114
FXUS63 KABR 220847
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
347 AM CDT Mon Jun 22 2026

.KEY MESSAGES...

- Fast moving system overnight tonight comes with a 50/50 chance for
about 1/4" of moisture. Weak thunderstorms are unlikely to produce
severe weather during the overnight hours.

- Marginal Risk (1 of 5) for isolated severe storms Tuesday
afternoon/early evening along and east of the James valley into
western Minnesota. Main threats include wind gusts of 60 mph and
quarter sized hail.

- Temperatures remain near to slightly below normal through the work
week. More seasonal temperatures and humidity return late week into
next weekend.

&&

.UPDATE...
Issued at 347 AM CDT Mon Jun 22 2026

UPDATE for 12Z Aviation update below.

&&

.DISCUSSION...
Issued at 108 AM CDT Mon Jun 22 2026

Subtle kink in 500mb flow suggests subtle wave crosses the area
today. NBM did populate with some blotchy POPs, though not seeing
much in soundings to indicate mid-level clouds or instability aside
from some altostratus in the HRRR/RAP at between 7-10kft and
thats not going to do it.

Focus is mainly on moisture/thunder potential with the wave crossing
the region tonight. Diffluent flow aloft ahead of the wave coming in
across the Norther Rockies to help support thunderstorms during peak
heating across MT/WY with some CAMS supporting isolated convection
in the Western Dakotas.  Aside from the ARW which is generating some
weak convection associated with minor warm advection we`re seeing in
the NAM/GFS/Canadian across the northeast, CAMS keep us dry through
about midnight.  Flow aloft increases to about 50kts, however at
700mb and below its closer to 10 to 20kts. BUFKIT profiles also show
skinny CAPE as the system and warm advection assisted
convection move across the area. This will limit the severe
weather threat as well as intensity of any precipitation. Trends
from the HREF probabilities suggest as such, with most of the
area below a 50/50 chance at seeing 1/4".

Later Tuesday however, 700mb temperatures remain quite mild for this
time of year, dewpoints have increased into the 50s to near 60F.
Flow below 500mb has also increased with the upper low to our north.
Thus its a case of daytime driven instability with unidirectional
shear similar to what we`ve seen for much of early June and
comprises of mainly a wind/hail threat.

Northwest flow aloft continues into Wednesday, however low level
flow is more northerly and surface dewpoints mix out in the 40s
limiting instability. 700mb temperatures are at their coolest
Wednesday/Thursday, after which we see mid level warm advection as
another west to east wave moves into the Northern Rockies. That
system is oddly like the wave from Sunday, and models have it decay
as it moves across the Dakotas. Will wait till it gets closer before
we start talking about moisture probabilities.

Then we look towards the west for a stronger upper low  that drops
into the Pac NW Saturday and traverses the Norther Rockies, lifting
out in Montana and south central Canada Sunday night. A comparison
of 700mb temperatures indicate the GFS has tempered in comparison
to 24 hours ago, while the GEFS has increased to about +12C (1
standard deviation above climo) however these are still higher in
comparison to the Canadian/EC. Also continue to see the return
signal for Gulf moisture as surface dewpoints return well into the
60s.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 347 AM CDT Mon Jun 22 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will dominate at all locations through the
period. The main concern will be at PIR, where MVFR to IFR
ceilings have remained just southwest of the site. The latest
forecast trends have indicated that most of these lower clouds
will remain southwest of PIR. As a result, TEMPO MVFR ceilings
looked most reasonable 13-17Z. Light showers and isolated
thunderstorms are possible overnight, remaining below a 30%
chance prior to 06Z, with a 40-60% chance of showers and a few
thunderstorms prior to 12Z at PIR and MBG.

&&

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

&&

$$

UPDATE...TMT
DISCUSSION...07
AVIATION...06