170
FXUS63 KABR 231839
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
139 PM CDT Sun Aug 23 2026

.KEY MESSAGES...

- There is a Slight Risk (level 2 out of 5) across central SD and a
Marginal Risk (level 1 out of 5) along and west of the James River
this evening. The main concerns will be golf ball size hail, wind
gusts exceeding 60 mph, lightning, and brief heavy rainfall.

- There is a Marginal Risk (level 1 out of 5) of severe weather
Monday night. Threat include one golf ball size hail and 60-75 mph
gusts.

&&

.DISCUSSION...
Issued at 139 PM CDT Sun Aug 23 2026

A weak upper level trough of low pressure currently over western ND
still may become the focal point for showers and storms impacting
the western CWA later this evening. A few showers and storms are
ongoing, with some model guidance suggesting modest intensity over
the next few hours. However, the best low level moisture and
instability is located mainly west of the CWA, with SBCAPE exceeding
1K J/kg over western SD. Across much of eastern ND, and northeastern
SD, surface dewpoints in the 50s with limited moisture advection at
this time. As of now, the RRFS is the more robust model solution
with convection developing over the western Dakotas. The storms in
western SD move eastward toward the CWA around 23-0Z before
diminishing. It still maintains a convection complex over southwest
ND moving southward into north central SD after 1Z. The lack of a
LLJ may limit the overall severe threat with the RRFS showing the
storms weakening with time. The past few runs of the HRRR keeps most
of the CWA free from severe weather. Overall, the severe threat is
best west of the Missouri River where a few storms may produce golf
ball size hail and 60-75 mph wind gusts. The pcpn should exit the
CWA before 12Z Monday.

A frontal boundary will cross the region Monday through Monday night
may produce an isolated storm during the day period. Models due
indicate convection developing after 0Z Tuesday, with eastern ND
having a good potential for storms. A lee of the Black Hills surface
low may cause additional storms over central and south central SD.
While widespread severe weather is not anticipated, a stronger storm
or two could produce golf ball size hail and wind gusts of 60 to 75
mph.

After dry conditions midweek, chances for precipitation returns to
the forecast area Thursday night through the weekend. Temperatures
remain at or above average for this time of year.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1211 PM CDT Sun Aug 23 2026

Terminals KABR,KATY,KPIR,KMBG

Prevailing VFR conditions can be expected for all terminals through
the valid taf period. Later this evening, showers and
thunderstorms may track southeastward across the area, with KMBG
having the best potential of seeing thunderstorms. Overall,
confidence remains low with timing and areal extend of
precipitation.

&&

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

&&

$$

UPDATE...17
DISCUSSION...17
AVIATION...17