788
FXUS63 KABR 200101
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
701 PM CST Wed Nov 19 2025

.KEY MESSAGES...

- High temperatures will be in the 40s and 50s through next
  Tuesday, which is around 5 to 10 degrees above normal. Warmest
  temperatures will be this weekend.

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

&&

.UPDATE...
Issued at 656 PM CST Wed Nov 19 2025

Just a quick update to add dense fog to two areas, one up east of
Mobridge to Eureka, the other just west/south of Pierre into Murdo
and parts of I-90 in Jones/Lyman. These are fairly small areas
overall, and separated by 40 miles (Sully/Hughes counties) so at
this time considered too localized for a dense fog advisory
despite visibility down to 1/4 mile on webcams. Additionally, its
fairly rare to have have dense fog on a northwest component.
Expect it will transition to the southeast with the mean flow this
evening/overnight.


UPDATE Issued at 530 PM CST Wed Nov 19 2025

See below for an update to the aviation discussion...

&&

.DISCUSSION...
Issued at 139 PM CST Wed Nov 19 2025

At 1 PM CST, skies were a mix of sun (central South Dakota) and
clouds (north central/northeast South Dakota and west central
Minnesota). Been mixing out low clouds and patches of (dense at
times) fog today underneath what had been a blanket of earlier
mid/high clouds. Temperatures have been warming out of the 30s
through the 40s, with a few locations (central South Dakota)
starting to run up into the 50s. Except for the far western (west
river) counties where a west-northwest wind has developed early this
afternoon, winds continue out of the south around 10 to 20 mph with
some occasionally higher gusts.

The wind-shift responsible for turning the wind around to a west-
northwest direction will make it`s way over into Minnesota during
the evening hours, with an area of surface high pressure building
into the region behind it overnight. This high pressure is forecast
to stick around Thursday and Thursday night, yielding dry, light
wind conditions, and temperatures a little bit cooler for Thursday,
with highs only expected in the mid 40s to around 50 degrees (about
5 to 10 degrees cooler than today`s expected highs, but still
roughly 5 degrees above climo normals for mid-November).

The long term period is a split flow pattern, where the northern
branch jet-stream is a low amplitude upper level ridge over the
northwest/north central CONUS from Friday through next Monday. There
is general agreement amongst model camps for a longwave trof to work
through the northern branch jet-stream and knock the ridge down
across southern Canada and the northern plains from Monday night
through the end of the forecast period. This upper level trof is
expected to drop and drag a potent cold front through the CWA
somewhere between 12Z Tuesday and 12Z Wednesday. With an upper level
closed low drifting out of the desert southwest into the deep south
Saturday through Monday, there is some doubt over whether any Gulf
moisture will make it past the southern U.S. system, and be
available to generate WAA-zone forced light precipitation (over this
CWA) with this northern branch system Tuesday/Wednesday. Suffice it
to say, the change in airmasses with this cold fropa next week will
be quite noticeable. Instead of high temperatures being in the 40s
and 50s, highs will only be in the 20s and 30s starting next
Wednesday. Low temperatures are expected to transition from 20s and
30s down into the teens (possibly single digits) above zero.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 530 PM CST Wed Nov 19 2025

Terminals KABR,KATY,KPIR,KMBG

We have one layer of MVFR/IFR stratus that ensconces KABR/KATY, a
smaller area of IFR CIGS out by KPIR, and a third small area of
IFR CIGS/Fog by KMBG, while just to the northwest of KMBG a layer
of MVFR stratus. As we proceed through the TAF period, the low
CIGS impacting KABR/KATY will shift to the north. Then the stuff
in North Dakota will take over for KMBG/KPIR. That then continues
east to eventually impact KABR/KATY. The time between status
layers for KABR may be very short indeed, but a little longer for
KATY which will have a discernible period of VFR conditions. This
low moisture is expected to stick around into the day Thursday.


&&

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

$$

UPDATE...07
DISCUSSION...10
AVIATION...07