Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
858 PM EDT Fri Jun 12 2026
Day 2
Valid 12Z Sat Jun 13 2026 - 12Z Sun Jun 14 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN KANSAS AND SOUTHWEST MISSOURI...

...Central Plains to Mid-Mississippi Valley...

20Z Update: In coordination with the local WFO's across eastern
Kansas into Missouri, a Moderate Risk was issued for the D2 period
with emphasis across eastern Kansas into southwestern Missouri.
Deep moist environment will preclude the arrival of a prominent
shortwave ejecting into the Central Plains, making headway into the
mid-Mississippi Valley on Saturday afternoon and evening.
Instability gradient will be present across northern MO into Iowa
as a cold front begins to slowly press south with the guide of a
potent shortwave trough dropping out of Canada. This is the making
of an increasingly convergent low to mid-level setup within a very
favorable environment across the nation's mid-section.

Instability across eastern KS into MO will be quite robust with
model forecast MUCAPE along and east of I-35 into the 3500-5000
J/kg range by the time we reach peak diurnal heating. Coupled with
a deep moisture pool in the column, any convective development will
comprise of significant rainfall rates as noted via elevated hourly
and 3-hourly prob fields within the latest 12z HREF. Deterministic
output from various CAMs indicate rates between 2-3"/hr with likely
higher intra-hour rates exceeding 4" at times, especially as you
get further south into southeastern KS and southern MO where
instability will be maximized. QPF forecasts are consistent for
2-4" totals across the area south of Topeka down into the
Joplin/Springfield region of southwestern MO. Kansas City at this
time on the edge of the potential with a split in guidance on where
the heaviest precip will reside for the northern and northeast
periphery of any established maxima. Considering such a close
proximity to the max, and the D2 error in convective forecasting
still a concern, there's potential that the urban center can get
into some of the heavy precip as it materializes on Saturday
evening. With a Flood Watch issued over the metro and surrounds,
decided to include the city in the MDT risk to maintain consistent
messaging and signaling a heightened threat compared to normal.

A high-end SLGT is forecast for much of the remainder of Missouri
not encompassed within the MDT risk. There could very well be an
initial round of thunderstorms in the morning across southern MO in
conjunction to the shortwave moving across the area as referenced
in the D1 update. Any rainfall occurring would be a priming
scenario for what would transpire later as the cold front to the
north begins pushing south with a strong low-level convergence
pattern taking shape over the mid-Mississippi Valley. The area of
greatest concern, outside the MDT risk, is likely across
northeastern MO where recent rainfall over the past 72hrs have led
to significant flash flooding over portions of the area allowing
for highly compromised soils and swollen streams and creek beds
located in the area. Local FFG's in the 1/3/6 hour thresholds
continue to run much lower than normal with most of the thresholds
between 1-2" for either temporal range meaning any heavy convection
will be susceptible to flash flood prospects. As of now, the saving
grace for areas north of I-70 will be a majority of the precip will
be due to the frontal progression and any convection should be more
progressive in the grand scheme. This typically negates significant
flooding prospects as rainfall will only last for so long before it
moves away and we see a de-escalation of hydrologic impacts. In any
case, the threat is still elevated across much of the mid-
Mississippi Valley, so the period will bear watching for any short
term upgrade potential if trends allow.

...Midwest...

20Z Update: A strong cold front will migrate through the region
allowing for convective initiation over the Central Midwest into
the western Great Lakes, overlapping areas that have been hit
recently with periods of heavy rainfall. The highest potential is
across southern and eastern IA into northern IL where significant
rains have impacted area FFG's considerably over the past 72hrs
meaning chances for flash flooding are easier to attain.
Progressive nature of precip is the reason this area is just
outside the more significant rainfall prospects, however
environmental conditions are still favorable over the area with
deep moisture pooled as far north as I-80 for the setup. As the
front moves out of the area, drier air will advect into the region
in its wake ending the threat for the rest of the forecast period.
Widespread 1-3" with local to 4" is forecast in this area of the
CONUS, certainly enough to cause scattered flash flood threats as
the pattern evolves when you couple with the lower FFG's in place.
A broad SLGT risk is forecast for the potential.

Kleebauer


Day 2 threat area: www.wpc.ncep.noaa.gov/qpf/98epoints.txt