512
FXUS63 KABR 060627
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
127 AM CDT Sun Sep 6 2026

.KEY MESSAGES...

- There is a Marginal risk (level 1 out of 5) for severe storms over
portions of north central SD and northeast SD into west central MN
this morning into the evening hours. Main hazards will be 1 inch in
diameter hail and 60 mph wind gusts.

- There is a Marginal risk (level 1 out of 5) for severe storms over
central and northeastern SD and west central MN Monday. The primary
hazards will be 1 inch in diameter hail and 60 mph wind gusts.

- Hot temperatures for September will persist into Monday. Highs in
the low 80s over northeastern SD to mid 90s over central SD are
expected for the next couple of days.

- Northwest wind 15 to 30 mph and gusts of 30 to 45 mph, low
relative humidity, and dry cured fuels may result in fire weather
concerns on Tuesday.

&&

.DISCUSSION...
Issued at 126 AM CDT Sun Sep 6 2026

The upper-level ridge continues to sit over SD today and into
Monday, with multiple rounds of shortwave moving over the state
during that time. At the same time, a surface trough continues to
sit over western SD with an attached stationary front stretching from
northwest to southeast SD. Scattered showers and storms look to
continue to develop as the shortwaves move over the boundaries this
morning through Monday morning. Some models are hinting at showers
and storms developing early this morning from a low level jet, which
then move into northeastern SD where they continue to stay into the
early afternoon. CAPE values in northeastern SD this morning into
the afternoon will be between 1000-3000 J/kg, which will help with
the continue development over the area as the low level jet and
shortwaves provide some upper-level support. With very little shear
over northeastern SD, the storms will have a hard time becoming
supercellular and severe. However, with stronger lapse rates, they
could develop hail and some strong winds. There is a marginal risk
(level 1 out of 5) for these storms to become severe, and if they
do, the wind gusts could get up to 60 mph and hail up around 1 inch
in diameter.

The warm, moist air moving in today will help to support the storms
this morning and early afternoon, as well as helping to warm the
temperatures at the surface and aloft. 850 temperatures this
afternoon and evening will be between 20-24 degrees C, which will
help to place a decent cap over central and northeastern SD. This
cap will help the early afternoon storms to taper off and keep
strong storms from developing late this afternoon and into the
evening, though there could be some weak scattered pulsy showers and
storms that develop and try to break through the cap. As
temperatures cool slightly overnight into Monday morning weakening
the cap, as well as another nocturnal low level jet developing over
central and northeastern SD, some more isolated showers and storms
could try to develop overnight into Monday morning. While there will
be some instability to help them develop, the stronger lapse rates
and shear will not be there to help them become severe.

An upper-level low and trough over the Pacific Northwest will be
pushing east Monday and Tuesday, which will finally cause the ridge
to move out of the state Monday night. This upper-level trough will
be supporting a cold front pushing through SD Monday night. This
front will be moving into an environment that has had warm, moist
air being pushed into it through the day. The NAM shows CAPE values
of 1000-3000 J/kg building over central and northeastern SD through
the day. Storms will be able to develop as the front moves through
late Monday afternoon into the nighttime hours. Lapse rate values of
5-7 C/km as well as shear values of 30-40 kts could help hail and
strong winds to occur in the storms that do develop. There is a
marginal risk (level 1 out of 5) for storms to become severe, with
the primary threats of 60 mph wind gusts and hail up around 1 inch
in diameter.

Early Monday morning and through the day, as the front is
developing, the pressure gradient over SD strengthens. This will
cause the winds to strengthen aloft and get to the surface as the
lapse rates start to pull the winds down during the day. Winds will
pick up during the afternoon, with models showing a 30-50% chance
for gusts to be above 40 mph Monday afternoon over portions of
northeastern SD. The winds look to pick up again Tuesday over north
central SD with a 40-60% chance for gusts the get above 45 mph.
These winds, as well as the relative humidity, will need to be
watched over the coming days to see if the models continue to show
strong winds and lower humidity. If it does, there could be some
wind and fire weather concerns. Temperatures behind the front will
cool to be around normal for this time of the year Tuesday and
Wednesday. Highs Tuesday look to be in the 80s and highs Wednesday
in the 70s.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1233 AM CDT Sun Sep 6 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast to prevail for the start of the TAF
period. Closer to 12Z Sunday, MVFR/IFR CIGs may try to make
their way into the KATY region. Also, SHRA/TSRA are possible
across the region Sunday morning, mainly over eastern SD
(KABR/KATY). Due to low confidence on areal coverage and
location, will handle this with PROB30 groups for the time
being.

&&

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

&&

$$

DISCUSSION...12
AVIATION...TMT