Flandreau, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

748
FXUS63 KFSD 060454
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
1054 PM CST Fri Dec 5 2025

.KEY MESSAGES...

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

- Snowfall rates could be as high as 1-1.5" an hour in the
  heaviest snow especially Saturday afternoon and early evening,
  which would cause visibility reductions and quickly
  accumulating snowfall. Be sure to use extra caution on the
  roads and prepare for potential travel delays.

- Cold wind chills move in once again Saturday night, with wind
  chills down to the -5 to -15 degree range by Sunday morning.

- Near to below normal temperatures will continue into the new
  week with the next chances for precipitation possible on
  Tuesday.

&&

.DISCUSSION...
Issued at 302 PM CST Fri Dec 5 2025

It was a much warmer day out there today compared to yesterday,
with highs into the 30s area-wide. Spotty snow and rain showers
continue to push across the area, but we should dry out heading
into tonight. Temperatures will drop tonight behind a weak
frontal boundary into the lower 10s to lower 20s, so a chilly
night is ahead. This will set the stage for our next snowmaker
set to impact the area during the day Saturday into Saturday
evening. A band of snow looks to develop off to our west around
daybreak Saturday and push eastward into our area. Snow should
begin around sunrise west of the James River, by the late
morning/early afternoon time frame for the I-29 corridor, and
then spread into the rest of northwest Iowa and southwest
Minnesota through the afternoon. Due to the later start time
expected for the I-29 corridor, did move the start time up for
the Winter Weather Advisory there to begin at 9 am Saturday.
Snow should wrap up from west to east through the evening hours.
This is slightly slower than what guidance was showing
overnight, so opted to extend the Winter Weather Advisory for
northwest Iowa and southwest Minnesota until midnight Saturday
night/Sunday morning.

Unlike our last winter storm, which was more of a slowly
developing system, this one will be quick moving with higher
snowfall rates, potentially up to an inch to inch and a half per
hour at times especially in the afternoon and early evening
hours. This means snow will accumulate quickly after it begins
and visibility will be reduced. Speaking of accumulations, we
look to generally see around 3-6" along and east of the James
River. West of there, amounts looks to be in the 1-3" range. The
highest snowfall totals will be in and around the Iowa Great
Lakes to the Jackson, MN area, where locally 6-7 inches of snow
will be possible. Opted to not upgrade to a Winter Storm Warning
for these areas for two reasons. One, amounts of at least 6
inches or more are expected to remain isolated at this time, and
without excessive wind to blow things around, we won`t be
anywhere near whiteout concerns or anything like that. Second,
guidance has been a bit inconsistent on where the heaviest
snowfall rates will end up, with some guidance indicating this
heavier band setting up either along the I-90 corridor in
southwest Minnesota, or over portions of northwest Iowa, or
even into central Iowa (out of our county warning area). Future
upgrades may be necessary if guidance either starts to signal
more widespread 6+ inch totals or if guidance comes into better
agreement, so keep up to date with the latest forecast! Either
way, extra caution should be used on the roadways on Saturday.

From there, we get colder, with temperatures Saturday night dropping
to the single digits on either side of zero. Wind chills look to be
in the negative 5 to negative 15 degree range by Sunday morning.
Highs on Sunday only look to be mostly in the single digits to low-
10s, perhaps slightly warmer where less snowpack is expected (south-
central SD). Temperatures look to moderate heading into the next
work week, with temperatures rising above freezing across the entire
area by Tuesday. Another storm system will move in Tuesday into
Tuesday night. With the warmer temperatures in place, there`s a
chance this system starts out as all rain, with perhaps a changeover
to snow on the backside of the system. Details remain uncertain as
it will come down to the track of the system, which this many days
out is highly uncertain. Either way, temperatures look to cool off
below normal again after this system moves through.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1054 PM CST Fri Dec 5 2025

MVFR stratus continues to blanket the majority of the area late this
evening. Some breaks in the stratus are present west of I-29. The
stratus behind these breaks is variable in ceiling impact as
ceilings range between VFR/MVFR. These variable ceilings will
persist through the night before the next chance for snow moves into
the area tomorrow morning. Ceilings and visibilities will lower to
MVFR/IFR/LIFR levels across the area as snow begins to fall. Snow
will persist through the afternoon hours before beginning to clear
during the evening hours. Winds will turn to out of the southeast
tonight and become a bit breezy by tomorrow afternoon with gusts up
to 15 to 25 knots. The breezy winds may lead to patchy blowing snow
while snow is falling. Ceilings and visibilities look to lift a
little bit in the aftermath of the snow but remain around MVFR
levels. These conditions look to finish out the TAF period.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory from 9 AM to 9 PM CST Saturday for
     SDZ040-055-056-061-062-066-067-069>071.
     Winter Weather Advisory from 6 AM to 6 PM CST Saturday for
     SDZ038-039-052>054-058>060-064-065-068.
MN...Winter Weather Advisory from noon Saturday to midnight CST
     Saturday night for MNZ071-072-080-081-089-090-097-098.
IA...Winter Weather Advisory from noon Saturday to midnight CST
     Saturday night for IAZ001>003-012>014-020>022-031-032.
NE...Winter Weather Advisory from 9 AM to 9 PM CST Saturday for
     NEZ013-014.

&&

$$

DISCUSSION...Samet
AVIATION...Meyers