Flash Flood Guidance
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Issued by NWS
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836
AWUS01 KWNH 141151
FFGMPD
MOZ000-IAZ000-KSZ000-NEZ000-141700-
Mesoscale Precipitation Discussion 1281
NWS Weather Prediction Center College Park MD
750 AM EDT Mon Sep 14 2026
Areas affected...Southwest Iowa...Southeast NEB...Northeast
Kansas...Northwest Missouri...
Concerning...Heavy rainfall...Flash flooding possible
Valid 141150Z - 141700Z
SUMMARY...Flash flooding potential continues as focus shifts
southward to more favorable repeating/training axis for a few more
hours. Additional 2-3" totals possible through late morning.
DISCUSSION...GOES-E 10.3um shows the NNW to SSE oriented
warm-advective convection has been showing a general warming trend
as diurnal peak has passed and the 800-700mb warm-advection
reduces as the LLJ slacks as the driving shortwave moves more
northeast. However, the southern flank of the convective
complex, likely driven by a eastward surface to boundary layer
reinforcement helped to steepen isentropic ascent plane combined
with outflow from the elevated cells northward. As such, there
remains a solid east to west convective line, with a lower LFC
from Livingston to Daviess to Andrew county in NW MO across to
Marshall county KS. VWP shows solid veering (SE-SW) in the
925-850mb layer at 25-45kts through depth to intersect this
boundary providing that lower convective initiation, as well as,
unobstructed ascent of an axis of conditionally unstable air with
MUCAPE around 1000-1250 J/kg. Given solid available sfc to 700mb
moisture (per CIRA LPW), cells will continue to be capable of
1.75"/hr but reduce with further slacking of LLJ winds over the
next few hours. The orientation of the line from west to east
and weak WSW to ENE steering flow should allow for
repeating/training profiles for localized streak or two of
additional 2-3". Given this is close to or over areas already
affected, flash flooding potential is likely to continue and
possible to expand in a few adjacent areas in NW MO.
Additionally, the eastern edge of the LLJ axis intersects the
upwind edge so additional TCu and CBs are developing across NE KS
into SE NEB; though 3.9um SWIR suggests the ascent plane is
starting to be more flat across E NEB. Still, any additional
upstream redevelopment across areas already heavily affected could
maintain ongoing flooding conditions through the Missouri River
Valley. As an overall pattern, this evolution has been closest to
the the 00z ARW solution though a hour or so faster, given this, a
16-17z ending time frame seems more plausible than other solutions
that have been continuously trying to end the event too quickly in
line with typical early morning WAA known biases.
Gallina
...Please see www.wpc.ncep.noaa.gov for graphic product...
ATTN...WFO...DMX...EAX...OAX...TOP...
ATTN...RFC...KRF...MSR...NWC...
LAT...LON 42149546 41859433 40369275 39569280 39269413
39319552 39539635 39989664 40609652 41339622
41949615