105
FXUS63 KDMX 081139
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
539 AM CST Mon Dec 8 2025

 ...Updated for the 12z Aviation Discussion...

.KEY MESSAGES...

- Warming trend to start the week, reaching the upper 30s to
  low 40s by Tuesday.

- Strong cold front on Tuesday night will bring gusty winds
  35-45+ mph overnight into Wednesday morning. Wintry mix is
  also possible with frontal passage.

- Active pattern continues through the rest of the week with
  additional snow chances and colder air returning.

&&

.DISCUSSION...
Issued at 239 AM CST Mon Dec 8 2025

A weak PV anomaly, noted in GOES-East water vapor imagery, has
resulted in patchy light snow across mainly northern into central
Iowa overnight. Radar depiction is more robust than and snow that is
reaching the ground in actuality with dry air in place. As this
continues east thorugh the early morning hours expect coverage
to continue to decrease. Expectation for a dusting of snow at
most for locations across northern Iowa. There is a signal in
model soundings that ice introduction will be lost as the column
de-saturates through the morning which could result in a brief
period of light freezing drizzle. This has not materialized yet
this morning and expect that with dry air in place any further
de-saturation would result in precipitation stopping altogether
rather than precipitation type swapping from snow to freezing
drizzle. Even so with low likelihood, will keep an eye on
conditions through the morning hours as freezing drizzle can be
hazardous, especially for the morning commute.

A shortwave will pass north of the area later today and into
Tuesday, and while moisture will stay north of the area, warm air
advection into the area will send temperatures through the upper 30s
to low 40s on Tuesday. Despite the strong warm air advection into
the area on Tuesday, the snow pack is likely to impact temperatures
on Tuesday, especially across northern to central Iowa where the
pack is deepest. Dewpoints are in the low to mid 30s in northern to
central Iowa which may create a ceiling for the warming potential. A
second, robust shortwave will pass across the area later Tuesday
into Wednesday. This one will bring chances for rain, transitioning
to a wintry mix, to northern and eastern Iowa. More notably, there
will be strong cold air advection and subsidence behind the system
overnight into Wednesday morning. This will result in windy
conditions. Model soundings show 40-55+ kts through the mixed layer
and expect we will need at least an advisory for these winds. Winds
were nudged up on this shift, but expect further increases will be
needed. Lastly, soundings continue to show some instability with
the gusty winds overnight into Wednesday morning, which could
result in more convective driven snow showers (HCRs/snow squall
potential).

Temperatures are colder Wednesday into the end of the week
behind the system. The pattern remains active with additional
snow chances Thursday and reinforcing cold into the weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 539 AM CST Mon Dec 8 2025

Stratus blankets Iowa this morning, ranging from VFR in the east
to MVFR/IFR in the north and west. Stratus will remain in place
all day with some lowering through the morning and afternoon.
Wind will be light out of the south today, shifting overnight
to out of the west by Tuesday morning. Northern sites
KFOD/KALO/KMCW will see MVFR to IFR stratus through the TAF
period, though KDSM should improve to VFR after 00z and KOTM is
expected to remain VFR.

&&

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

&&

$$

DISCUSSION...Hagenhoff
AVIATION...Hagenhoff