894
FXUS63 KFSD 102311
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
511 PM CST Wed Dec 10 2025

.KEY MESSAGES...

-  Winter weather advisory for mixed precipitation expanded for
   areas mainly near and north of I-90 and near and west of
   I-29. A band of snow will likely transition to a period of
   freezing rain through the morning into the early afternoon
   Thursday. Still some disagreement on location and amounts so
   further expansion and contraction of the advisory is
   possible.

-  A band of snow will be possible on Saturday. For now the
   better chances appear to be near and south of I-90. Overall
   looking like 1- 3 inch amounts.

-  Confidence continues to increase in arctic air bringing near
   advisory level wind chills to the region by this weekend.

-  Depending upon how much snow falls through Saturday, a
   milder pattern sets up for early next week.

&&

.DISCUSSION...
Issued at 208 PM CST Wed Dec 10 2025

A fairly strong wave will drop southeast through strong northwest
flow aloft late tonight into Thursday. Given thermal profiles across
the area concerns continue for a combination of freezing rain and
snow, especially near and west of I-29 and near and north of I-90.
Across southwest MN the majority of the precipitation would be snow
and for now those amounts would likely be 1-3". Also of concern with
this will be the precipitation increasing through the morning and
possibly beginning near the morning rush, although locations closer
to I-29 should see a start time closer to 8-10 am. Currently it
looks like precipitation will start as mainly snow, then transition
to freezing rain after a period. The impacts from any freezing rain
will be dependent upon how much snow falls first. For now snow
amounts before the freezing rain look to be fairly minimal so
believe that there will be some minor to moderate impacts from the
freezing rain, especially with the now bare roads and no snow or
slush to absorb some of this liquid precipitation as it is freezing.
So went ahead and expanded the advisory south to I-90 and east just
into MN and far northwest IA. Areas east of this advisory will see
more snow than freezing rain and amounts for now do not warrant an
advisory. Will also need to monitor potential for a light icing
south of I-90 Thursday morning into the afternoon but for now
confidence not high enough in this area for an advisory.

By late afternoon this lift will shift southeast and colder air will
filter southward. This should shut down precipitation from northwest
to southeast. Model soundings do indicate some saturation in the
lowest few thousand feet so will need to monitor for the potential of
a little light freezing drizzle as this system exits.

Otherwise a jet digs into northern MN and drags further cold air
into the region on Friday. This will bring a cold Friday to the
region with highs in the teens and wind chills dropping below zero
in many locations Friday afternoon.

The next chance for snow will come Friday night into Saturday. While
the wave is much weaker, thermally we are primed for snow
production. The DGZ basically runs from near the surface to about
600 mb. With somewhat weaker winds in the lower 2000 feet or so this
could prove to be a fairly efficient snow maker.

Cold air funnel in behind this system and Saturday night into Sunday
looks very cold. Could potentially see cold weather advisories
across the area during this time.

Sunday night into the middle of next week will see a pattern chance
with ridging building, then flat westerly flow expected, supporting
milder flow aloft and at the surface. Will have to keep an eye out
for a system Wednesday into Thursday.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 507 PM CST Wed Dec 10 2025

MVFR ceilings slowly crawl eastward this evening, taking a few
lingering flurries with it.

Clouds won`t clear however, as ceilings begin to lower from west
to east ahead of the next wave moving into the Plains. Very high
based snow may develop over central South Dakota by midnight,
with stronger surge of moisture and lift producing a winter mix
moving eastward during the day on Thursday. A layered mess of
snow, then freezing rain and sleet will develop through the
Tri-State area, with the mix of wintry types on the southwestern
side of the precipitation band. Ceilings and visibility may
occasionally fall to IFR or lower levels into mid-afternoon.

Current TAFS do not indicate sleet due to type simplicity, but
aviation interests should be aware of it`s increased risk from
mid-morning to mid-afternoon. Ice accumulations up to one tenth
will be possible, with mixed snow and sleet accumulations of a
dusting to an inch or two.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory from 8 AM to 6 PM CST Thursday for
     SDZ039-040-054>056-060>062-065>067.
     Winter Weather Advisory from 3 AM to 3 PM CST Thursday for
     SDZ038-052-053-057>059.
MN...Winter Weather Advisory from 8 AM to 6 PM CST Thursday for
     MNZ071-097-098.
IA...Winter Weather Advisory from 8 AM to 6 PM CST Thursday for
     IAZ001.
NE...None.

&&

$$

DISCUSSION...08
AVIATION...Dux