387
FXUS63 KABR 031833
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
133 PM CDT Wed Jun 3 2026

.KEY MESSAGES...

- There is a Slight Risk (Level 2 of 5) for severe weather this
afternoon and evening, mainly east of the Missouri River. Large hail
of 1-2" in diameter and wind gusts of 60 to 70 mph are the main
threats. An isolated tornado or two will be possible. Additionally,
there is the potential for flash flooding due to heavy rainfall.
Areas west of the Missouri River are under a Marginal Risk (Level 1
of 5).

- Thursday, another Slight Risk for severe weather is in effect
along and south of US Highway 12. Areas to the north of US Highway
12 are under a Marginal Risk. Large hail of 1-2" in diameter will be
the main threat, with wind gusts of 60 mph as a secondary threat.

&&

.DISCUSSION...
Issued at 133 PM CDT Wed Jun 3 2026

As an upper-level low over Saskatchewan moves east today into
Thursday, a cold front will be pushing through central and northeast
SD this afternoon and through the evening. The RAP is forecasting
1500-2000 J/kg of MLCAPE over areas west of the James River during
the afternoon spreading east through the afternoon into the evening.
There is also forecast effective bulk shear values of 40-45kts in
these areas, which will help with the development of supercells.
Discrete supercells look to develop this afternoon between 2-4pm cdt
in areas mainly east of the Missouri River. While these storms are
more discrete, all severe threats will be possible. Mid-level lapse
rates of 7 to over 8 C/km as well as favorable freezing levels are
supportive of significant hail development (2+ inches in diameter).
DCAPE values of 800-1000 J/kg could help get strong to severe winds
to the surface (gusts of 60-70+ mph). Additionally, an isolated
tornado or two cannot be ruled out. Later in the afternoon into the
evening, as the cold front catches up to the storms, the storms look
to become more linear in nature over northeastern SD. These storms
will decrease the significant hail chances, and strong to severe
wind gusts will become the primary hazard. The storms look to move
out of northeastern SD and west central MN after midnight giving the
area a little bit of a break. There is a risk for heavy rains in
these storms as well as some flooding risk. PWAT values, of 1.2-1.4
inches, are above the 90th percentile for the area compared to
climate values. Storms are forecast to not be slow moving, which
does decrease the flooding potential a little bit. However, if
multiple storms move over the same area or there are stronger
storms, then a lot of heavy rainfall could happen and cause the rain
accumulations to add up. Additionally, if storms move over areas
that have recieved lots of rain in the past few days, then the
saturated ground might not be able to hold very much rain and there
could be some flooding potential.

After the storms move through, the rest of the overnight hours will
stay fairly quiet. Calm winds over the James River Valley and other
areas to the east as well as moisture left from the storms during
the evening will lead to the development of some patchy fog. This
fog should dissipate during the morning. During the morning, there
could be some scattered showers and storms that develop over central
SD.

Thursday afternoon into the evening, another front will be moving
through central and northeastern SD. With MLCAPE values in the
afternoon getting up between 1000-2000 J/kg and lingering moisture,
thunderstorms will likely develop during Thursday afternoon into the
evening. Shear values of 35-40kts will help the storms to develop
into supercells or multicell clusters of storms. The SPC has a
slight risk (level 2 of 5) for severe storms to develop south of HWY
12. Lapse rates of 7-8 C/km over central SD will help with the
development large hail as the primary threat, with strong to severe
wind gusts possible as a secondary threat. Higher low level shear
values are currently forecast to stay to the southwest of Jones
county, which will help to limit the potential for tornado
development in central and northeastern SD. While the greatest
severe weather threat will move out of the area during the late
evening, there are still chances for some scattered storm and shower
development overnight into the morning. There is a marginal risk for
some severe storm development over northeastern SD Friday from a
warm front trying to move north into SD, MN, and WI. Northeastern SD
could see some isolated storm development during the afternoon that
could have some hail and wind.

As a small upper-level ridge is forecast to build over SD this
weekend, a surface high pressure will move over central and
northeastern SD. This high pressure will help to keep showers and
storms from developing Saturday. Additionally, with the warm front
Friday, temperatures will get up into 80s to low 90s during the
weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1227 PM CDT Wed Jun 3 2026

Terminals KABR,KATY,KPIR,KMBG

Some scattered showers early this afternoon will lead to some lower
ceilings over KPIR, and KMBG for a bit while other areas will see
VFR to MVFR conditions. There is a slight risk (level 2 of 5) for
severe storms to occur this afternoon over KMBG, KABR, and KPIR and
during the evening for KATY. Once these storms move through,
conditions should get better. Southerly to southeasterly winds will
be possible this afternoon, with gusts of 20 to 30 mph (highest over
KATY). Once a cold front moves through with the storms, the wind
will switch to be coming from the northwest and then become fairly
light and variable into Thursday morning. Additionally, patchy fog
will be possible in the morning, which could decrease visibilities
over KABR.

&&

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

&&

$$

DISCUSSION...BC
AVIATION...12