318
AWUS01 KWNH 260628
FFGMPD
ILZ000-MOZ000-IAZ000-KSZ000-NEZ000-261225-

Mesoscale Precipitation Discussion 0803
NWS Weather Prediction Center College Park MD
226 AM EDT Sat Jul 26 2025

Areas affected...Northeast KS...Northern MO...Southern
IA...Western and Central IL

Concerning...Heavy rainfall...Flash flooding likely

Valid 260625Z - 261225Z

SUMMARY...Showers and thunderstorms will be developing and
expanding in coverage over the next several hours. Very heavy
rainfall rates along with concerns for cell-training will likely
result in scattered to numerous areas of flash flooding. Locally
significant and dangerous urban flash flooding will be possible.

DISCUSSION...GOES-E satellite imagery shows a slow-moving
mid-level vort center/trough over far southeast NE and northeast
KS which will be advancing gradually into areas of southwest IA
and northwest MO over the next several hours. This energy is
expected to begin interacting with a gradually increasing
south-southwest low-level jet and proximity of both a weak
stationary front and a nearby outflow boundary which will
facilitate developing and expanding areas of heavy showers and
thunderstorms.

The latest RAP analysis shows a rather substantial pool of
instability over far eastern KS and especially central MO with
MUCAPE values of 2000 to 3000 J/kg. Additionally, the column
across much of the region is very moist with PWs of 2.25+ inches
noted. In fact, the 00Z RAOB at Topeka, KS depicted an
impressively high PW of 2.34 inches for a new daily record!

Extremely heavy rainfall rates are expected with the evolving
clusters and/or bands of convection that materialize overnight and
going into the early morning hours. The convection will have some
support from weak right-entrance region upper jet dynamics in
close proximity to the aforementioned surface boundaries, and the
activity should tend to become more aligned with the deeper layer
steering flow which will promote concerns for cell-training.

Overall, the environment seems conducive for rainfall rates that
could easily reach 2 to 4 inches/hour with the stronger storms,
and with cell-training concerns associated with some of these
convective bands, the rainfall totals at least by dawn may be
capable of reaching 4 to 6+ inches. While there are some
latitudinal differences between the 00Z HREF and the 18Z REFS
solutions, both hires CAM ensemble suites suggest potential for
locally high-end rainfall.

Given the expected rainfall potential and already locally
moist/wet antecedent conditions, scattered to numerous areas of
flash flooding are expected to materialize over the next several
hours. This will include a threat for significant and dangerous
urban flash flooding.

Orrison

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

ATTN...WFO...DMX...DVN...EAX...ICT...ILX...LOT...LSX...OAX...
TOP...

ATTN...RFC...KRF...MSR...TUA...NWC...

LAT...LON   41889005 41698895 41178848 40538846 40028920
            39839096 39509247 39019376 38139561 38229662
            38949675 39729606 40659457 41109350 41539230
            41799118