Pierre, South Dakota Weather Forecast Discussion

321
FXUS63 KABR 150505
AFDABR
Area Forecast Discussion
National Weather Service Aberdeen SD
1205 AM CDT Mon Sep 15 2025
.KEY MESSAGES...
- There is a 30 to 75 percent chance of showers and a few rumbles
  of thunder across most of the forecast area tonight, (the 50-75
  percent chance is over the Missouri River valley).
- Additional precipitation chances (20-45 percent) return to the
  forecast by early Tuesday evening and persist through Friday,
  before things potentially dry out heading into the weekend.
- Temperatures maintain this potential for being 5 to 15 degrees
  above normal through Tuesday, before things cool down to closer
  to normal from Wednesday through Saturday.
&&
.UPDATE...
Issued at 824 PM CDT Sun Sep 14 2025
Loss of daytime heating has settled things down across the CWA.
There is still a large/vigorous upper low churning across
Nebraska/southern South Dakota. So, expect the forcing/lift from
this upper low to produce more showers/embedded thunder across the
forecast area overnight. The upper low is forecast to move slowly
northward into North Dakota on Monday, which should dry things out
for appx 24 hours while the next system out over the Pac NW head
this way. No significant changes expected to the tonight period
forecast, other than to refine the PoPs/wx mention as needed.
UPDATE Issued at 617 PM CDT Sun Sep 14 2025
See below for an aviation forecast discussion for the 00Z TAFs.
&&
.DISCUSSION...
Issued at 344 PM CDT Sun Sep 14 2025
As of 3 PM CDT, skies are partly to mostly cloudy and temperatures
are in the 80s, except across portions of central/north central
South Dakota where it has been cloudy and raining most of the day.
There, temperatures are only in the 60s and 70s. Radar has shown a
brief lull in returns after the larger area of convection moved out
of north central South Dakota. But, within the past 30-60 minutes
radar coverage has begun to fill back in again. This activity will
have to be monitored for severe potential over the next several
hours. Large hail up to half-dollars, wind gusts up to 60 mph and
even a few brief tornados are all possible during peak heating this
afternoon. The best environment for tornado potential over the next
several hours will be across portions of north central over into
northeast South Dakota where the best low level shear environment
will overlap with the best low level CAPE and lapse rates. Further
east, deep-layer instability is actually closer to 1500-2000J/kg and
low to mid-level lapse rates are little better this afternoon. So,
these storms have a greater potential to produce large hail and
damaging winds. Storm motion is generally around 30 to 40 mph from
the south, so unless storms were to start training again, heavy rain-
inducing flooding may be less of an issue.
During the next 5 or so days, this very blocky pattern will persist,
where a blocking ridge downstream will hold in check longwave
troughiness over the middle of the country. And, with the upper low
that`s over the Nebraska panhandle moving north through the region
tonight into Monday morning, the next upper low over the Pac NW will
move in to the region on Tuesday. Additional upper level troughing
is progged to remain through Friday before the pattern begins to
deamplify. Ensemble PoPs show precipitation chances dropping from 20-
50 percent chances Tuesday through Friday down to 10-25 percent
chances from Friday onward. And, the trend in low level thermal
progs continues to showcase these warmer than climo normal
temperatures hanging on through Tuesday before trending down to
readings closer to normal from Wednesday, onward. Ensemble
temperature guidance is saying the same thing.
&&
.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1205 AM CDT Mon Sep 15 2025
Terminals KABR,KATY,KPIR,KMBG
A mix of VFR/MVFR cigs are expected at KMBG heading into Monday
morning. KPIR/KABR/KATY, for now, are expected to hang on to a
predominantly VFR forecast, with perhaps less of a chance of fog by
morning. There is the potential for showers, and perhaps a few
thunderstorms, overnight into Monday morning, mainly at KMBG.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...10
DISCUSSION...10
AVIATION...10

NWS ABR Office Area Forecast Discussion