AWUS01 KWNH 200054
FFGMPD
MOZ000-ARZ000-OKZ000-KSZ000-200650-

Mesoscale Precipitation Discussion 1085
NWS Weather Prediction Center College Park MD
853 PM EDT Tue Sep 19 2023

Areas affected...nern OK, sern KS into swrn MO, nwrn AR

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

Valid 200050Z - 200650Z

Summary...The threat for flash flooding will increase across
northeastern OK/southeastern KS into southwestern MO and
northwestern AR through 07Z. Rainfall rates of 1-2 in/hr are
expected to develop from training and backbuilding of storms
overnight. Localized storm totals over 3 inches will be possible.

Discussion...Regional radar imagery at 00Z showed a few
showers/thunderstorms extending from southeastern KS into
northwestern AR, located ahead of a mid-level vorticity max in
southeastern KS. These storms were elevated, located north of a
warm front analyzed from southwestern KS into northeastern TX.
Precipitable water values in central OK into southwestern MO
ranged from 1.3 to 1.6 inches (recent GPS data and 00Z SGF RAOB)
with estimated MUCAPE of ~500 to 2000 J/kg...highest toward the
southwest (SPC mesoanalysis). Aloft, an upper level jet max of 100
to 110+ kt was located from near ABQ to the Red River, placing
eastern OK within the divergent left exit region, where flow was
also diffluent ahead of an upper trough axis located over central
KS.

Forecasts from the RAP indicate the low level jet will increase to
near 45 kt over central OK by 06Z, supporting increasing
isentropic ascent and cell coverage north of the warm front. The
increased overrunning of the surface boundary is expected to focus
the development of convection near/north of the 925 mb reflection
of the warm front, beneath divergent/diffluent flow aloft. The
orientation of the elevated frontal boundary and steering flow
will be similar, allowing for the potential for training and
repeating rounds of cells. There will also be the potential for
slow moving cells farther north into KS/MO where 850-300 mb layer
mean wind speeds will be less than 10 kt near the slow moving
vorticity max.

While soils are dry from a lack of rain in recent weeks and flash
flood guidance is correspondingly high (3+ inches in 3 hours), an
isolated threat for flash flood will still exist, though it may be
limited to urban areas and other locations of poor drainage.

Otto

ATTN...WFO...ICT...LZK...OUN...SGF...TSA...

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

LAT...LON 38029445 37949396 37569349 37249335 36689322
36369328 35889343 35399376 35119422 35129551
35429733 36299784 36829730 37089688 37509624
37889543

= = =
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* SLMR 2.1a * "Gasoline clears my sinuses!" - Fred G. Sanford
* Origin: Ilink: CCO - capitolcityonline.net (454:1/105)