156
FXUS63 KABR 260542 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1242 AM CDT Sun May 26 2024

.KEY MESSAGES...

- Unsettled pattern continues with a 20-50% chance for showers and
  thunderstorms mainly south of a line from Wheaton, Minnesota to
  Murdo this evening. Some storms could be strong, especially across
  south central South Dakota.

- 30-60% chance for rain Sunday afternoon through Monday. 20-50%
  chance for rain Wednesday night through Friday.

&&

.UPDATE...
Issued at 1240 AM CDT Sun May 26 2024

The aviation discussion has been updated below for the 06Z TAFS.

UPDATE Issued at 647 PM CDT Sat May 25 2024

Added in some fog tonight across the area given the recent showers
and light winds. Bumped up south central to "areas of fog" for a
few hours in the morning, as well. Based on latest radar trends,
also added pops to Corson and Dewey counties for the next few
hours.

&&

.SHORT TERM /THIS EVENING THROUGH SUNDAY NIGHT/...
Issued at 322 PM CDT Sat May 25 2024

A weak upper level shortwave trough will track across the CWA
tonight, with a more zonal flow setting up on Sunday. Will then see
a somewhat stronger trough approach Sunday evening and track over
the CWA late Sunday night.

At the surface, a boundary associated with a low pressure system
west of the region has set up from southwest to northeast over the
CWA, with southerly flow to the south of it and very light flow to
the north. An abundance of cloud cover along it over the southern
CWA has not allowed for much daytime heating, and therefore not much
in the way of instability. However, 40 to 50 knot of shear will be
in place late this afternoon into this evening, so cannot rule out
the possibility of some shower and thunderstorm development, mainly
south of a line from Wheaton, MN to Murdo. What instability there
will be (1000-1500 J/kg) will be along and south of Interstate 90
corridor, so may see a stronger storm or two there. The
precipitation will exit the area by early Sunday morning. Models are
hinting at the possibility of some lower cloud cover and fog
development late tonight into Sunday morning, but widespread dense
fog is not expected. Will see precipitation chances return Sunday
afternoon across central South Dakota, then spreading east Sunday
night as another boundary tracks from west to east across the CWA.
Instability and shear look minimal with this system, so not
expecting any strong thunderstorm activity.

Low temperatures tonight will be in the mid 40s to lower 50s. High
temperatures on Sunday will be in the upper 60s to mid 70s. Lows
Sunday night will be in the upper 40s to lower 50s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 322 PM CDT Sat May 25 2024

We`ve got a shortwave trough making its way across the region
Monday. Once this moves off to the east, a ridge will move in behind
it and last through Thursday. Thursday evening a low starts to move
into the region and will last through the end of the period.

There will be a couple chances for rain through the period. The
first is Monday morning (20-50%, higher in far northeastern SD and
west central MN) as the trough moves across the area. The next will
be Wednesday evening/Thursday (20-50%) ahead of the next trough.
Storms are possible along with these rain chances with mid level
lapse rates between 7 and 8 C/km and MLCAPE between 100 and 2000
J/kg. Confidence on severe potential is low at this time. Rain
chances (20-40%) will continue through the end of the period.

Temperatures for the first part of the long term will be rising to
around average with highs in the upper 70s to around 80. Once the
rain and trough moves in Thursday evening into Friday, temperatures
will drop a couple degrees into the mid 70s. Winds west river could
become rather strong Monday and again Wednesday with gusts of 30-35
mph possible.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1240 AM CDT Sun May 26 2024

Terminals KABR,KATY,KPIR,KMBG

KPIR is most likely to see some fog development toward morning with
IFR vsby and cigs. However, KMBG and KATY may also see MVFR stratus
develop. All sites are expected to be VFR by noon.

&&

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

$$

UPDATE...Wise
SHORT TERM...Parkin
LONG TERM...KK
AVIATION...Vipond