Sioux City, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

389
FXUS63 KFSD 240858
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
258 AM CST Sat Jan 24 2026

.KEY MESSAGES...

- Despite light winds, wind chills -20 to -30F will be common
  over the area through mid-morning, coldest north of I-90.

- Another night of dangerous cold is likely Sunday night, with
  a moderate to high (40-90%) chance of wind chills of -25 or
  colder mainly northeast of a Huron to Sioux Falls to Storm
  Lake line.

- Less cold temperatures for Monday onward, though still below
  normal for the last week of January. Light snow chances late
  tonight-Sunday, and again Tuesday night-Wednesday. Low (<20%)
  probability of snowfall reaching 1 inch in either period.

&&

.DISCUSSION...
Issued at 258 AM CST Sat Jan 24 2026

TODAY-SUNDAY NIGHT: Arctic high pressure moving through the
Upper Mississippi Valley and into the western Great Lakes today,
allowing a modest southerly flow to develop through the morning.
Winds may begin to increase just enough ahead of the rise in
temperatures to see advisory level wind chills (-25F or colder)
persist through 9-10 AM. Cannot rule out a brief dip to colder
wind chills toward south central South Dakota as the winds begin
to pick up prior to daybreak, or lingering an hour beyond the
current expiration, but overall the advisory remains on track.

Weak warm advection will help temperatures recover above zero in
most areas by this afternoon, with readings dropping back into
the single digits below zero tonight. A compact surface low
looks to develop in southwest-south central South Dakota tonight
in response to a mid-upper level wave dropping southeast across
the Dakotas. NBM maintains a dry forecast with this feature, but
deterministic models in fairly good agreement in producing some
light QPF across our South Dakota counties late tonight through
midday Sunday. Coordinated with neighboring offices to introduce
some low-moderate (20-40%) pops and light snow accumulation to
areas mainly west of I-29. While ensemble probabilities support
these chances for measurable snow, probabilities are generally
very low (<10%) that amounts will reach 1 inch. May have to
watch northwest portions of the forecast area, however, as the
HREF does indicate a small pocket of higher probabilities for
near/west of the James River Valley (Huron/Mitchell).

Another shot of colder air builds in behind this wave for Sunday
night, bringing our next period of advisory level wind chills
for later Sunday night into Monday morning. Probabilities remain
moderate to high (40-90%) that areas northeast of a line from
Huron-Sioux Falls-Storm Lake will see wind chills below -25F
Monday morning, with a low (~20%) probability of wind chills
reaching -35F in portions of southwest Minnesota.

MONDAY-WEDNESDAY: After bottoming out in the single digits and
teens below zero Monday morning, temperatures quickly recover
through the day Monday. This could be the warmest day of the
week ahead with highs from the teens in southwest Minnesota to
near/just above freezing in south central South Dakota. A dry
cool front moves through Monday night, followed by another weak
wave later Tuesday night into Wednesday. This latter wave will
have a bit more moisture to work with, but model differences in
the track of the wave are keeping pops on the low side for now.
The broader ensembles showing 30-50% chance of measurable snow
occurring on Wednesday, with low (~20%) probability of amounts
nearing an inch in portions of southwest Minnesota.

THURSDAY-FRIDAY: Low confidence in temperatures as we head into
the final days of January 2026, with NBM temperature spreads
climbing to as much as 30-40 degrees between the 10th and 90th
percentiles by Thursday and Friday. Somewhat higher confidence
that this period remains dry with <20% probabilities of seeing
measurable precipitation.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1026 PM CST Fri Jan 23 2026

VFR conditions are expected to prevail for the majority of the
period. Winds are light and variable becoming southerly and light
after the passage of a surface high pressure.

A shallow layer of moisture and weak lift provided by omega has
resulted in a mid-layer cloud deck. This deck is expected to slowly
sink as air aloft subsides. While ceilings will decrease to around
6000-9000 ft AGL, they should remain VFR. Toward the end of the
period, soundings indicate some scattered MVFR clouds are possible
across much of the region in the late afternoon.

Very low chances (<15%) for light snow/flurries along the Missouri
River counties, including KSUX from now until 24.12Z. Very little if
any accumulation is expected and impacts to flight operations are
not anticipated.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Cold Weather Advisory until 9 AM CST this morning for
     SDZ038>040-054>056.
MN...Cold Weather Advisory until 9 AM CST this morning for MNZ071-
     072-080-081-089-090-097.
IA...None.
NE...None.

&&

$$

DISCUSSION...JH
AVIATION...AJP