369
FXUS63 KDMX 311950
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
250 PM CDT Sat Oct 31 2026

.KEY MESSAGES...

- Rain lifting by the end of the night with dry conditions
  remaining Sunday.

- Rain returns Sunday night. Marginal Risk for severe weather
  Monday afternoon.

- Rain remains likely through at least Wednesday.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 248 PM CDT Sat Oct 31 2026

After a dreary start to the day, rain is starting to lighten up
across the state this afternoon. Some sprinkles could be possible
through the evening, but the bulk of today`s rain has already
fallen. Height rises on the exiting half of the shortwave will
eliminate most all of the rain on Sunday. Some peaks of sun will be
possible in the south Sunday afternoon and highs will return to the
60s area-wide. Rain returns Sunday night as moisture advection
increases ahead of a large trough in the western US.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 248 PM CDT Sat Oct 31 2026

The trough has closed northern and southern stream components
to it, which look to merge together over the region Monday
night. Ahead of then, the southern feature will mature as it
ejects into the Plains. The midlevel reflection of the jet will
round the trough base and cover the warm sector Monday
afternoon. 700mb temperatures have trended warmer in southern
Iowa, so lapse rates are closer to 7 C/km. MUCAPE values could
surpass 500 J/kg in far southern Iowa. A line of storms will
form along the cold front, but its threats will depend on how
much clearing can take place ahead of its arrival. REFS ensemble
soundings and hodographs have favorable shear parameters for
damaging winds and tornadoes, but are at the mercy of the lower
thermal profile. There is not much spread in the PBL temperature
values, which struggle to mix in most all ensemble members.
Without near-surface instability, the threat will be mainly
isolated damaging winds.

Another notable trend is the timing of the front arriving in Iowa.
This is because the two aforementioned components of the trough will
be merging together, causing the resultant closed low to stall. The
delayed arrival means severe weather chances are lower, since storms
would be arriving after dark. The slowed movement then increases the
rainfall amounts, as the front will utilize the 1.5" PWATs and drop
1-2" in southern Iowa. Something else we`ll need to watch is storm
potential in eastern Iowa on Tuesday afternoon due to the front`s
late exit. That said, the thermal profile looks less impressive on
Tuesday, by comparison. Cooler temperatures will advect in on the
backside. Precipitation chances linger through much of the week due
to the TROWAL of the system.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1231 PM CDT Sat Oct 31 2026

Rain and low cigs will focus north in the short term. Last push
of rain is arriving at KDSM at the beginning of the TAF period
and the chance of sub-VFR decreases after that rain exits. Light
southeast flow prevails in the planning period with stratus
potentially lingering over northern Iowa. (hence SCT012 mention
at KMCW) Some sprinkles will last through 06z, but its not
expected to be impactful.

&&

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

&&

$$

SHORT TERM...Jimenez
LONG TERM...Jimenez
AVIATION...Jimenez