926
FXUS63 KDMX 150014
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
714 PM CDT Sat Jun 14 2025

 ...Updated for the 00z Aviation Discussion...

.KEY MESSAGES...

- Isolated to scattered storms this afternoon into the overnight
  and again on Sunday. A few strong to severe storms are
  possible with gusty winds and small hail the primary threats.
  A few funnel clouds are also possible this afternoon into
  early evening mainly north.

- High confidence in stormy pattern through next week. While
  lacking specifics such as timing, location, and hazards, one
  and likely more than one round of strong to severe storms will
  be possible over the state in this period.

- Increasing confidence in heavy rainfall next week that could
  lead to flash flooding and/or river flooding later in the
  week. Similar to above, the location is not clear, but chances
  will increase if rain can repeat over the same basins and as
  time goes on in the week.

- Staying warm and humid most days through late next week.

&&

.DISCUSSION...
Issued at 342 PM CDT Sat Jun 14 2025

Highly active pattern today through much of next week as has been
discussed in the last several discussions. Lingering warm front that
has been hanging out nearby for many days now is noted over northern
Iowa with clouds bubbling in much of the area south of the boundary
through the daytime today. As of early afternoon, convection has
begun to develop along this front as expected with a warm, moist
airmass to the south as temperatures have warmed well into the 80s,
and even low 90s in some cases, with widespread dew points in the
60s to near 70. Meanwhile, Estherville north of the boundary, is
only in the 70s. Although shear remains quite weak through the
profile, MLCAPEs have reached towards 2000 J/kg per SPC mesoanalysis
which is more than plenty to kick off some storms which have the
potential to become strong to even severe in north central Iowa as
they develop before these storms drift south into portions of
central Iowa into the rest of the evening. With the marginal shear,
storms will struggle to remain organized with gusty winds the
primary threat from a combination of collapsing storms and gusty &
erratic storm outflow, but some small hail is certainly possible in
the better updrafts. Additionally, with the frontal placement and
associated vorticity interacting with the surface-3km CAPE,
conditions are favorable for funnel cloud development this afternoon
into early evening. This is most true in northeast to north central
Iowa per objective analysis but is also where the non-supercell
tornado (NST) parameter is highest per SPC mesoanalysis and RAP
projected NST parameters through the afternoon. Any funnels that do
form are expected to be brief and only drop a few hundred feet with
high enough bases (LCLs largely near to over 1000 m) that a brief
tornado is not expected, but conditions will be monitored
closely.

Although the initial afternoon development will largely diminish by
mid to late evening, additional development is forecasted in
northern Iowa late tonight into portions of the overnight as the
pressure trough slides through largely still along the lingering
boundary. There are varying degrees of how long this activity will
last in CAMs and how robust, but a few hundred J/kg of MUCAPE
may still be present enough for some rumbles of thunder, but not
expected any severe weather overnight with shear still quite
weak and much of the instability used up this afternoon/evening
and no great LLJ placement to help enhance activity further.
However, the boundary doesn`t go much of anywhere Sunday with
additional thunderstorm development expected in northern Iowa by
mid to late morning as instability increases with activity
drifting east and south with time through the afternoon and
evening hours. Although the better parameter space remains to
the west could see some more strong to even marginally severe
storms develop, not too dissimilar from today, with gusty winds
and small hail. This activity largely ends again by mid to late
evening Sunday with a short break per current CAMs though will
need to watch a potential MCS coming out of NE that the global
models in some cases still bring into at least portions of the
area, while the CAMs have it diminish before it gets to the
Missouri River. Will certainly be watching this threat closely.
With expected convection at times, did lower highs slightly
Sunday, though conditions will still be warm and largely in the
80s.

Few updates from the 06.13.25 afternoon discussion with regards to
next week as the upper level pattern continues to remain supportive
for several ridge riding waves bringing several rounds of storms
through the week. Instability and shear both become increasingly
more favorable by Tuesday with pwats 1-2"+ at various times and
locations through much of the week promoting efficient rainfall when
combined with deep, warm cloud depths. Hydro concerns certainly
increase with time after subsequent rounds of rain and storms over
multiple days, with flash flooding concerns heightened over areas
that see repeated storms. In addition, several rounds of storms will
increase rain in the rivers and could lead to at least increased
flows on area rivers if not some possible river flooding by the
end of the week. On the severe side of things, location,
placement, and timing remain a bit more uncertain, but much of
the area is in a SPC Day 3 Level 1 with the far north to
northwest in a level 2 (of 5 in both cases) risk for Monday and
a 15% draped across much of southern Iowa in the SPC Day 4 for
Tuesday with the 15% for Wednesday just off to the east per the
overnight severe weather outlooks. Details will continue to be
fine-tuned but certainly an active period with several rounds of
storms and rain that will need to be watched closely.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 712 PM CDT Sat Jun 14 2025

Scattered showers and storms continue to drop southward across
central Iowa this evening. Given the isolated nature of these
storms, have kept PROB30 mentions at KALO and KDSM over at least
the next few hours. Otherwise should see activity waning through
the evening, though another wave moving into northern Iowa will
bring returning chances for showers and storms. Confidence on
exact timing and coverage remains low at this time, but have at
least PROB30 mentions to highlight the potential and will adjust
as needed. This activity may gradually reach into central Iowa
but uncertainty on coverage is higher at this time and will
continue to monitor. MVFR ceilings are also expected across the
far north through the morning.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...05
AVIATION...Bury