168
FXUS63 KDMX 221124
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
524 AM CST Thu Jan 22 2026

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

.KEY MESSAGES...

- Breezy again today into tonight, especially north and
  northeast where blowing snow will occur once again and may
  produce additional travel impacts.

- Very cold temperatures will surge in from the northwest later
  today, with wind chills reaching dangerously low values of
  30-40 below zero across most of Iowa by Friday morning. An
  Extreme Cold Warning is now in effect for the entire area
  overnight.

- Cold weather will persist through the weekend, but may not be
  quite as intense as the first 24 hours, therefore an Extreme
  Cold Watch remains in effect from noon Friday until noon
  Saturday. Chances for light snow over the weekend have
  increased to 20-50% at times, with the highest chances near
  the Missouri border, but any accumulations will be light and
  without significant blowing snow as winds will be lighter by
  that time.

&&

.DISCUSSION...
Issued at 217 AM CST Thu Jan 22 2026

A surface high pressure area is sliding by over Kansas and
Missouri early this morning, with diminished winds and partly
cloudy skies in our forecast area. A few flurries have been
observed over southern Minnesota in association with a mid-level
impulse moving by to our north, but these are not expected to
appreciably impact our counties this morning. Meanwhile, a
large Arctic high pressure area is centered over southwestern
Canada and has already begun to build down into the Dakotas
overnight and will continue to do so today. The leading edge of
this push of colder air will act as an effective cold front,
traversing the CWA from northwest to southeast during the day.
As it does so, a ribbon of forcing will scoot eastward across
central and southern Iowa this afternoon and some short-range
models are generating light snow accordingly. However, most of
the model suite has been overdone on snowfall the last few days
when soundings show a lack of moisture and that is the case
again today. With the forcing being so transient and a dry
appearance to the soundings, have opted to add flurries central
and south but with no measurable accumulation. Of potentially
greater impact is that as the cold airmass flows in later today
and tonight, it will bring breezy conditions once again
especially in our northern and northeastern counties where
blowing snow has already been an issue. Forecast soundings show
some potential for approximately 30 KT gusts around EST, MCW,
and ALO for a couple hours this afternoon, and even overnight
with strong cold air advection promoting mixing the gusts should
remain in the 20-25 KT range across much of the area after
dark. Have increased forecast winds and expanded mention of
blowing snow accordingly, with renewed travel impacts expected
in areas that still have snow on the ground from yesterday and
earlier and are still struggling to clear the blowing snow from
yesterday.

As temperatures plummet tonight and north northwest breezes are
sustained, wind chills will rapidly fall to dangerous levels
across Iowa. Have upgraded the Extreme Cold Watch to a Warning
tonight through Friday morning, and moved the start time a few
hours earlier in our northern counties where wind chills will
already fall into the 30-40 below zero range before midnight. By
around sunrise Friday wind chill values will be -30 or lower
across nearly our entire service area, excepting perhaps a few
counties in the far south and southwest. Slow improvement is
then expected during the day as winds continue to diminish and
temperatures rise slowly, but it will still remain very cold.

During the day Friday, a very well-advertised and expansive
winter storm will take shape across the southern U.S., where an
impressive breadth of warnings, watches, and advisories are in
effect for the coming weekend. For the last several days most
indications have been that the large precipitation shield will
remain just south of Iowa, aided by the large high pressure area
overhead. However, in the last 24 hours several model runs have
resolved the phasing of the 500 MB trough responsible for this
system differently, and are now allowing for the northern
fringes of the clouds and precipitation to enter our area to
varying degrees. Between Friday night and Saturday night nearly
all models now have at least a little QPF in southern Iowa, and
some runs bring it up to about Highway 20 or so. However, given
persistence from earlier forecast trends and the proximity of
the large high pressure area and associated dry air entrainment,
it is difficult to have much confidence in these wetter
solutions, especially in the first part of the event on Friday
night and Saturday. After that the Arctic high pressure area
will retreat eastward and conditions may be a bit more conducive
to light snow, mainly in our south, but by then the brunt of
the southern U.S. storm will be moving away to the east. Given
this combination of factors, have maintained low to medium
(20-50%) POPs across about the southern half of our forecast
area around Saturday, highest near the Missouri border, but kept
the north dry. This scenario also has impacts on the duration
of the extreme cold event referenced above. Increased cloud
cover would mitigate both daytime warming and especially
nighttime cooling, meaning Saturday night may not be as cold as
previously feared. Indeed, the official forecast for this period
has eased with Sunday morning lows now forecast "only" from
around -10 northeast to 0 southeast, however, there is
considerable spread in the possibilities. If trends with the
southern winter storm turn back southward and our skies are
clearer, then Sunday morning will likely fall to temperatures
near Saturday morning levels. However, if skies are mostly
cloudy then they may trend even "warmer" than currently
advertised. Given these uncertainties, have maintained the
Extreme Cold Watch area-wide from noon Friday onward. Subsequent
updates will determine whether that is eventually converted to
a warning, an advisory, or a mixture.

The long-range forecast for next week still appears relatively
active, unfortunately, with Iowa lying on the southern fringes
of broadly cyclonic west northwesterly flow aloft, and multiple
waves traveling through that flow during the week. The first of
these will move through around Sunday night, sweeping out any
remaining clouds/light snow from the weekend system and bringing
another shot of cooler air with Monday morning lows again below
zero statewide. A brief respite will then allow for some
temperature moderation around Monday and Tuesday, before more
waves move through in the latter half of next week.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 524 AM CST Thu Jan 22 2026

Patches of low stratus clouds are moving near the Minnesota/Iowa
border this morning and may produce brief flurries and MVFR
ceilings around FL020-030 at MCW and ALO in the next several
hours. Thereafter, as winds increase this afternoon and evening
BLSN may reduce visibility at MCW/ALO but the magnitude of
visibility reduction will not be as severe as yesterday. Low
confidence in magnitude, so have advertised intermittent 3SM
BLSN in the TAFs at those sites, but amendments are likely. At
the southern terminals, VFR conditions are forecast through the
TAF period.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...

Extreme Cold Warning from 9 PM this evening to noon CST Friday
for IAZ004>007-015>017-023>028-033>039-047>050.

Extreme Cold Warning from midnight tonight to noon CST Friday
for IAZ044>046-057>062-070>075-081>086-092>097.

Extreme Cold Watch from Friday afternoon through Saturday
morning for IAZ004>007-015>017-023>028-033>039-044>050-057>062-
070>075-081>086-092>097.

&&

$$

DISCUSSION...Lee
AVIATION...Lee