281 

AWUS01 KWNH 181003

FFGMPD

MOZ000-KSZ000-181500-



Mesoscale Precipitation Discussion 0182

NWS Weather Prediction Center College Park MD

602 AM EDT Mon May 18 2026



Areas affected...eastern KS into western/southwestern MO



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



Valid 181000Z - 181500Z



Summary...While some uncertainty remains, concerns are increasing

for possible flash flooding later this morning over

western/southwestern MO into portions of eastern KS. Hourly

rainfall of 1 to 2+ inches and 3 to 4 inches in 3 hours will be

possible through 15Z (10 AM CDT).



Discussion...0930Z radar imagery and surface observations showed

that the southwestern end of an elongated outflow boundary has

stalled over central KS, while it continued to steadily advance

southeastward through MO. Showers and thunderstorms continued to

develop on the cool side of the boundary over eastern KS and

central MO as a strong southerly low level jet (LLJ) over KS/OK/MO

overruns the well-defined boundary. While the LLJ has weakened and

veered some over the central KS/OK border (less favorable angle to

the outflow boundary), some recent strengthening was observed at

the KINX VAD wind at 09Z to over 70 kt (but it as backed off a bit

since then). Meanwhile, disorganized shower/thunderstorm activity

has picked up over the past 45 minutes over southwestern MO,

perhaps aided by lift ahead of a vort max observed lifting NNE

from the southern OK/AR border on water vapor imagery. Steep

mid-level lapse rates of 7 to 8+ C/km were contributing to sizable

MUCAPE over 2000 J/kg from southeastern KS into central MO. Aloft,

flow remained highly diffluent between the polar and sub-tropical

jet streams aloft.



While recent runs of the HRRR and RRFS have struggled to properly

handle the outflow boundary's southward propagation, they have

been consistent with an uptick in convective vigor over the next

3-6 hours, favoring the southwestern flank of the outflow near the

southern KS/MO border. It is here that the LLJ (though weakening)

will focus from northeastern OK into southwestern MO into and atop

the KS/MO outflow boundary. The environment will favor training

with 1 to 2+ inches of rain in an hour and potential for 3 to 4

inches of rain in 3 hours or less. While flash flood guidance is

quite high over much of the region, some limited/isolated flash

flood potential will exist through 15Z and perhaps continue into

the early afternoon.



Otto



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



ATTN...WFO...EAX...ICT...LSX...SGF...TOP...



ATTN...RFC...KRF...ORN...TUA...NWC...



LAT...LON   39039508 39009309 38669248 38179217 37279244 

            36919354 37219542 37739683 37789774 38199784 

            38789717 38949649