544
FXUS63 KABR 211141
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
541 AM CST Fri Nov 21 2025

.KEY MESSAGES...

- Fog will continue over mainly central SD this morning, with
pockets of dense freezing fog where visibilities fall below half a
mile.

- High temperatures will be 5 to 15 degrees above normal
through Monday, in the 40s and 50s. Saturday and Sunday will be the
warmest days.

- Turning markedly colder starting next Tuesday, as temperatures
drop into the teens at night and 20s and low 30s during the day.

- There is a 20-45 percent chance of precipitation starting Monday
morning through Tuesday. The precipitation type will be rain Monday,
before transitioning to snow during the day Tuesday.

&&

.UPDATE...
Issued at 541 AM CST Fri Nov 21 2025

A Dense Fog Advisory has been issued for much of the area
near/along the MO River, as pockets of 1/4 or less visibility have
developed. Temperatures below freezing and the low visibility will
create the potential for light icing in freezing fog. A Special
Weather Statement has been issued for much of east central SD.
While there are pockets of dense fog, it looks to be more
localized in coverage.

&&

.SHORT TERM /TODAY THROUGH SATURDAY AFTERNOON/...
Issued at 258 AM CST Fri Nov 21 2025

A look at the latest surface weather map shows 1018mb high pressure
over eastern SD through western MN and northern IA. There were a
couple areas of low pressure, along the southern
Alberta/Saskatchewan border and across southern KS. We have high
clouds streaming north from the low to our south. Otherwise, with
few high clouds and plenty of low level moisture, and light winds,
we do have pockets of reduced fog. The thickest fog has been near
the MO River. PIR has been jumping from 7 to 1/2 mile visibility
since 06Z as waves of fog move over the airport. A more steady fall
of visibility was noted at ATY, down to around 2SM by 0838Z. We will
continue to monitor the progression of the fog, as temperatures
below freezing and low visibility could result in freezing fog with
a light icing. At this time, the most likely location for fog at or
less than 1/2mile will be over Lyman County in south central SD.
Fog/reduced visibilities will slowly improve from daybreak through
the rest of the morning hours.

The surface high will shift east-southeast and reside over southern
MN/northern IA by 21Z as the Canadian low moves across southern
Saskatchewan. The northern low will push a warm front across central
and eastern SD tonight. 850mb temperatures will briefly jump up to 8-
10C by 09Z Saturday, before a cold front sinks in from the
northwest. Winds will increase Saturday afternoon, out of the
northwest with gusts 15-25mph. While colder air will be behind the
cold front, the 850mb temperatures will still be around 4-6C during
the day Saturday (with the coldest air around 0C staying over
northern MN - closest to the surface low and 500mb shortwave). Dry
weather will continue, with highs in the upper 40s and 50s.

&&

.LONG TERM /SATURDAY EVENING THROUGH THURSDAY/...
Issued at 258 AM CST Fri Nov 21 2025

Saturday night into Sunday, split upper-level flow over SD will have
an area of higher surface pressure over SD. This high pressure will
keep winds lighter over central and northeastern SD and
precipitation out of the area. Additionally, the higher surface
pressure, as well as some mid to low level WAA, will keep
temperatures about 15-20 degrees warmer than normal for this time of
the year, up in the 50s. This warmer than normal weather we have
been having will not be around for much longer as colder air is
forecast to move in Monday night. This will cause temperatures to
drop to be around normal by Tuesday and 5-10 degrees colder than
normal by Thursday.

This drop in temperatures will be because a surface low
pressure/surface trough is moving towards and through SD Monday into
Tuesday, though the models do vary the location and timing/track of
the lower pressure. This variability in the low pressure track and
timing also causes differences in precipitation timing and location,
as some models have the precipitation moving into the area later
than other models as well as if there is any wrap around
precipitation chances. This leads to up to 40% chance for
precipitation moving into south central and northeastern SD Monday
morning/afternoon though the area by early Wednesday morning. The
warmer temperatures Monday will cause the precipitation to stay as
rain through the day. Then the cold air moving in behind the low
pressure will help to transition the rain to a rain/snow mix Monday
night/early Tuesday morning into mostly snow Tuesday. Ensembles are
showing a 30-40% chance for greater than an inch of snow to occur
over the Prairie Coteau by Wednesday afternoon, with around/less
than a 20% chance for an inch of snow over central and the rest of
northeastern SD. The cold air advection will also help to bring
stronger winds to the surface Monday evening and Tuesday. With the
stronger winds occurring while snow is falling, there is a chance
for blowing snow to happen in areas of higher elevations, such as
the Leola Hills and the Prairie Coteau. This blowing snow could
cause localized visibility reductions in some locations and make
travel a bit more hazardous.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 541 AM CST Fri Nov 21 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to remain at ABR. Dense fog has moved
into ATY, MBG, and PIR with LIFR visibility and ceilings.
Temperatures below freezing is resulting in light icing being
reported at the ASOS locations. Expect the fog to mix out/lift
with VFR conditions returning by 18Z at all locations, with the
fog lingering the longest at PIR.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Dense Fog Advisory until 10 AM CST /9 AM MST/ this morning for
     SDZ009-015-016-033>035-045-048-051.

MN...None.
&&

$$

UPDATE...06
SHORT TERM...06
LONG TERM...12
AVIATION...06