237
FXUS63 KDMX 182343
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
543 PM CST Sun Jan 18 2026

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

.KEY MESSAGES...

- Gusty winds, light snow and blowing/drifting snow will cause
  reduced visibilities through this afternoon and evening,
  especially over central and northern Iowa.

- Frigid wind chills develop tonight, with values dropping to
  the teens below zero south to twenties below zero north
  through Monday morning.

- Cooler temperatures continue Monday, then warm back towards
  normal by Tuesday. Snow chances (40-50%) return to northern
  and northwestern Iowa Tuesday night into Wednesday.

&&

.DISCUSSION...
Issued at 207 PM CST Sun Jan 18 2026

Our cold front and snowfall has begun to make it`s way through the
area early this afternoon. Winds are steadily flipping to
northwesterly and increasing over the western half of the state,
with gusts up to 40 mph already being observed in the northwest. An
area of light snow is accompanying this front, leading to
visibilities generally around 1 to 2 miles. With the winds slightly
lagging the snowfall, significant visibility reductions have been
avoided thus far and snow has been light enough to keep road
conditions from worsening. Farther upstream, satellite and radar
imagery in Minnesota and the Dakotas indicate streaks of HCRs
accompanying the increasing winds and cold air advection. While not
persistent, the combination of falling snow from the HCRs and strong
winds have dropped visibilities under a mile, with occasional 1/4
mile visibilities in southwest Minnesota. This will be the next
hazard to watch for, as these snow showers are beginning to make
their way into northwest Iowa. Sudden visibility reductions may
occur while driving in northern Iowa this afternoon and evening.
Likewise, gusty winds over a cold, fluffy snowpack will likely stir
up some drifting snow through the afternoon and evening. For these
reasons, the Winter Weather Advisory remains unchanged and in
effect until 9 pm this evening.

Temperatures will plummet and winds will diminish but remain breezy
behind the cold front tonight. Wind chills overnight will fall into
the twenties below zero north to teens below zero south through
Monday morning, making for a frigid start to the work week. The Cold
Weather Advisory remains in place for much of northern, central and
southeastern Iowa through noon on Monday. Winds will be light to
breezy through the day on Monday, steadily becoming more westerly.
Temperatures will warm some during the day, but highs still only
reach the single digits above zero north and mid teens south with
wind chills on either side of zero, depending where you are in the
state.

A weak shortwave will pass through the state later Monday into early
Tuesday, bringing increased cloud cover aloft but remaining dry at
the surface. Surface high pressure will fill in by Tuesday morning,
with a more southerly return flow developing through mid-day.
The southwesterly flow will help to boost temperatures back into
the 20s and 30s on Tuesday.

Our next chance for precipitation returns to Iowa on Tuesday night
into Wednesday as another weak shortwave follows quickly behind the
previous. This wave will have a bit more moisture with it as the
surface low passes directly overhead, generating a band of light
snowfall from west to east through northern Iowa and/or southern
Minnesota. There are still some discrepancies in guidance on how
this low pressure will evolve as it tracks eastward, although
there is fairly good agreement that snow will occur with this
wave. The main sticking point will be where the main band sets
up and how intense it will be, with deterministic models placing
the heaviest band on either side of the Iowa/Minnesota border.
Ensemble solutions have started to narrow in on this as well,
with the grand ensemble probabilities for 0.05" of QPF in 24 hrs
around 60 to 70% in northern and northwest Iowa, then values
tapering off farther south. Exact snow amounts are still
uncertain, but a higher-than-climo snow to liquid ratio (climo
for Iowa is around 13:1) likely with the cold profiles, so it
will be worth watching how the QPF trends shake out. Regardless,
this is still a few days out, so will continue to refine the
details through the coming days and as more data becomes
available. Breezy conditions then develop again on Wednesday
behind the system.

Yet another wave looks to move through toward the second half of
this week, which will bring another plume of colder air down into
the state, bringing another bout of very cold temperatures through
the weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 543 PM CST Sun Jan 18 2026

Aviation concerns are in the first half of the period as strong,
gusty winds from the northwest are causing significant blowing
snow in isolated locations of north central Iowa, including MCW
and to a lesser degree ALO. These conditions will improve as
winds diminish gradually overnight into Monday. Farther south
at DSM and OTM, a few areas of light snow are moving
southeastward and have include TEMPO as these pass through the
area. Have been pessimistic on improvement with shallow clouds
expected to continue MVFR despite guidance showing faster
improvement. Therefore, have delayed return to VFR until late
this evening if not sometime Monday morning.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 9 PM CST this evening for
IAZ004>007-015>017-023>028-033>039-048>050.
Cold Weather Advisory from 9 PM this evening to noon CST
Monday for IAZ004>007-015>017-023>028-033>039-045>050-061-062.
Cold Weather Advisory from 1 AM to noon CST Monday for
IAZ058>060-072>075-083>086-095>097.

&&

$$

DISCUSSION...Dodson
AVIATION...Ansorge