989
FXUS63 KABR 301140 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
640 AM CDT Sat May 30 2026

.KEY MESSAGES...

- The Northern Plains will see an active pattern, and chances
  for showers and thunderstorms are in place through the
  weekend and into the start of next week.

- Through Sunday evening, chances to receive 0.5" of rain ranges
  from 20-40% over northeastern South Dakota and western
  Minnesota to 65-85% over central and north central South
  Dakota.

- There is a Marginal Risk (Level 1 of 5) for severe weather
  this evening into tonight across central and parts of north
  central South Dakota. Jones County as well as part of Stanley
  County reach a Slight Risk (Level 2 of 5). Damaging wind gusts
  of 60-70 mph is the main threat. Hail of 1" in diameter and a
  tornado or two cannot be ruled out as possible hazards
  either.

- There is a Marginal Risk (Level 1 of 5) for severe weather
  Sunday, mainly along and west of the James River Valley.
  Damaging wind gusts of 60 mph and hail of 1" in diameter are
  the main threats.

&&

.UPDATE...
Issued at 635 AM CDT Sat May 30 2026

See below for an aviation forecast discussion for the 12Z TAFs.

&&

.DISCUSSION...
Issued at 220 AM CDT Sat May 30 2026

Upper-level trough over the western CONUS brings continued chances
for showers and storms over the weekend and into next week. Through
Sunday evening, ensemble median values range from roughly a quarter
of an inch over northeastern South Dakota and western Minnesota,
increasing to about an inch over central South Dakota. Overall
coverage of showers will be fairly spotty through the weekend and
rain rates light, with the exception of possible thunderstorms both
this evening and Sunday evening. With this setup will also come
strong southeasterly winds, gusting up to 35 miles per hour both
this afternoon and Sunday afternoon.

For today`s severe threat, hi-res model guidance is in a decent
level of agreement on a QLCS system moving into central South Dakota
in the late evening (somewhere in the neighborhood of 03Z). This
helps support the idea that wind will be the main severe threat with
the storms that move into the area. DCAPE in particular highlights
this threat the best, with an area of 1100+ J/kg located over parts
of Stanley/Jones/Lyman Counties. MUCAPE, 0-6km mean wind, and
Effective Bulk Wind Difference will also be sitting near their
preferred thresholds for a QLCS wind threat at 2000 J/kg, 16 knots,
and 20 knots respectively. In terms of the hail threat, not
expecting much with this setup. MUCAPE and decent mid-level lapse
rates of 6.5-7 C/km will be present, but the lack of shear will hold
back the potential for sustained updrafts to create a widespread
hail threat. Shear will also likely be a problem for tornado threat,
as the area will struggle to reach 30 knots of 0-3km shear. LCL
heights and low-level helicity will also be more favorable out
in front of the best shear and CAPE, with perhaps the best
chance of overlap in the best environmental parameters being
over Lyman to perhaps Buffalo county. Therefore, confidence is
low, but can`t rule a tornado out at this point.

Sunday`s severe setup is quite similar to Saturday`s, in that a
plume of CAPE will help support shower and storm development, but
low shear will once again limit potential. High DCAPE values will
once again support a wind threat, and somewhat borderline setups for
hail and tornadoes are once again in place. Currently, a Marginal
Risk is in place for Sunday evening.

Moving into next week, the upper-level low will continue to sit in
place over the western CONUS through until at least mid-week. This
will continue to bring chances for rain through that time frame.
Thunderstorms will be possible next week as well, and some may
become severe. At the moment no setup next week stands out as
necessary to discuss at the moment, and in general expecting
additional borderline setups for severe weather. Outside of
storm chances, little of note is expected in the extended period
other than temperatures holding at near-normal to just above
normal (highs in the upper 70s to low 80s).

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 635 AM CDT Sat May 30 2026

Terminals KABR,KATY,KPIR,KMBG

Prevailing conditions are forecast to bounce between VFR and
MVFR (cigs) at KABR and KATY throughout the TAF valid period.
MVFR/IFR conditions are forecast for the KPIR/KMBG terminals.
Scattered to numerous rain showers will continue to develop and
move north across the region, impacting all four terminals
throughout the period. Expect a couple rounds of thunderstorm
during the TAF valid period, as well. The first round is slated
to work through between ~15Z-21Z, and the second round is
expected later tonight, at or after 03Z. Southeast winds 15 to
20 knots with gusts up to 30 knots will be common at all four
terminals throughout the TAF valid period.

&&

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

&&

$$

UPDATE...10
DISCUSSION...BC
AVIATION...10