121
FXUS63 KABR 061149 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
649 AM CDT Mon Jul 6 2026

.KEY MESSAGES...

- A Slight (Level 2 of 5) to Marginal Risk (Level 1 of 5) is in
  place for storms developing this afternoon and evening. The
  main severe threats will be hail of 1 inch in diameter and
  wind gusts of 60 to 70 miles per hour.

- Chances for severe storms return on Tuesday afternoon through
  evening, and a Slight Risk is in place for much of the
  forecast area. All severe threats, including wind of 60 to 70
  miles per hour, hail of 1 inch in diameter, tornadoes, and
  heavy rainfall leading to flash flooding will be possible.

- A slight cooldown is expected Wednesday through at least
  Thursday, with widespread near-normal to just below normal
  high temperatures (low to mid 80s). Signs point to a warming
  trend beginning by the end of the week, and highs may
  potentially hit triple digits over the weekend.

&&

.UPDATE...
Issued at 647 AM CDT Mon Jul 6 2026

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

&&

.DISCUSSION...
Issued at 221 AM CDT Mon Jul 6 2026

Thunderstorm chances return once again today, and a Marginal Risk
for severe weather is in effect for all but south central South
Dakota. Development will be along a cold front, mainly over
northeastern South Dakota into western Minnesota during the evening
time frame. Hail will be a threat with these storms, as CAPE
approaching 3000 J/kg and strong mid-level lapse rates of nearly 8
C/km are in place. Shear is a bit lower than ideal for hail
development, around 30 knots, but that should still be enough to
support severe hail given the other parameters in play. There will
also be a bit of a wind threat, indicated by DCAPE around 1000 J/kg
in model soundings. Confidence is low on the tornado threat tonight,
but can`t entirely rule out a brief spinup along the front.

Tuesday follows up by sporting another risk for thunderstorms, and a
Slight Risk covers most of the area at this time. The aforementioned
cold front will settle in over the area, becoming a stationary front
and providing a source of lift for storms. Both hail and wind will
once again be threats, with the best environment setting up on the
southern side of the front. There is also a bit of an increasing
signal for tornado potential along the front as the evening
progresses. Strong low-level helicity will reach well above 200
m2/s2, and 0-1km shear will increase. With the potential for low
LCLs along the boundary, conditions may line up in such a way as to
support the tornado threat.

With the stationary front settled in across the region, there is
also some concern for flash flooding potential. On paper the setup
doesn`t quite line up with either the traditional Maddox Frontal
Pattern nor the Maddox Synoptic Pattern due to inconsistencies in
both the moisture patterns as well as the shear potential. However,
with the stationary front in play, it is worth discussing
regardless. A number of favorable ingredients are in place,
including a long skinny CAPE profile, PWATs upwards of 1.75" (well
above the 90th percentile for this time of year), moist low to mid-
levels, and a warm cloud layer >10k feet. Cloud layer mean wind and
Corfidi upshear vectors looks to both be a bit high, around 25 to 30
knots. Therefore, looking more towards needing training storms to
realize the flash flood threat. The biggest question will therefore
come down to the strength of the warm air advection riding up along
the front. Model guidance does resolve a roughly 30-40 knot low-
level jet in the 850-700mb layer, but the main question will be
location. The east-west location of the jet is still not quite
clear, which adds to the uncertainty already present from the north-
south location of where the front will line up. Steering winds aloft
will be parallel to the front, adding an additional potential
favorable condition to this setup. At this point, model QPF guidance
shows the highest confidence in northeastern South Dakota and
western Minnesota seeing the highest precipitation totals through
Wednesday morning. This same area is where today`s storms may track,
so will continue to keep an eye on soil saturation as Tuesday`s
event draws nearer.

By Wednesday, the front will complete its journey through the
Aberdeen forecast area, and the pattern aloft will shift to become
more zonal. As a result, temperatures will cool off slightly through
at least Thursday. Highs will be in the low to mid 80s, which is
near-normal to roughly 5 degrees below normal for this time of year.
Beginning at the end of the week, there is a fair degree of
confidence in a warming trend as a broad upper-level ridge takes
hold of the western and central CONUS. The latest NBM guidance gives
areas west of the James River a 30-50 percent chance for high
temperatures to reach triple digits. Of potential interest, the last
time Aberdeen recorded a 100 degree temperature was nearly three
years ago, on July 26th, 2023. Probabilities over the weekend of
Heat Risk reaching major status reach as high as 70% on Sunday,
indicating the potential for widespread heat impacts.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 647 AM CDT Mon Jul 6 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast to prevail through the period.
Showers and thunderstorms will be possible late in the period,
associated with a cold front sliding east-southeast across the
area. The frontal passage should switch winds around to the
northwest, first, at KMBG by early this afternoon, eventually
switching the winds around to the northwest at KPIR and KABR by
the end of the TAF valid period. Currently, guidance holds the
highest chance of convection at KABR and KATY mainly this
evening. PROB30s are now in both the KABR and KATY TAFs as such.

&&

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

&&

$$

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