332
FXUS63 KFSD 042101
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
301 PM CST Thu Dec 4 2025

.KEY MESSAGES...

- Light snow is likely mainly north of I-90 late tonight into
  tomorrow morning, but accumulations are expected to be light.
  Light freezing rain (along with some sleet) looks to mix in
  when precipitation begins, with a light glaze possible along
  the Highway-14 corridor in central South Dakota mainly on
  elevated surfaces and untreated roads.

- Confidence is increasing in the potential for accumulating
  snowfall Saturday into Saturday night. There is a medium-to-
  high chance (40-70%) of at least 3 inches of snow, especially
  over portions of southeast South Dakota, northwest Iowa, and
  southwest Minnesota.

- Cold, below normal temperatures are expected to continue
  through the weekend, with signs of temperatures moderating
  closer to normal next week.

&&

.DISCUSSION...
Issued at 256 PM CST Thu Dec 4 2025

It was either a bitterly cold Thursday through and
through or a fairly decent December day depending on which side of
the stratus you ended up on. Where skies cleared early like in
central South Dakota, we`ve managed to make it to around 30 degrees
and even as mild as the low-40s! Where stratus lingered most of the
day like for areas east of the James River, we`ve only made it to
the teens for the most part. A milder night is ahead compared to
last night though, with temperatures dropping into the lower 10s
to middle 20s by sunrise Friday morning.

An active upper-level pattern will send a couple of waves through
the area this weekend. The first wave will bring a chance of mainly
light snow with some mixed precipitation, starting along the Highway-
14 corridor in central South Dakota and spreading eastward through
the morning, but mostly staying along and north of I-90 through the
day. Soundings indicate a warm nose around 900 mb during the onset
of precipitation, and with below freezing surface temperatures, we
will likely see some freezing rain mix in whenever precipitation
starts, along with some sleet as well. Not expecting much in the way
of ice accumulations, but can`t rule out a light glaze mainly on
elevated surfaces and untreated roads along the Highway-14 corridor
in South Dakota. As the warm layer diminishes with time, snow
will become the dominant precipitation type, though snow is
expected to remain light. We`ll see a dusting to a tenth or two
of an inch of snow, highest amounts over the Highway-14 corridor
in southwest Minnesota. Highs on Friday look to be in the 30s
across the area.

A stronger system will take shape on Saturday as another upper-level
wave moves in from the northern Rockies into the central Plains,
with a surface low developing over Wyoming in response. That surface
low looks to dive southeastward into central Nebraska, putting
us on the snowy side of the system. A band of snow looks to
develop in response to WAA at 850 mb, starting in central South
Dakota Saturday morning and spreading east-southeastward
throughout the day. Snow looks to exit off to our southeast into
central Iowa by the late evening. Snowfall rates could be
moderate to locally heavy at times, and this will likely lead
to a few inches of snow across much of the area, especially from
southeastern South Dakota into northwest Iowa and southwest
Minnesota. In those areas the NBM probabilities of at least 3
inches of snow ranges from 40-70%, while the probability of at
least 6 inches is around 10-30%. Winds don`t look to be too
strong with this system, but another messy travel day is growing
increasingly likely for Saturday, so keep up to date with the
latest forecast!

Colder air will move in after Saturday`s system, with lows dropping
to the single digits on either side of zero by Sunday morning.
Sunday will be cold with highs in the single digits to teens and
lows Sunday night once again in the single digits on either side of
zero. Our next best chance of precipitation looks to be around the
Tuesday-Wednesday time frame, though it is too far out to determine
specifics. At this point, temperatures look to be a little warmer
(or at least, closer to normal) by then, so the system may
bring us rain to start with a changeover to snow on the backside
of the system.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1138 AM CST Thu Dec 4 2025

An area of stratus will continue to slowly erode and move eastward
across the area through the afternoon, with the return of VFR
conditions expected at KFSD and KSUX by the late afternoon to early
evening. Tonight, some guidance shows the potential for fog
development, but left it out of the TAFs for now. Trends will be
monitored, but right now it looks like winds should stay elevated
enough to prevent widespread fog development. Our next system moves
in late tonight into tomorrow morning, brining the potential for
snow mixed in with some light freezing rain at times. Kept it as
snow in the TAFs for now as that is the most likely precipitation
type, but can`t rule out some light freezing rain (<25% chance at
the terminals). The best chance of snow will be north of I-90
especially into southwest Minnesota late tonight into tomorrow
morning. Heavy snow is not expected at this time, but any
snowfall could lead to MVFR visibilities.

Winds will gust to around 25-30 kts this afternoon (up to around 35
kts along the Buffalo Ridge) out of the south-southwest. Winds will
diminish overnight, though still could see a few gusts up to around
20 kts in southwest Minnesota and adjacent northwest Iowa late
tonight. Winds will turn more west-northwesterly heading into
tomorrow morning, picking up to around 8-12 kts by the end of the
period.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

$$

DISCUSSION...Samet
AVIATION...Samet