Yankton, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

888
FXUS63 KFSD 061148
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
548 AM CST Sat Dec 6 2025

.KEY MESSAGES...

- A quick-moving winter system will bring mainly 3-6" of snow
  for most areas along and east of the James River today.
  Locally higher amounts over 6 inches will be possible around
  the Iowa Great Lakes into the Jackson and Worthington,
  Minnesota areas.

- Snowfall rates as high as 1-1.5" inches per hour within the
  heaviest band axis during the afternoon to evening hours will
  lead to rapid accumulations along and east of I-29. Visibility
  reductions and hazardous road conditions will lead to minor to
  moderate travel impacts at times affecting the evening commute.

- Cold wind chills will return each night through Monday with
  values as cold as 20 below possible.

- An active pattern aloft will lead to multiple precipitation
  chances through the work week. Continue to monitor the
  forecast moving forward.

&&

.DISCUSSION...
Issued at 255 AM CST Sat Dec 6 2025

TODAY & TONIGHT: A dreary and cooler day ahead! Taking a look across
the area, mainly overcast skies continue this morning with most
areas sitting in the mid to upper 20s. Don`t expect much change
during the day as overcast skies and slight breezy southeasterly
winds keep temperatures locked into the 20s to low 30s with the
warmest conditions along the Missouri River Valley. Taking a
look aloft, the forecast remains on track as a quick mid-level
wave dives across portions of South Dakota, Nebraska, and
Minnesota today bringing our next chances for snow. By daybreak,
should see light returns over central SD become more widespread
across southeastern SD as increasing dPVA and mid-level frontal
forcing interact with the WAA regime ahead of the surface
trough. From here, an enhanced area of snowfall should to begin
to take shape by late morning just south of the I-90 corridor in
southeastern SD and this should be the main driver of our
accumulations going forward. As this developing band of snowfall
gradually pivots southeastwards, HREF guidance continue to show
moderate to high confidence (60%-80%) in 1" in/hr or greater
snowfall rates which should lead to moderate to heavy
accumulations at times especially across far southeastern SD,
northwestern IA, and portions of southwestern MN.

With all of this in mind and collaboration with our neighbors,
decided to upgrade portions of our Winter Weather Advisory in
northwestern IA and southwestern MN into a Winter Storm Warning
where confidence was highest in 6+ inches of accumulations. While 3-
6 inches of accumulations continues to look like the most
likely range for most areas east of the James River, can`t rule
out additional upgrades in far southeastern SD and southwestern
MN if the axis of heaviest snowfall shifts northwards or
southwards. Otherwise, should see most of the snow taper off by
late evening. Shifting gears to impacts, falling snow and rapid
accumulations will lead reductions in visibility and hazardous
travel mainly in the afternoon to evening hours. As a result,
minor to moderate travel impacts are expected especially in the
areas with the highest accumulations so be prepared to post-pone
travel plans where necessary! Looking into the rest of the
night, a fresh snowpack and lighter surface winds will lead to
much colder conditions overnight with lows being on either side
of zero. Nonetheless, wind chill will likely be even colder with
values as low as 20 below possible mainly across southwestern
MN.

SUNDAY ONWARDS: Looking ahead, a surface high will move in to
replace the departing system on Sunday. Unfortunately, so will
another mid-level wave. With this in mind, additional light
accumulations will be possible from Sunday night into Monday mainly
along and north of I-90. The cold air plunge will continue as well
with highs mainly in the single digits to low 20s. From here, the
active pattern aloft will continue for the rest of the week. By
Tuesday, a decently strong clipper wave will dive across the
northern plains bringing our next chances for precipitation.
However, increasing warm air advection (WAA) and southerly surface
winds ahead of this system will likely keep most of the
precipitation as rain or a rain/snow mix given temperatures in the
upper 30s to upper 40s. As long-range guidance starts to diverge
between Wednesday to Thursday, it looks like another clipper will
fly through the northern plains. However, there are still subtle
differences in the timing and placement of features. Lastly,
temperatures will continue to trend colder from Wednesday onwards
with highs mainly in the teens to low 20s.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 540 AM CST Sat Dec 6 2025

A mix of VFR and MVFR conditions this morning will transition to
MVFR conditions and lower for the rest of the TAF period.
Looking at satellite imagery, MVFR stratus continues to blanket
the area this morning with upper level clouds moving overhead.
From here, areas of light snow across southcentral SD will
progress into our area throughout the day with light to moderate
accumulations expected. Falling snow could lead to periods of
IFR/LIFR vsbys along with IFR cigs from the lingering stratus.
Otherwise, southeasterly winds will back with the approaching
surface wave becoming more northerly to end the TAF period.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory from 9 AM this morning to 9 PM CST
     this evening for SDZ040-055-056-061-062-066-067-069>071.
     Winter Weather Advisory until 6 PM CST this evening for SDZ038-
     039-052>054-058>060-064-065-068.
MN...Winter Storm Warning from noon today to midnight CST tonight
     for MNZ089-090.
     Winter Weather Advisory from noon today to midnight CST
     tonight for MNZ071-072-080-081-097-098.
IA...Winter Storm Warning from noon today to midnight CST tonight
     for IAZ001>003-012>014-022.
     Winter Weather Advisory from noon today to midnight CST
     tonight for IAZ020-021-031-032.
NE...Winter Weather Advisory from 9 AM this morning to 9 PM CST
     this evening for NEZ013-014.

&&

$$

DISCUSSION...05
AVIATION...05