610
FXUS63 KFSD 221741 AAC
AFDFSD

Area Forecast Discussion...UPDATED
National Weather Service Sioux Falls SD
Issued by National Weather Service Aberdeen SD
1141 AM CST Sat Nov 22 2025

.KEY MESSAGES...

- Warm conditions will continue through the weekend, with highs
  mainly in the 50s. Some spots could reach the low-60s today
  and Sunday, especially along the Missouri River Valley.

- There is a 60 to 80 percent chance of rain Monday into Monday
  night. Lingering rain will transition to light snow over east
  central SD and western MN during the day Tuesday as much
  colder air moves in Tuesday and remains through the rest of
  the week.

- Winds gusting 35 to near 45 mph will be possible over portions
  of mainly south central South Dakota Tuesday.

- Colder temperatures are set to move in next week, with single
  digit wind chills possible by Wednesday morning especially
  north of I-90. Thanksgiving is looking chilly as well, with
  more single digit wind chills possible Thanksgiving morning.

&&

.UPDATE...
Issued at 1129 AM CST Sat Nov 22 2025

Updated discussion for the 18Z TAFs below.

&&

.DISCUSSION...
Issued at 414 AM CST Sat Nov 22 2025

We`re starting out this morning with an area of low pressure set
up mainly over southern Manitoba, with a cold front stretching
southwest through ND and far western SD. Winds behind the front
have increased out of the west with gusts of 20-30mph. The dry
cold front will be mainly associated with some clouds and the
change in wind direction/speed. The cold front will sink along the
SD/NE border trough central MN by 18Z and with high pressure
quickly building in it. Despite the cold front, temperatures will
still rise into the 50s today, which is 10 to near 15 degrees
above normal for this time of year. Slightly warmer air will move
in Sunday, still topping out in the 50s, as a warm front shifts
north across the area.

Sunday night through Monday, the split upper-level flow over SD
pushes an upper-level low from the southwest US towards the
northeast. At the surface, low pressure over NM/CO starts to move
towards the northeast, though models vary the track and speed
slightly. The models have the low in MN by Monday night, with most
having the low move out of MN by Tuesday afternoon, however, the GFS
keeps the low over eastern MN until Wednesday morning. Precipitation
around this low is forecast to move into southern SD Monday morning
spreading north through the day with 30-60% chance for precipitation
over central and eastern SD by Monday night and 20-40% chance for
precipitation for areas north of I-90 Tuesday. Precipitation should
move out of SD/southwestern MN/northwestern IA western Tuesday
night, however if the low follows what the GFS is showing,
precipitation chances could stay around for a bit longer.

With warmer temperatures around Monday, the precipitation will stay
as rain through the day and into the night. Late Monday night into
early Tuesday morning, the cooler temperatures will start moving in
causing the rain to start changing over to a rain/snow mix then snow
starting in central SD and moving into eastern SD by Tuesday
morning. By Tuesday afternoon, the precipitation should be mostly
snow for central and eastern SD. Snowfall amounts from this system
are currently forecast to stay below an inch for most of central and
eastern SD. There does look to be a 30-50% chance for greater than
an inch of snow to fall over the Prairie Coteau and 30-40% chance
for the Leola hills by Wednesday morning. There is a bit of spread
between the ensemble models over the Prairie Coteau for snowfall
amounts, varying between 0.5-4 inches, highest over the Sisseton
hills. There is more uncertainty over far southeastern SD and
northwestern IA, as precipitation may be mainly over before the
cold air moves in, which would result in little to no snow.

For mainly south central SD: Another hazard to note with this
system is the strong winds coming in as the cold air starts to
advect into SD Monday night through Tuesday. There is a bit of
variability in the winds as to the strength and how long they
last, specifically the GFS keeping its low pressure in MN longer
causing winds to be much stronger and staying around for
longer. Ensembles are showing a 30-50% chance for wind to gust
greater than 45mph occurring over central SD during the day
Tuesday while the GFS is showing gusts up around 50-55mph. The
differences between the model solutions, as well as the
ensembles decreasing the wind speeds slightly over the past few
runs, causes some uncertainty in the strength of the winds
Monday night through Tuesday. This will need to be monitored as
the system gets close to see if the solutions come to an
agreement. These strong winds in combination with the snow
falling Tuesday have the potential to cause blowing snow in
areas, especially over the Leola hills and along the Prairie
Coteau. This blowing snow could reduce visibilities at times
causing hazards to those who are traveling.

The colder air moving in with this system will cause temperature
that are 10-15 degrees warmer than normal on Monday to drop like a
rock. Higher surface pressure moving into central and eastern
SD/northeastern NE and edging into southwestern MN/northwestern
IA with winds from the northwest Wednesday and Thursday will
help to keep precipitation out of the area while also lowering
temperatures to be 5-10 degrees colder than normal by Thursday,
with highs in the 20s to low 30s and low temperatures in the
teens.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1129 AM CST Sat Nov 22 2025

VFR conditions will prevail at all TAF sites through Sunday
afternoon with scattered to few high clouds passing over the
region. Northwest winds will gradually shift out of the
south/southwest by early Sunday morning, continuing through
Sunday afternoon. Other than gusts between 15-25kts this
afternoon, winds will overall be light this evening through
Sunday.

&&

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

&&

$$

UPDATE...MMM
DISCUSSION...06
AVIATION...MMM