272
AWUS01 KWNH 042235
FFGMPD
MNZ000-IAZ000-KSZ000-NEZ000-SDZ000-050400-

Mesoscale Precipitation Discussion 0590
NWS Weather Prediction Center College Park MD
634 PM EDT Fri Jul 04 2025

Areas affected...Eastern Nebraska...Southeast South Dakota

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

Valid 042233Z - 050400Z

SUMMARY...Widespread thunderstorms containing 1.5-2.0"/hr rainfall
rates may produce flash flooding this afternoon and evening,
especially in low-lying poor drainage areas and in more urbanized
communities.

DISCUSSION...GOES-19 satellite imagery and Doppler Radar show no
shortage of thunderstorms traversing central Nebraska this
afternoon. Storms are developing as far south as central Kansas as
an integrated vapor transport (IVT) topping 700 kg/m/s advects a
plentiful source of moisture northward. Storms are gradually
moving north and east into eastern Nebraska and southeast South
Dakota where RAP forecasts depict PWs between 1.75-2.0" and MLCAPE
between 1,000-2,000 J/kg with little to no capping present.
Focusing on the PWs, these PWs are topping the 99.5th
climatological percentile per NAEFS. Plus, RAP soundings within
the highlighted region sport low-mid level RH values averaging 90%
and warm cloud layers over 14,000ft deep, supporting warm rain
processes within these storms. There is also sufficient vertical
wind shear to sustain these segments of thunderstorms for several
more hours as they continue their northeast heading.

Much of the highlighted region is either in D0-D2 drought
conditions, so for most areas, this rainfall will be largely
beneficial. However, it is the concern for back-building
thunderstorms as the southerly IVT remains healthy into the
overnight hours to potentially allow for training, moisture-loaded
thunderstorms in some cases. Flash flooding is possible this
afternoon and evening, especially in low-lying spots that drain
poorly and in communities with a greater concentration of
hydrophobic surfaces.

Mullinax

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

ATTN...WFO...FSD...GID...GLD...LBF...OAX...

ATTN...RFC...KRF...NWC...

LAT...LON   44499787 44469729 44279681 43929640 43639635
            43079649 42399677 41669714 41069746 40639786
            40249833 39669905 39479942 39320020 39440054
            39900083 40540082 41120046 41749982 42299936
            42869901 43409876 43889852 44379810