181
FXUS63 KABR 151731 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1131 AM CST Thu Jan 15 2026

.KEY MESSAGES...

- Snow this evening into Friday of 1 to 2 inches with locally
  higher amounts possible.

- Strong northwest wind gusts of 40 to 55 mph are expected by
  early this afternoon across central and north central South
  Dakota, with an increase to 50 to 65 mph later tonight into
  Friday. A Wind Advisory has been posted for this afternoon into
  this evening, while a High Wind Watch continues late tonight
  through Friday for areas west of Brown and Spink counties.

- These winds, when combined with areas of falling snow, could
  lead to brief periods of significantly reduced visibility and
  hazardous travel conditions, especially if snow squalls occur.

- Strong winds return Sunday, when gusts behind a cold front may
  reach up to 45 mph west of the James River Valley.

&&

.UPDATE...
Issued at 1130 AM CST Thu Jan 15 2026

Updated for the 18z Aviation discussion below.

UPDATE Issued at 1124 AM CST Thu Jan 15 2026

The High Wind Watch for later this evening/overnight through
Friday has been upgraded to a High Wind Warning. Much of the rest
of the forecast remains unchanged at this time with the main
concern being increasing winds today that will remain elevated
through the day Friday. Winds have been increased slightly for
Wednesday afternoon into Wednesday evening.

&&

.SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/...
Issued at 417 AM CST Thu Jan 15 2026

At 3 AM CST, skies are partly cloudy and temperatures are in the
teens to around 30 degrees. South winds 5 to 15 mph with some higher
gusts are happening as well.

A look at the latest surface analysis reveals that the parent
surface low is well up in central Canada, heading for the Hudson Bay
region. This system`s warm front extends down across the CONUS
northern plains and is just about to enter the northwest corner of
the CWA. Low level WAA should be at a premium across the CWA over
the next 9 hours or so. Tough in this kind of flow pattern sometimes
to analyze surface cold fronts. Not seeing any cold fronts right now
within several hundred miles of this CWA. It`s later this afternoon
after 18Z that warm northwest boundary layer winds begin to become
cool northwest boundary layer winds (weak low level CAA starts up).
As this low level CAA component is added to the mixing layer, lapse
rates within the lowest 3km of the atmosphere begin to sink up, and
some wind advisory potential gusts could be achieved. Momentum
transfer tool output in BUFKIT suggests sub-High Wind Warning
criteria winds will begin to overspread the CWA from northwest to
southeast (stopping short of the James River valley) mainly in the
early afternoon through late evening timeframe before any potential
for strong winds/gusts to develop may happen. There is less than
ideal pressure rises with this unfolding event and the low level CAA
probably isn`t sufficient either until after 06Z tonight. So, have
issued a wind advisory for the western half of the CWA from appx mid-
day/early afternoon through midnight tonight and then pick
up/continue with the High Wind Watch for late tonight through
Friday. It`s not a slam dunk. Models keep delaying the onset of High
Wind warning conditions.

