754
FXUS63 KABR 011703 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1103 AM CST Mon Dec 1 2025

.KEY MESSAGES...

- Breezy southerly winds will lead to subzero wind chills through
  midday. An area of enhanced southwest winds across the Sisseton
  Hills today could lead to some patchy blowing snow.

- A quick moving disturbance will push through the region the latter
  half of Tuesday into early Wednesday and kick off some light
  precipitation in the form of snow and a wintry mix.

- Very cold air across the region Wednesday night, with lows in
  the single digits below and teens below zero. Wind chills may
  reach 25 below to 30 below zero in the James River valley.

- Show chances (20-30%) return Friday night/Saturday as another
  clipper system potentially moves through.

&&

.UPDATE...
Issued at 1100 AM CST Mon Dec 1 2025

See below for an aviation forecast discussion for the 18Z TAFs.

UPDATE Issued at 901 AM CST Mon Dec 1 2025

No appreciable updates planned to the today period forecast.

UPDATE Issued at 539 AM CST Mon Dec 1 2025

The aviation discussion has been updated for the 12Z TAFS.

&&

.SHORT TERM /TODAY THROUGH TUESDAY AFTERNOON/...
Issued at 443 AM CST Mon Dec 1 2025

A mixture of clear skies and low stratus early this morning across
the forecast area. Southerly low level flow has led to low stratus
streaming northward and downwind of Lake Oahe and nearby sections of
central SD. There could perhaps be a few flurries associated with
this but haven`t seen any evidence yet from sfc obs and SDDOT
webcams. Seems as if winds remain stirred enough to prevent any fog
development, but something to watch the next few hours. Other low
stratus is shifting northeast across northeast SD and west central
MN.

Sfc high pressure ridge will continue drifting farther away from our
forecast area early this morning which will promote an increase in
southerly breezes through midday. As a result, subzero wind chills
will still remain present. Hi-res guidance does point to gusty
southwest winds developing across the Sisseton Hills and downslope
area by mid morning through late afternoon or early evening. Did
increase winds speeds and gusts in that area but not enough to kick
off much for blowing snow. It`ll be something the incoming day shift
will have to keep an eye on for further adjustments to the forecast
if needed. An upper trough axis will swing southeastward across the
region today. A few flurries may be possible as far north as the I-
90 corridor in our far southern zones in south central SD through
the early morning hours and perhaps beyond daybreak but mostly dry
conditions will be the rule across most of the CWA today.
Temperatures will remain rather chilly, especially across areas that
have a deeper snowpack. Teens for highs will be prevalent from
portions of central and north central SD into northeast SD and west
central MN. Some low level WAA will aid in afternoon readings
reaching the low to mid 20s south and west of the Pierre area.

A warm front approaches the region tonight into Tuesday morning.
Clear to partly cloudy skies early on through the evening will allow
temperature readings to fall quickly into the single digits above
and below zero. HREF probs for temperatures colder than 0F range
from 40-80 percent across north central and northeast SD into west
central MN. Clouds increase from west to east tonight into early
Tuesday. Depending on how quickly they increase will play a factor
in how quickly temperatures fall tonight. We might see readings
stabilize or increase a bit closer to daybreak Tuesday. That warm
front is all part of the next disturbance that will shift east into
the Dakotas during the day. There will be enough moisture for this
clipper like system to work with to produce a round of light snow
and perhaps a rain/snow/sleet mixture closer to midday and afternoon
hours. At this point, QPF values remain light, so not anticipating
anything too heavy, but a light coating of snow will be possible for
some areas by late in the afternoon. How quickly that warm front
moves through our area will dictate how warm temperatures get.
Central SD has a shot at readings in the low to mid 30s. Some
question remains though farther east and in areas that have the
deepest snowpack. Nonetheless, at least highs in the 20s look
probable.

&&

.LONG TERM /TUESDAY EVENING THROUGH SUNDAY/...
Issued at 443 AM CST Mon Dec 1 2025

Tuesday night will still be dealing with the passing low pressure
and associated warm front/cold front passages and resultant
snow/mixed precip chances. Continued the trend from the short term
with increasing PoPs across the region. Grand Ensemble shows a large
area of 40-70% chances for measurable precipitation in a 6-hr period
ending at 06Z Wednesday. Highest chances show up on the Coteau
region. Did raise PoPs slightly more into the 30-50% range across
much of the CWA for Tuesday evening before chances decrease quite a
bit beyond 06Z Wednesday. Cannot rule out light snow accumulations
continuing into Tuesday evening, but Grand Ensemble showing only
<20% chance of seeing anything more than a half inch. Thermal
profiles/surface temperatures would support mixed precip across
central SD, although rather light QPF generally less than a tenth
(90th percentile) likely.

Cold front will also be moving through the region Tuesday night,
with a surface high building into the day Wednesday. Much colder air
with 925mb temps likely from -15C to -17C across the area during the
day Wednesday. Current forecast highs are only in the teens. But
it`s Wednesday night when the heart of the cold air settles in as
lows drop into the single digits below and teens below zero.
Interesting to note current apparent T forecast is in the 25 below
to 30 below range in the James River valley 06Z to 12Z Thursday.

GEFS/ENS/GEPS 6-hr mean MSLP and mean 6-hr precip shows another
clipper system potentially sliding southeast across the High
Plains/Northern Plains Friday night into Saturday, with inherited
chances generally in the 20-30% range.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1100 AM CST Mon Dec 1 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions look to persist for the most part during this TAF
cycle. Breezy conditions at times will be possible with strongest
gusts of 20-25 knots at KATY. This afternoon, once winds become
a bit more westerly at KMBG and KPIR, there could be some gusts up
to 20 knots.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

UPDATE...10
SHORT TERM...Vipond
LONG TERM...TMT
AVIATION...10