066
FXUS63 KABR 241908
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
208 PM CDT Sun May 24 2026

.KEY MESSAGES...

- Some isolated to scattered showers and thunderstorms could
  develop or move over portions of east central South Dakota
  and west central Minnesota by early this evening, with rain
  chances persisting over those areas into the early overnight.
  There is a marginal risk for severe thunderstorms, mainly in
  the form of 1 to 2 inch hail potential, this evening into the
  early overnight hours.

- Warming trend in place through mid-week, with temperatures
  persistently above average through the end of the 7-day
  forecast. Highs range in the upper 70s to upper 80s throughout
  the period. Monday and Tuesday could see highs reaching or
  exceeding the 90F degree mark (15 to 20 degrees above normal)
  in some places.

- Isolated to scattered evening and overnight thunderstorm
  chances (20-40 percent chances) exist off and on by Thursday
  evening, continuing into Sunday evening.

&&

.DISCUSSION...
Issued at 204 PM CDT Sun May 24 2026

At 1 PM CDT, skies are sunny and temperatures are warming through
the 70s and low 80s. Winds are generally light from the south around
10 mph with some occasional gusts up to 20 mph. MLCAPE has increased
across the southeastern forecast zones to around 500-750J/kg, and
that is forecast to increase a bit more through 00Z. Deep layer
shear is currently around 35 knots, and may hold around that value
or perhaps drop off to closer to 30 knots by 00Z this evening.

More potential isolated to scattered showers/storms on the low level
jet later this evening and into the early overnight hours, as a
decent low level moisture advection feed continues across portions
of northeast South Dakota and west central Minnesota. There is also
a clearly discernible mid-level shortwave working through eastern
Montana that could serve as some extra-added UVV`s for storm
development on tonight`s low level jet over the region. Between the
available low level moisture/instability and the anticipated 25-35
knots of deep layer shear around tonight, convection that develops
on the low level jet could produce some large hail (1-2in in
diameter). Most of the llj focus/forcing is to the south/east of
this CWA, but SPC`s current SWODY1 does have a small portion of this
CWA`s southeast forecast zones in a marginal risk for severe (mainly
hail threat) weather.

The low level jet eventually points northeast into Minnesota, taking
the low level moisture with it. Conditions on Monday will be much
drier across the Missouri River valley and James River valley
regions, as the next iteration of low level moisture advection that
southerly winds will bring to the CWA do not really appear to ramp
up, in earnest, until after 4-5pm CDT Monday afternoon, with the
best available moisture to generate convection on the nose of Monday
night`s low level jet not arriving until at or after midnight CDT.
Still there could be a storm or two around later Monday night east
of the Missouri River valley, mainly along/north of the U.S. Highway
212 corridor.

By the time Tuesday rolls around, the much talked about upper level
ridge will be squarely overhead, while a west coast upper level
trough is digging in. The potential for mid to late week heat of the
day storms still exists, but hinges on just where the western CONUS
upper low and central CONUS upper ridge sets up in this potential
split flow scenario, as further west positioning makes precipitation
chances better for the central/northern high plains and front-range
areas versus a further east positioning, which would continue the
higher chances for precipitation moreso across the central and
northern plains regions (including a portion of this CWA). And split
flow scenarios several days out in the forecast typically make
forecast confidence in flow pattern details sketchy, at best.
Suffice it to say, there are still couple of 24 hour periods out in
the extended where the QPF ensemble clusters analysis indicates
measurable precipitation possible over the CWA.

There will certainly be a tug-of-war thing going on between the much
warmer air this upper ridge will draw into the region and the green-
up that is occurring. When it`s green and getting greener, the low
level moisture in the boundary layer doesn`t get mixed out quite so
fastly versus when vegetation/trees, etc are brown/dead/dormant and
drying out/heating up the boundary layer is an easier thing to do.
Will watch and see how warm it gets today, and leverage that
information to inform Monday and Tuesday`s forecast high
temperatures.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1212 PM CDT Sun May 24 2026

Terminals KABR,KATY,KPIR,KMBG

Other than a shower or thunderstorm potentially getting within
40 miles of the KATY terminal this evening, good VFR conditions
are forecast through the TAF period.

&&

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

&&

$$

DISCUSSION...10
AVIATION...10