416
FXUS63 KABR 111230
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
730 AM CDT Tue Aug 11 2026

.KEY MESSAGES...

- There is a Slight Risk (level 2 of 5) for isolated to
  scattered storms for the Missouri valley in the late afternoon
  and evening, and then for the northeast during the overnight
  hours. Main threats include 1 to 2 inch diameter hail and
  wind gusts of 60 to 70 mph.

&&

.UPDATE...
Issued at 724 AM CDT Tue Aug 11 2026

Webcams and satellites have shown some areas of locally dense
fog affecting portions of central and northeastern SD this
morning. An SPS was issued to warn of this fog as visibilities
could cause visibilities to drop to 1/4 mile at times. The fog
is expected to start dissipating in a few hours.

UPDATE Issued at 613 AM CDT Tue Aug 11 2026

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

&&

.DISCUSSION...
Issued at 1245 AM CDT Tue Aug 11 2026

Storms haven`t really panned out very well considering the consensus
among CAMS for the last 24 hours. Warn on forecast still indicates
some development along and southeast of highway 14 over the next
hour or two so we could still be dealing with warnable storms
through the early morning hours. Again, large hail and high winds as
outlined in the previous discussions/updates are the chief concern.

And we`ll try to do it all again later today. Flow remains
northwesterly aloft, with a subtle trough going across the Dakotas
03-09Z. Not much different, with strong unidirectional shear
overall, but weak mid level warm advection and light low level flow
at/off the surface. 1/2km winds are only about 15-20kts out of the
southeast. CAMS are much less organized and more inconsistent in
placement of individual convection. Thus, much lower confidence in
regards to POPs (ie timing & coverage).

Still looks to be a nice shift into cooler temperatures for the
latter half of the work week though overall the upper level flow
regime remains northwesterly. A ridge builds in from the west Friday
as an upper high shifts from 4-corners centric to southeast CONUS,
which may then retrograde back to the west next week. Overall, flow
remains active and its hard to support the elimination of NBM
spammed POPs for any one specific period.

In regards to smoke, not much overall change. Flow aloft will
continue to support high smoke streaming across the region and
helping to suppress temperatures slightly. Low level flow around the
cooler high pressure system mid-week may present a risk but smoke
would have to take a circuitous route as boreal/northern Canada
doesn`t appear to be a source region anymore.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 613 AM CDT Tue Aug 11 2026

Terminals KABR,KATY,KPIR,KMBG

After some sub-VFR low clouds and fog over the region burn off
this morning, VFR conditions are forecast for the rest of the
TAF valid period. Guidance for convection suggests much of the
next 12 hours should be quiet/dry. But, later this evening into
the early overnight hours, there could be a handful of strong to
severe storms around, especially out across and west of the
Missouri River valley region (KPIR and KMBG?). Kept the PROB30s
going for later this evening, and will amend/adjust as needed.

&&

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

&&

$$

UPDATE...12
DISCUSSION...07
AVIATION...10