FXUS63 KABR 240518 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1218 AM CDT Mon Aug 24 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.

&&

.UPDATE...
Issued at 856 PM CDT Sun Aug 23 2026

Severe storm activity has been confined to northwest SD this
evening as cells continue to move south-southeast over UNR CWA.
Will maintain small PoPs (20-30%) across the western CWA this
evening, but even this might be a bit overdone.

&&

.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 /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1217 AM CDT Mon Aug 24 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to prevail through the next 24
hours. 

&&

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

&&

$$

UPDATE...TMT
DISCUSSION...17
AVIATION...20