195
FXUS63 KABR 152332 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
632 PM CDT Tue Sep 15 2026

.KEY MESSAGES...

- Dry conditions expected today before a weak disturbance
  tracks over the region Wednesday morning into the afternoon,
  bringing the opportunity for isolated to scattered showers and
  weak thunderstorms.

- Another round of rainfall is expected late Thursday through
  Friday. The highest accumulations are expected over eastern
  South Dakota, where probability to see an inch of rain or more
  ranges from 40-60%.

&&

.UPDATE...
Issued at 625 PM CDT Tue Sep 15 2026

Aviation discussion updated below for the 00Z TAFs.

&&

.DISCUSSION...
Issued at 144 PM CDT Tue Sep 15 2026

As high pressure keeps moving over central and northeastern SD
today, it will help to keep showers and storm chances out through
tonight. Skies will be staying mostly clear through the remainder of
the day and into the night, which will help the temperatures tonight
drop into the low 40s to low 50s. Humidity will stay fairly high
through the night, and with light winds and fairly saturated soils
from yesterday`s rain, there could be patchy areas of fog that
develop over areas east of the Missouri River. This fog will be more
localized and should not go below a mile in visibility.

An upper-level shortwave will be moving over SD early Wednesday
morning into the afternoon. This will help some stronger winds aloft
to move in central SD tonight. As this low level jet moves over,
some warm, moist air moving into central SD will start to develop
some isolated to scattered showers and storms early Wednesday
morning. As the low level jet moves east through the morning into
the afternoon, it will continue to cause these scattered showers and
storms over central and northeastern SD. These showers and storms
will be fairly weak and will not become severe. Rain amounts from
these showers and storms look to not be a lot, with only a 20-40%
chance for 0.1 inch or more rain to fall mainly over north central
SD.

The low-level jet will stick around over central SD through the
morning and into the early afternoon. While early in the morning the
lapse rates will be weaker and it will be harder for the stronger
winds to mix down, through the morning and into the afternoon the
lapse rates will increase, causing stronger winds to get to the
surface over central SD. Ensembles show a 40-80% chance for winds to
gust up around and over 35 mph over areas west of the Missouri
River, and a 30-50% chance for winds to gust up around and over 40
mph over Corson and Dewey counties. These winds speeds are strong
but they do stay below wind advisory criteria for now. Relative
humidity values will stay around and above 50% in the locations and
around the time of the strongest winds. This helps to keep the fire
weather concerns lower for Wednesday.

The next chance for accumulating precipitation will start Thursday
afternoon through Friday as a warm front and surface low pressure
moves in and towards central and northeastern SD. Models are still
varying the location of this low and frontal boundary as well as dry
air moving into northeastern SD Thursday evening into Friday. This
causes different outcomes in the location and timing of showers and
storms moving through SD. A majority of the models are showing the
precipitation moving through mainly south central SD to the east
over portions of east central and southeastern SD, with the bulk of
the rain occurring over eastern SD. However, some models have the
area of rain more to the north or to the south, leading to lower
confidence in the location and some of the timing of the showers and
storms. Depending on where the showers and storms end up, as well as
how much dry air mixes in, the rainfall amounts vary as well. Some
models have chances for 1-3 inches over central and northeastern SD,
with the highest amounts over eastern SD. However, other models keep
the values lower, with 0.5-1 inch of rain possible. This is
something to keep an eye on as more model runs come to more of an
agreement. Either way, there is currently a marginal to slight
Excessive Rainfall Outlook for portions of central and northeastern
SD, with the highest chances of flooding potential to the southeast
of the area.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 625 PM CDT Tue Sep 15 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are currently forecast through the TAF period.
There is a slight chance (~20%) for -SHRA/SHRA across the region
on Wednesday. Not confident enough to even mention a PROB30 at
this time, but if one of these showers were to move over a
terminal, brief MVFR VSBY is possible, while CIGs should
generally remain VFR.

&&

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

&&

$$

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