998
FXUS63 KABR 200622
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
122 AM CDT Tue Oct 20 2026

.KEY MESSAGES...

- Temperatures today and Wednesday will be 10-20 degrees warmer than
normal, with highs in the upper 60s to mid 70s. Then there is the
potential for temperatures to be 15-25 degrees above normal Thursday
and Friday.

- Dry conditions continue through Thursday with rain chances (30-
50%) potentially returning Friday night into Saturday. Low
confidence in exact track and of the system along with estimated
rainfall amounts at this time.

&&

.DISCUSSION...
Issued at 122 AM CDT Tue Oct 20 2026

An upper-level ridge has moved over SD and it will stick around over
the areas through Thursday. It is helping to support southerly winds
moving warm temperatures into central and northeastern SD.
Temperatures will be between 10-20 degrees warmer than normal today
and Wednesday, with highs in the upper 60s to mid 70s. There is a
small shortwave aloft that will move along the contours of the
ridge. This will push a weak low pressure and front through central
and northeastern SD tonight and Wednesday morning. Luckily, there is
drier air over SD, which will stop the front from developing
precipitation. The only thing one would notice from the front moving
through will be a change in the wind direction. As dry air sticks
around today and on Wednesday, there will be sunny to mostly sunny
skies.

Things will start to change Thursday, as an upper-level trough helps
to push a surface low pressure from NV to the northeast over MT and
then Saskatchewan. While this low pressure will not move over SD, it
will have a couple of fronts that move over the state. Additionally,
it will cause the pressure gradient to tighten over SD as the low
pressure interacts with a strong high pressure over the Great Lakes.
This tight pressure gradient will start to strengthen the winds
aloft that will then mix down to the surface, causing strong
southerly wind gusts to occur. The strongest of these wind gusts
will occur Friday afternoon through Saturday morning. Ensembles show
that there is a 30-50% chance for the winds to gust up to and over
than 45 mph. These winds will need to be watched in upcoming model
runs to see if a wind headline might be needed. These southerly
winds will help to push more warm air into SD, which will increase
the temperatures. The temperatures will be 15-25 degrees warmer than
normal Thursday and Friday, with highs getting up into the 70s to
low 80s. The warmest temperatures will be over south central SD,
with a 40-60% chance that they get over 80 degrees.

The winds are not the only thing that will need to be watched in
upcoming model runs. While this low pressure system will bring our
next chance for rain, the models still vary the timing, track, and
amounts. The models agree that the warm front for this low will be
moving over SD Thursday and stay over the state into Friday. The
models vary when and where rain and potentially storms start to
develop along this front and how quickly the front (and its rain)
moves out. The models then vary when the cold front moves in, when
the rain might develop along it, as well as how long the front and
rain stays over portions of northeastern SD Saturday into Sunday.
There is still a 30-50% chance of precipitation occurring a some
point Friday and at sometime on Saturday, there is just lower
confidence on when and where.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1221 AM CDT Tue Oct 20 2026

Terminals KABR,KATY,KPIR,KMBG

Good VFR conditions are forecast throughout the TAF valid
period.

&&

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

&&

$$

DISCUSSION...12
AVIATION...10