The other fly in the ointment is snowfall coverage and amounts from
appx 23Z this afternoon through late in the day Friday. The latest
iteration of model solutions has some of these "snow streamers"
showing up now moving down into the CWA out of North Dakota over in
north central South Dakota as early as early this evening, with some
streamers potentially capable of producing 0.5-1.5in of snowfall.
Combined with the strong winds expected to be in place across
central and north central South Dakota, the blowing snow model is
now generating blowing snow, including some localized areas (not
widespread) that would satisfy blowing snow winter weather advisory.
The somewhat more widespread coverage of blowing snow winter weather
advisory conditions appears to be lining up over the Prairie Coteau
where 1-2.5in of snow accumulation is forecast. The latest trends in
snow squall output is for there to be an initial surge of pre-arctic
fropa low level "cold air CAPE" and steep low level lapse rates
sweeping southeastward across the CWA between appx 22Z this
afternoon and 04Z this evening. Then, with the secondary/arctic cold
fropa sweeping south through the CWA between appx 06Z and 11Z
Friday, there is still some lower-bound CAPE values (~25-75J/kg) and
5-7C/km low level lapse rates leftover to tap into along the
boundary for perhaps a second round of stronger snow showers/squalls
to deal with. Again, outside of the Prairie Coteau region, guidance
is for snow accumulations to be mainly associated with these bands
or streamers of snow, which are not "widespread", but more
localized. Snowfall amounts could be characterized as a skiff to
around an inch or so "with locally higher amounts". It`s within
these localized areas that blowing snow could make for reduced
visibility, and pretty much just when it`s snowing. If the band of
snow moves away, or someone drives into and then back out of a band
of this stuff, visby should quickly fall and then quickly improve
again. Tough call for what type of headline or product to use. Over
on the Coteau, where wind speeds may be a bit more pedestrian (only
wind advisory strong), but areal coverage of 1 to 2+ inches of snow
could be more widespread in nature, that area seems more like a
candidate for a winter weather advisory for blowing snow (Clark,
Day, Marshall and Roberts counties), and probably from late tonight
through the end of the event.

&&

.LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/...
Issued at 417 AM CST Thu Jan 15 2026

Focus in the extended period now shifts to a system moving in
Sunday. This system will be driven by a low pressure center passing
to the east. A tightening pressure gradient will induce strong
northwest flow over the region, potentially bringing a return to a
wind headline. The strongest winds are still expected over central
and and north central South Dakota (all areas west of Brown and
Spink counties), showing a broad 40-60% probability of reaching Wind
Advisory criteria (30 mph sustained, gusts to 45). This low pressure
system will also drag a cold front across the forecast area, leading
to some potential development of some light snow showers. Model
soundings expect mainly shallow development, but temperatures may
be cold enough to support growth within the DGZ (therefore leading
to high SLRs) regardless. NBM probabilities for snow remain fairly
low, just showing around a 20% chance of any measurable accumulation
over the Prairie Coteau. Based on model soundings this feels perhaps
a bit too low, and forecaster expectation would be more in line with
the GEFS/Euro ensembles, giving broad 10-50% gradient from central
South Dakota and increasing moving northeast. Regardless, fairly
minor accumulations are expected at this time.

Beyond Sunday, temperatures take a brief dip Monday to below normal,
and Monday morning apparent temperatures could reach below -20
degrees. Mid-week, the upper-level ridge over the western CONUS
begins to deteriorate, which will help return the Aberdeen
forecast area to near-normal temperatures for this time of year.
Beyond Sunday`s light snow, the rest of the extended forecast will
have limited precipitation chances.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1130 AM CST Thu Jan 15 2026

Terminals KABR,KATY,KPIR,KMBG

Current VFR conditions are expected to continue through the day for
most of the area. Some post frontal stratus could develop during the
afternoon, though they should still stay in VFR ceilings. As a cold
front moves through later in the afternoon, northwest winds will
increase, with gusts getting up around 25-35kts. There could be some
light rain and snow showers that develop after the first cold front
moves though late this afternoon into the evening. A second cold
front will then moves through tonight. This will cause more snow
showers to move in along with stronger winds. These winds will
increase through the morning, with gusts of up to 35-45kts at
KABR/KATY and gusts up around 40-50kts at KMBG/KPIR. These stronger
winds in combination with the falling snow could lead to reduced
visibilities starting late Thursday night through Friday due to
blowing snow.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory until midnight CST /11 PM MST/ tonight for
     SDZ003>005-009-010-015>017.

     High Wind Warning from midnight CST /11 PM MST/ tonight to 6 PM
     CST /5 PM MST/ Friday for SDZ003>005-009-010-015>017-
     033>037-045-048-051.

     Wind Advisory until midnight CST /11 PM MST/ tonight for
     SDZ033>037-045-048-051.

MN...None.
&&

$$

UPDATE...12
SHORT TERM...10
LONG TERM...BC
AVIATION...12