482
FXUS63 KFSD 281755 AAA
AFDFSD

Area Forecast Discussion...UPDATED
National Weather Service Sioux Falls SD
1155 AM CST Fri Nov 28 2025

.KEY MESSAGES...

- Snow spreads east through the region this afternoon,
  persisting through Saturday afternoon. Snow amounts have
  increased, with most of the area expected to see more than 4
  inches of snow and over 6 inches for areas along and east of
  I-29. A glaze of ice is expected south of I-90 into the
  southern Missouri River Valley and US Highway 20 corridor.

- Expect disruptions to travel today through the weekend; travel
  will become increasingly difficult if not impossible in some
  areas, especially Saturday afternoon. Be sure to check road
  conditions before traveling, and be prepared to adjust your
  plans. If you must travel, keep a preparedness kit in your
  car.

- Much colder air spreads in by Sunday and continues most of
  next week with the lows down to the single digits and wind
  chills below 0F.

&&

.DISCUSSION...
Issued at 540 AM CST Fri Nov 28 2025

THROUGH SATURDAY NIGHT: Main focus of this forecast is on the
upcoming winter system, with numerous winter weather headlines in
effect across the region and potentially major disruptions to travel
expected through the post-Thanksgiving weekend. Discussion broken
into synopsis, accumulation/rates, winds, and headlines.

SYNOPSIS: Lee-side low pressure in the eastern Rockies develops
through this morning with the first pass of WAA and jet streak
moving into the region by daybreak. Frontogenesis increases with the
WAA, which will lead to a band of snowfall moving east through the
day and into the evening hours with the mid level wave. Expect a
struggle with saturation initially, so snow may take a bit to reach
the ground. Additionally, we should see brief periods of freezing
drizzle or a mix of FZDZ/SN this evening and tonight south of I-90
along the southern MO River Valley and the US Hwy 20 corridor as we
lose the saturation to the DGZ leading to a glaze of ice.

Tonight, we begin to see the surface low eject out of CO into NE,
with continued WAA and the next mid/upper level trough. We may see a
lull in snow with some drier air moving in, but will see the next
round of precip move in from the west fairly quickly so stayed
pretty heavy handed with POPs while trying to show the lull a bit.
Expect snow to continue through the day Saturday, with moderate snow
at times. May see additional banding, although guidance is varied on
the placement of the strongest f-gen. Low pressure and upper trough
move east of the area through Saturday night, with much colder air
in its place.

ACCUMULATIONS/RATES: Snow totals have increased a couple of inches
most places with the increase in QPF for this event. Most of the
area is now looking at 4" or more of snow, with areas east of I-29
looking at 6" or more. Locations in northwestern IA east of IA State
Hwy 60 may see more than a foot of snow (20-50%+). Areas in the
James River Valley may see some amounts toward 6" or more, but there
is a little more uncertainty in that area with guidance more split
here. Generally through the event, snowfall rates of 0.25" to 0.75"
per hour. However, enhancement in the f-gen/other forcing this
evening/tonight may lead to 1" per hour rates across portions of
northwestern IA. Could see some brief heavier rates Saturday as well.

WINDS: Winds start off easterly today and into tonight, with the
strongest winds across south central SD gusting to 30 mph through
the day and into the evening. With falling snow, expect reduced
visibility and some blowing/drifting. Winds shift to northwesterly
Saturday, and will be breezier across the area. Again, main impacts
with widespread wind gusts 25-35 mph will be the blowing and
drifting potential. Be prepared for reduced visibility and difficult
to possibly near impossible travel conditions.

HEADLINES: With the increase in snow amounts, have tweaked the
headlines slightly. Added Gregory county to a Winter Weather
Advisory. The Winter Storm Warning has been expanded west and north,
to now include most of the I-29 corridor. Further expansion to the
Winter Storm Warning is possible, if trends west of I-29 into the
James River Valley continue to increase.


SUNDAY ONWARD: Given the focus on the short term, no changes to the
extended along with a limited discussion. Sunday looks to be dry and
colder as high pressure moves into the region. Highs Sunday will
struggle to get out of the teens, with lows in the single digits
either side of zero. Colder temperatures, 10 or so degrees below
average, continue through next week, although some locations should
moderate back closer to normal. A couple of quick moving
waves/troughs moving through could lead to some light precipitation
chances early and mid week, although confidence is low given model
disagreements and overall lack of moisture. Periodic breezy
conditions, which could lead to some blowing/drifting issues on
Monday. Wind chills fall below zero at times.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1141 AM CST Fri Nov 28 2025

A winter storm will bring snow accumulations and gusty winds to
the region through Saturday afternoon. MVFR stratus and light to
moderate snow will expand eastward through the I-29 corridor
this afternoon. Moderate to heavy snow and LIFR visibility are
possible at times. This evening, may see FZDZ south of I-90,
near YKN-SUX, leading to a light glaze of ice. There will be
some improvements in vsby tonight into early Saturday morning
as snow coverage lessens at times, but confidence is low in
exact timing of vsby/cig changes IFR and below. The heaviest
snowfall accumulations will occur near and east of IA/MN Highway
60, impacting KSUX and KSPW.

Expect light southeast winds today with occasional gusts up to
25 kts heading into the evening. Winds veer northeasterly
overnight, increasing and becoming northerly by mid day
Saturday. Blowing and drifting snow will lead to reduced
visibility at times, especially Saturday.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Winter Storm Warning until midnight CST Saturday night for
     SDZ055-056-062-066-067-069>071.
     Winter Weather Advisory until noon CST Saturday for SDZ038-039-
     050-052>054-057>061-063>065-068.
     Winter Weather Advisory until midnight CST Saturday night for
     SDZ040.
MN...Winter Storm Warning until midnight CST Saturday night for
     MNZ071-072-080-081-089-090-097-098.
IA...Winter Storm Warning until midnight CST Saturday night for
     IAZ001>003-012>014-020>022-031-032.
NE...Winter Storm Warning until midnight CST Saturday night for
     NEZ013-014.

&&

$$

DISCUSSION...SG
AVIATION...BP