418
FXUS63 KABR 210530 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1130 PM CST Tue Jan 20 2026

.KEY MESSAGES...

- Another round of light accumulating snow moves in on Wednesday
  with generally less than an inch expected.

- Gusty northwest winds develop on Wednesday ranging from 35-50
  mph with the strongest winds expected across central South
  Dakota. Blowing snow and reduced visibilities are expected,
  especially in falling snow. A Winter Weather Advisory has been
  issued.

- Very cold temperatures and dangerous wind chills expected
  Thursday through Sunday morning. The coldest period will be
  Friday with wind chills Friday morning ranging in the thirties
  to forties below zero. Actual high temperatures for Friday are
  forecast to range from zero to the teens below zero. An Extreme
  Cold Watch is in effect for Thursday evening through Friday
  afternoon.

&&

.UPDATE...
Issued at 1116 PM CST Tue Jan 20 2026

See below for an aviation forecast discussion for the 06Z TAFs.

UPDATE Issued at 810 PM CST Tue Jan 20 2026

Today`s shortwave/snow event is moving off toward Nebraska/Iowa,
and the remaining few pockets of flurries over the CWA are
continuing to shrink/taper off. The next shortwave set to impact
the CWA is noted up in Saskatchewan, headed this way. No changes
planned to the tonight period forecast.

UPDATE Issued at 527 PM CST Tue Jan 20 2026

See below for an aviation forecast discussion for the 00Z TAFs.

&&

.DISCUSSION...
Issued at 136 PM CST Tue Jan 20 2026

Light snow continues to slide southeast through the region this
afternoon with the shortwave trough. The next round moves in
Wednesday morning, generally following the same track. The big
difference will be the winds. Northwest winds will mix down from the
100kt jet with around 55kt at 700 mb and 40 to 50 kts at 850mb. CAA
is lacking but there is drier air coming in from the west Wed
afternoon with a building sfc high. This air mass should steepen
lapse rates, though behind any snowfall. Regardless, winds gusting
to 45 mph with fresh snow from today and new snow (up to an inch) on
Wednesday will cause blowing snow and reduced visibilities. Issued a
Winter Weather Advisory for areas north of I-90 and a wind advisory
along I-90. The reduced vsby will likely be in pockets and worse in
open areas.

The deep upper trough rotates in on Thursday, digging into the
northern Plains and Great Lakes. There is significant thermal
packing with H85 temps falling into the -30s Celsius as a 1050s mb
high builds in from the northwest. Issued a Cold Weather Watch for
Thursday night into Friday morning when wind chills may fall to -35
to -45 degrees. Friday night looks marginally warmer, potentially
only meriting a cold advisory. Temperatures will rebound further by
Monday when upper ridging begins to transition in from the west. Not
in the official forecast as yet, but also can`t rule out another
light snow event Saturday in between sfc highs.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1116 PM CST Tue Jan 20 2026

Terminals KABR,KATY,KPIR,KMBG

Skies and surface visby, at the moment, are mostly VFR and should
prevail through the rest of tonight. Toward sunrise, the next
period of light snow should begin working down across the CWA,
mainly across north central and northeast South Dakota into west
central Minnesota. Within a few hours of falling snow beginning,
rather strong northwest winds 20 to 35 knots with gusts of 45 to
50 knots should develop. Snowfall, combined with these strong
winds, should create sub-VFR visibility in falling/blowing snow
during the day on Wednesday. Just prior to the boundary layer
connecting to a deeper mixing layer aloft Wednesday morning,
there will be some low level wind shear potential over the region
for a few hours.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory from 8 AM to 6 PM CST Wednesday for
     SDZ006>008-011-018>023.

     Extreme Cold Watch from Thursday evening through Friday
     afternoon for SDZ004>011-016>023-036-037.

     Winter Weather Advisory from 6 AM CST /5 AM MST/ to 3 PM CST /2
     PM MST/ Wednesday for SDZ003>005-009-010-015>017-033>037-
     051.

     Wind Advisory from 9 AM to 4 PM CST Wednesday for SDZ045-048.

MN...Winter Weather Advisory from 8 AM to 6 PM CST Wednesday for
     MNZ039-046.

     Extreme Cold Watch from Thursday evening through Friday
     afternoon for MNZ039-046.

&&

$$

UPDATE...10
DISCUSSION...20
AVIATION...10