...ILX...IND...IWX...LOT...

ATTN...RFC...NCRFC...OHRFC...NWC...

LAT...LON   42748504 42588330 41488254 40268284 39078399
            39158502 40028564 40198608 40208713 40138782
            40438843 41108830 41838748 42368634