712
FXUS63 KABR 191728 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1228 PM CDT Fri Jun 19 2026

.KEY MESSAGES...

- A couple of areas of light rain migrating east across the
  state this morning. Occasional lightning accompanying the
  precipitation working into Minnesota. Just a few hundredths
  of rain.

- Late Saturday/Sunday widespread rainfall focused across
  central South Dakota. 70% probability for Pierre
  precipitation > 1".

- Temperatures remain near to slightly below normal through next
  week. Coolest day being Sunday at 10 to 20 degrees below
  normal.

&&

.UPDATE...
Issued at 1222 PM CDT Fri Jun 19 2026

Updated discussion for the 18Z TAFs below.

UPDATE Issued at 1013 AM CDT Fri Jun 19 2026

Radar continues to indicate light banded rain tracking west to
east/southeast over south central SD per weak frontogenesis
aloft. HRRR shows the last of this precip moving out of this
area by midday/early afternoon. Otherwise, the SPC has added a
Marginal risk (1/5) for isolated severe storms over
northeastern Roberts County through west central MN as spotty
convective storms are possible here this afternoon through the
early evening. Main threats will be 1" in diameter hail and 60
mph wind gusts with any stronger storm. Of note, surface
vorticity combining with 0-3km ML Cape of 100-200j/kg do overlap
during this time, suggesting cold air funnels or landspouts
could be possible with any weak updraft passing over as NST will
jump between 1-2.


UPDATE Issued at 609 AM CDT Fri Jun 19 2026

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

&&

.DISCUSSION...
Issued at 1252 AM CDT Fri Jun 19 2026

North south band of light precipitation migrating across the
northern half of the CWA early this morning. Just seeing a few
hundredths of moisture and a wind shift to west northwest.

The upper pattern starts with a broad/shallow trough to the east and
northwest flow aloft. This shifts east, with a weak ridge aloft
migrating in from the west out ahead of a wave that crosses the
Northern Rockies late Saturday/Sunday.  Thats followed by another
northwest flow trough, another bump in the flow for late in the week.
This does two things for us: 1) keeping the mid/low levels cool:
700mb as cool as +2C to -2C Friday and as warm as +2 to +8C Sunday.
Forecast highs in the 70s. And 2) temperate dewpoints, from 40s to
as high as mid 50s.

Departing convection migrates east this morning, but in its wake,
limited/shallow instability is showing up in the BUFKIT profiles.
Could be some daytime driven storms along the eastern/southeastern
periphery of the CWA but more favoriable conditions exists to the
east. High pressure extends southeast out of Montana ie. mild
temperatures and low dewpoints Today.

The wave for late Saturday/Sunday features more synoptic driven mid
level moisture as opposed to surface based convective instability as
the source for precipitation. Mean NBM precipitation highlights
central/south central South Dakota with a mean peak of close to 2
inches and a 25th/75th range of between 0.75" to 2.25". Up across
the north central/northeast, the values are much lower with a mean
of about 0.75" for Mobridge, 0.25" for Aberdeen/Watertown and
nothing for west central Minnesota. Uncertainty in the exact track
means the northern tier is on the edge between higher amounts and
essentially nothing. This means the broader range for the 25th/75th
percentiles being nothing for the low end at
Mobridge/Aberdeen/Watertown etc, and a higher bound of 1.5" for
Mobridge and 0.5" Aberdeen/Watertown, though west central Minnesota
maintains an upper bound of just a few hundredths.

This main reason for the high range of outcomes in the northern
extent of rainfall is evident in NAM BUFKIT profiles, a dry subcloud
layer. This is due to high pressure to the north feeding drier air
into the system.

The next northwest flow shortwave that follows moves through late
Monday/early Tuesday. Environment here is again, skinny CAPE and
unidirectional flow, albeit not very strong.

See below for an update to the Aviation/06Z TAFS discussion...

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1222 PM CDT Fri Jun 19 2026

Terminals KABR,KATY,KPIR,KMBG

VFR cigs are forecast through the end of the TAF period at all
terminals. Winds will continue out of the northwest, with gusts
of 20-30kts this afternoon through the evening and diminishing
as a high pressure system moves into the region and becoming
light and variable overnight. Winds will prevail out of the east
and southeast for Saturday with gusts of 20kts over KPIR by the
afternoon

&&

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

&&

$$

UPDATE...MMM
DISCUSSION...07
AVIATION...MMM