807
FXUS63 KDMX 061719
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1219 PM CDT Mon Oct 6 2025

 ...Updated for the 18z Aviation Discussion...

.KEY MESSAGES...

- Scattered showers mainly continue on and off today into
  central and southern Iowa, with a few storms possible mainly
  southeast by the afternoon, though the severe potential is low
  at this time

- Dry conditions return through Tuesday morning, with more
  seasonal temperatures in the 60s.

- Temperatures gradually warm back into the 70s later in the week.

&&

.UPDATE...
Issued at 353 AM CDT Mon Oct 6 2025

Radar analysis early this morning depicts a rather broken line of
mostly stratiform showers over southwestern into northeastern Iowa,
along with a few isolated weak thunderstorms. All of this activity
is occurring near and behind the slow moving frontal boundary that
continues to drop through the state, oriented in a line roughly from
Grinnell through Lamoni as of 3am. This front is easily noticeable
from the temperature difference from northwest to southeast, with
values in the upper 40s to 50s behind the front and values in the
mid to upper 60s ahead. General trends per CAM guidance show this
front slowly creeping southeast this morning, with showers
continuing to lift east/northeast this morning, before another
energy impulse tracks eastward into the state by late morning
through the afternoon, bringing additional scattered showers across
portions of central to southern Iowa. Though the front is generally
expected to exit the state by early afternoon, a lag in the cooler
air will result in warmer temperatures remaining over southeast Iowa
for much of the day yet, with highs reaching into the 70s while the
remainder of the state sees much lower values in the upper 50s to
low 60s. In terms of the potential for storms for the rest of today,
instability will be limited across the majority of the state given
cooler temps/dewpoints, keeping concerns for much in the way of
storms minimal, though some occasional bouts of lightning cannot be
ruled out. Over southeast Iowa where the warmer temperatures and
dewpoints are located, higher instability amounts around 500+ J/kg
with favorable shear could produce a few storms in this area by the
afternoon into the evening, though the better parameter space will
be oriented further east and south out of Iowa, so the potential
looks fairly low for severe weather but cannot rule out a strong
storm. The general thunder per SPC guidance is reasonable
considering the details discussed above. Regarding rainfall, a
complete washout is not expected given the scattered nature with
breaks of rain expected at times today. Additional rainfall amounts
of 1-1.5 inches are expected, with highest accumulations over
southwest Iowa where a few isolated pockets of 2`` could occur into
early Tuesday. Despite the 1-2+ inches that fell from Cass county up
through Butler county yesterday, these additional amounts generally
falling roughly over the same area are not expected to lead to any
flooding concerns, as the previously dry soils have been able to
take the rainfall well, which ended the long period of dry weather
that much of Iowa experienced.

Lingering showers continue into Tuesday, with dry conditions
returning by mid-morning per general model consensus, with northerly
flow spreading across the entire state. High pressure drops into the
region, with dry conditions expected for the rest of the day paired
with more seasonal temperatures as highs are expected in the 60s
across Iowa.

&&

.DISCUSSION...
Issued at 221 PM CDT Sun Oct 5 2025

Winds remain breezy out of the southwest today ahead of the cool
front that has reached northwest Iowa early this afternoon. Wind
have generally gusted 25-35 mph so far today with a few isolated
gusts near 40 mph. At the same time the surface boundary has reached
northwest Iowa with spotty reflectivity returns on radar. Much of
this is not reaching the ground with significant dry air to battle
initially. Cloud cover has helped keep afternoon temperatures a
few degrees cooler than Saturday and winds are marginally
reduced as well, helping to reduce potential cropland fire
concerns. Even so, caution should be used with fires or anything
that may produce sparks the rest of today. As upper level
support arrives later this afternoon and evening expect to
increasing saturation thorugh the column and more widespread
precipitation along the front. Instability is limited with <500
J/kg MLCAPE and best 0-6km shear lag behind the instability
axis. This will help to limit severe potential, however with dry
profiles initially any early convection may produce gusty
winds.

The front slowly sinks southeast overnight and through the day on
Monday. CAMs today have come into much better agreement today with
the timing and placement of precipitation passing across Iowa,
becoming more widespread on Monday before exiting southeast on
Tuesday morning. Northwest Iowa will miss out on much of the QPF as
the boundary passes before saturating, but much of central to
east/southeast Iowa will see 1+ inches of rain with a band of 2-3+
inches likely from southwest to central Iowa. This rain is falling
across areas (most of Iowa) that have not seen much in the way of
precipitation for several weeks, so despite amounts of 2-3+"
possible this will fall over a prolonged period over very dry soils
with very little chance for any hydrologic concerns.

High pressure build across the area on Tuesday, pushing the boundary
southeast of the area. Temperatures come down 20+ degrees the the
frontal passage with highs in the 60s to start the week, warming
back through the 70s by late week. A couple shortwave may move
across the area mid to late week, however model continue to struggle
with timing so confidence is lower at this time.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1216 PM CDT Mon Oct 6 2025

A broad area of showers is moving across Iowa this afternoon. In
addition, MVFR to IFR stratus is situated along and southeast of
a KDSM-KALO line and just moving into KOTM to start the period.
The showers and clouds will be gradually moving southeast
this afternoon and evening with conditions improving from the
northwest. Clearing will begin to occur by Tuesday morning. The
wind will remain light out of the north at 10 kts or less.

&&

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

&&

$$

UPDATE...Bury
DISCUSSION...Hagenhoff
AVIATION...Donavon