291
FXUS63 KABR 271951
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
251 PM CDT Wed May 27 2026

.KEY MESSAGES...

- Isolated showers and storms will be possible this afternoon
  into early evening. This activity will remain sub-severe with
  only small hail and locally heavy downpours the main threats.


- High temperatures through the end of the week will remain in
  the upper 80s to mid 90s(15 to 20 degrees above normal).
  Slightly cooler air will filter in this weekend into early
  next week but still remain above normal.

- Increasing chances(30-70 percent) for showers and thunderstorms
  will be possible this weekend into early next week.

&&

.DISCUSSION...
Issued at 250 PM CDT Wed May 27 2026

Early afternoon conditions across the forecast feature a mostly
sunny sky across central SD while northeast SD and west central MN
are seeing more mid to high level clouds. A relative light to
moderate wind has been the going trend today as temperatures have
warmed into the mid 80s to low 90s. Upper level ridging is
positioned right over the top of the area and has "trapped" this mid
level moisture as it continues to wobble around underneath and
remains the impetus for future enhancement as instability builds
through the afternoon. CAM`s continue to hint that more development
of isolated showers and thunderstorms this afternoon across
northeast SD/west central MN. MLCAPE values of 1000-1200 J/kg are
forecast from the RAP13 through late afternoon along with the
presence of a stationary frontal boundary draped northwest to
southeast across our eastern zones should be enough to focus any
convection across these areas. Deep layer shear is rather meager if
non-existent, so anything that does get going should be short-lived.
Most of the activity will be sub-severe with any of the strongest
cells capable of producing small hail and locally heavy downpours.

The upper ridge will remain planted over the eastern Dakotas and
western MN tonight through most of Thursday. CAM`s hint that the
isolated convection may persist into the early to mid evening hours
before coming to an end. Dry conditions overall are expected
overnight as temperatures only fall to around 60 degrees, which is
about 10 degrees above normal. That stationary front will lift north
and east toward the Dakotas/MN border area by the end of the day
Thursday. Another hot day is expected Thursday as 850mb temps are
progged top out around +20C across most of the forecast area. This
will give us another day of low to mid 90s for highs which is 15-20
degrees above normal for late May. There are a couple of CAM
solutions that want to generate a couple of isolated showers or
storms Thursday afternoon across parts of central/northeast SD.
However, ML CAPE values are progged to be lower than today`s progs
and shear will remain rather non-existent plus soundings show quite
a deep and dry sub-cloud layer. So for now, we`ll keep the forecast
dry for Thursday.

A weakness on the western fringe of the upper ridge will lift north
into the Northern Plains by late Thursday into Friday. This will
begin to introduce low to mid level moisture back into parts of the
region by the end of the day Friday and into the upcoming weekend.
Model inconsistencies remain in placement and timing of any showers
and thunderstorms the latter half of Friday into Saturday, although
enough guidance does tend to favor our western zones for seeing
precip during this time. A more organized upper trough is progged to
shift northeast out of the Great Basin and into the Northern High
Plains on Saturday into Sunday. Lee troughing with perhaps a sfc low
anchored on said boundary is progged to shift into the western
Dakotas during the second half of the weekend. This should provide
for more widespread precipitation chances for a larger portion of
our forecast area by Sunday into early next week. Questions still
remain on the longevity of this more active pattern. The GEFS/GEPS
camps reassert upper level ridging across the region by next Tue/Wed
while EC ENS maintains upper troughing across the Dakotas during
that time frame. In house ensemble approach will continue to broad-
brush low end PoPs late in the forecast period.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1224 PM CDT Wed May 27 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue to prevail at all TAF sites through
this forecast period. Still expecting the development of a few
SHRA`s/TSRA`s late this afternoon into this evening across
northeast SD. Coverage of this activity is expected to remain
isolated so not confident enough to add mention of this to the
KABR/KATY forecasts at this time.

&&

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

&&

$$

DISCUSSION...Vipond
AVIATION...Vipond