803
FXUS63 KABR 171336 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
836 AM CDT Tue Mar 17 2026

.KEY MESSAGES...

- A light wintry mix of snow, freezing rain, sleet, and/or rain
  over central SD this morning will switch to mostly snow over
  northeastern SD and west central MN through late this afternoon.


- Light snow accumulations of a light dusting over central SD up
  to an inch over northeastern SD is expected. Additionally, a
  light glaze of ice is possible over mainly central and south
  central SD.

- High temperatures Thursday, Friday, and Saturday will be mostly in
  the 60s and 70s, could be colder if snow remains on the ground.

&&

.UPDATE...
Issued at 830 AM CDT Tue Mar 17 2026

The current forecast is just about as good as it gets, in terms of
covering the potential for light snow to convert to sleet or light
freezing rain throughout and west of the Missouri River valley
this morning as the whole band of precipitation gradually
propagates eastward today. Transient and light precipitation
accumulation potential, so handling "wintry mix" with Special
Weather Statements, in addition to the DSS messaging already in
place, should suffice this morning. Also leaning on potential for
surface temperatures to warm above freezing today and melt any
pockets of light ice accumulation that happens throughout and
west of the Missouri River valley region, where the majority of
wintry mix precipitation accumulation is forecast.

UPDATE Issued at 627 AM CDT Tue Mar 17 2026

Aviation discussion updated below for the 12Z TAFs.

&&

.DISCUSSION...
Issued at 146 AM CDT Tue Mar 17 2026

A warm front will move through central and northeastern SD this
morning through the afternoon along with a line of precipitation.
The precipitation is forecast to start as snow, and then as warm
temperatures aloft start to warm the atmosphere, the snow will melt
into freezing rain/sleet/ice pellets and then potentially rain
through the morning and into the afternoon. The precipitation will
exit northeastern SD late this afternoon into the evening.

Model soundings show the warm air moving in over central SD during
the morning causing higher chances for freezing rain for a few hours
in the morning before precipitation chances move east. The ensembles
have a 20-50% chance for 0.01 inch of freezing rain to accumulate
over central SD and south central SD, with a light glaze possible
for most of these areas. Areas around the James River Valley and
east have cooler temperatures aloft for longer in the morning and
afternoon, allowing for longer times where snow will most likely be
falling. East of the Missouri River could see a light dusting to a
half inch of snow up to an inch and a half over northeastern SD.
There is a 40-80% chance for greater than an inch over and east of
the James River, especially over the Prairie Coteau. Some model
soundings show sleet instead of snow occurring east of the Missouri
River for a bit due to the moisture in the soundings below the
dendritic growth zone, which is needed for snow development. If this
is the case, there could be less snow accumulation or freezing rain
in some areas and more ice pellets/sleet. If the warmer air moves in
faster over central and northeastern SD, then there could be more
freezing rain accumulation and less snow/sleet. Roads and surfaces
could be a bit slick through the day from the light accumulations of
ice and snow. Though depending on how fast temperatures warm at the
surface during the day, the ice and snow accumulations for areas
west of the Prairie Coteau could melt away before the afternoon
commute. To add another threat to watch out for, there could be some
stronger winds from the frontal passage that could cause gusts this
afternoon to get up to 30-35 mph especially over the James River
Valley and Prairie Coteau. If snow is still falling as these winds
are occurring, then there could be some localized areas of blowing
snow and a reduction in visibility during the mid morning into early
afternoon.

An upper-level ridge to the west slowly tries to move over SD during
the end of the week into the weekend. While this ridge is trying to
move over, temperatures warm at the surface. Thursday, Friday, and
Saturday are forecast to be 15-25 degrees warmer than normal, with
some of those days flirting with record highs and record warm low
temperatures. High temperatures during these days could get up into
the 60s to 70s with lows in the 30s to 40s. Precipitation chances
are forecast to stay out of central and northeastern SD until the
weekend. The models show an upper-level shortwave suppressing the
ridge on Saturday/Sunday and helps a surface low move out of
Alberta. This low could then bring some precipitation to the area.
Models vary the chances, timing, track, and location of the
precipitation due to it being 5 days out, leading to lower
confidence in the chances that precipitation occurs in central and
northeastern SD this weekend. An eye will need to be kept on the
models as the weekend gets closer to see if they come to more of an
agreement on what will happen.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 627 AM CDT Tue Mar 17 2026

Terminals KABR,KATY,KPIR,KMBG

CIGs will gradually lower into MVFR from west to east across the
region this morning. -SN/SN will also be spreading eastward over
the region, with IFR/LIFR VSBY. Towards the end of the
precipitation event, there is opportunity for a brief period of
mixed precip for sleet (PL) and/or freezing rain (FZRA).
Improvements to VFR conditions are forecast later in the day.
Low-level wind shear (LLWS) will also be an issue tonight and
inserted mention of this.

&&

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

$$

UPDATE...10
DISCUSSION...12
AVIATION...TMT