917
FXUS63 KDMX 250355
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1055 PM CDT Thu Sep 24 2026

 ...Updated for the 06z Aviation Discussion...

.KEY MESSAGES...

- Periods or rain with a few embedded thunderstorms through
  early Sunday. Total rainfall amounts of 1 to 2 inches are
  possible over parts of central and southwest Iowa.

- Another strong storm system expected Tuesday and Tuesday
  night. Thunderstorms with heavy rainfall are possible.

- Highs generally in the 60s and low 70s.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 251 PM CDT Thu Sep 24 2026

High pressure ridging remains over eastern Iowa this afternoon while
return flow has arrived over western Iowa. A stratus layer of clouds
is occupying parts of eastern Iowa despite the high pressure
ridging. Rain has increased over western and parts of north central
Iowa this afternoon in response to the moisture return. Cloud bases
are beginning to respond with cigs near 1 kft over far northwest as
the top-down saturation occurs. The light rain will expand into
central Iowa tonight though with gradual diminishing returns as it
encounters dryer air to the east. A short wave lifting through the
region tonight into tomorrow morning will result in a more
widespread area of precipitation moving into southwest to central
Iowa. Some convective elements are possible with this precipitation
but weak instability and weak mid-level lapse rates will keep
lightning to a minimum. Precipitation amounts of one half to one
inch could occur over parts of the southwest forecast area by early
Friday afternoon. The precipitation will diminish in the afternoon
and evening before the next round arrives.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Issued at 251 PM CDT Thu Sep 24 2026

Another short wave will arrive Friday night into Saturday as the
moisture plume continues to slowly track eastward resulting in
another round of widespread precipitation. More instability is
possible over western Iowa on Saturday afternoon which could result
in more convective activity but again, the threat for strong storms
is low. Dryer air will arrive from west to east late Saturday night
into Sunday though mostly cloudy skies are expected to persist.
Monday will be mostly dry and slightly warmer with highs in the 60s
to near 70. Another strong short wave will arrive Tuesday and
Tuesday night. PWAT values will approach 2 inches and conditions
will be favorable for rainfall amounts of 1-2 inches. Note, Des
Moines is currently a little over 2 inches from the September record
for precipitation. This will be approached with the system this
weekend and the one early to mid next week.

For Wed into the end of the week, models are taking turns trying to
ingest the Pacific Hurricane Palo into southwest flow as a strong
upper level low approaches the Four Corners region. There remains a
lot of uncertainty here regarding this ingestion and the overall
evolution of the upper level low but a slower progression of
everything may lead to more wet weather for Iowa.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1054 PM CDT Thu Sep 24 2026

While rain is tapering off in most areas, another wave will be
entering southwest Iowa at the start of the TAF period and will
lift across much of the state through the morning. Highest
confidence to see showers will be KOTM and KDSM, with lowering
probabilities further north given uncertainty in northern
extent, so have used PROB30 and TEMPO groups accordingly. With
this rain will also include lowering ceilings, with increasing
coverage of MVFR/IFR conditions throughout the day. Winds out of
the southeast will increase through the morning, with gusts by
late morning to afternoon up to 15-20 knots.

&&

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

&&

$$

SHORT TERM...Donavon
LONG TERM...Donavon
AVIATION...Bury