Subj : MESO: Nws Weather Prediction Center College Park Md
To   : wx-storm@lists.illinois.edu
From : COD Weather Processor
Date : Sat Aug 05 2023 23:36:03

AWUS01 KWNH 052335
FFGMPD
TNZ000-KYZ000-INZ000-ILZ000-MOZ000-060400-

Mesoscale Precipitation Discussion 0874
NWS Weather Prediction Center College Park MD
735 PM EDT Sat Aug 05 2023

Areas affected...Southern IL...Western KY...Far Southeast MO...

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

Valid 052335Z - 060400Z

SUMMARY...Developing thunderstorms with rain-rates up to 2"/hr
crossing areas of saturated grounds may pose possible risk for
localized flash flooding especially in the near-term.

DISCUSSION...Recent RADAR and Goes-E Vis/EIR loops depict a line
of rapidly developing thunderstorms with numerous overshooting
tops and cooling below -60C.  CIRA LPW/TPW denotes enhanced
pooling of deep layer moisture across S IL extending back upstream
into ESE to SE Missouri; with RAP supporting denoting a slug of
enhanced moisture in the 850mb layer building toward 2-2.25"
totals along/ahead of the developing line.   A fast moving
shortwave can be seen sliding east along the AR/MO line, while
trailing low to mid-level trough from the compact wave over NE IL
into NW IND has resulted in enhanced convergence along the
northeast edge of this wave to support rapid convective
development.

While boundary layer inflow is fairly weak, ample environmental
moisture should support rain-rates up to 2-2.5"/hr.  Though
steering flow/mean cell motions of 20-25kts to the east may limit
duration of heavy rainfall, a few factors still may support
potential for localized flash flooding risk.  The first is
antecedent soil conditions...while core of area recently flooded
over the last week is generally west of the developing line with
1/3hr FFG below 2"/2.5" respectively, there may be a short window
where cells overlap with the compromised areas.  The second is
with stronger low level inflow winds to the deeper steering flow,
there is some potential for back-building along the upwind edge,
particularly in the axis of that enhanced 850mb moisture across
ESE MO.   Still, neither situation is guaranteed and so potential
flash flooding is considered possible and more likely in the next
hour or so than further downstream into Western KY where grounds
are a bit drier and infiltration may be greater.=20=20

Gallina

....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!=
DZ3fjg!_AXWjPKdrXHsLfLqih2SUm34jWxS__NkPhp8U2CcWjkTn_KYK3VdWOCJehG49OCEITK9=
D0spoZ63JhI65_xz9RG75G8$  for graphic product...

ATTN...WFO...LMK...OHX...PAH...

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

LAT...LON   38108814 38108745 37728678 36838683 36648754=20
            36728882 37348963 37788927=20

=3D =3D =3D
To unsubscribe from WX-STORM and you already have a login, go to
https://lists.illinois.edu and use the "Unsubscribe" link.  Otherwise email
Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.14-Linux
 * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

.