408
FXUS63 KABR 290527 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1227 AM CDT Sat Jun 29 2024

.KEY MESSAGES...

- The weekend looks dry with 10 to 15 degree below normal
  temperatures expected for both highs and lows.

- The next opportunity for severe storms looks to be organizing
  on Monday as a low pressure system and plenty of moisture will
  move back into the region. Details on timing and threats will
  become more clear in the coming days.

&&

.UPDATE...
Issued at 1225 AM CDT Sat Jun 29 2024

See updated aviation discussion below.

UPDATE Issued at 613 PM CDT Fri Jun 28 2024

The forecast remains on track this evening. No major changes are
planned.

&&

.SHORT TERM /THIS EVENING THROUGH SATURDAY NIGHT/...
Issued at 150 PM CDT Fri Jun 28 2024

At 1 PM CDT, skies are partly to mostly sunny and temperatures are
warming through the 70s. Winds are west or northwest and breezy
(10 to 15 mph with gusts to 25 mph) at times. Isolated (~15%
coverage) to widely scattered (~25% coverage) showers and
thunderstorms have been seen developing along a trof axis/pseudo
warm front across the Dakotas over the past few hours.

Once any ongoing convection dissipates/shifts out of the CWA early
this evening, surface high pressure will take up residence over the
CWA. It looks like there will just be one interruption to that late
tonight/early Saturday morning when a cold front pushes south
through the region. Expect there will be some stratus clouds
associated with that fropa to have to deal with on Saturday. Not
sure how long it will take to burn off the low clouds, but suspect
there will be, at least, a few hours of afternoon/evening sunshine
potential on Saturday. Regardless of whether there is much sunshine
or not on Saturday, the amount of cool, dry air advecting into the
region with this area of high pressure tonight and Saturday (~10C
degrees of cooling noted at 925hpa and 850hpa) should result in high
temperatures only reaching into the 60s to low 70s. Likewise
Saturday night, there shouldn`t be much left for low clouds to
contend with Saturday night while the surface high begins to shift
into Minnesota. A dry airmass, light wind and clear sky night should
end up placing low temperatures down into the 40s to low 50s. These
high and low temperatures Saturday and Saturday night would be
solidly into the 10 to 15 degrees cooler than normal range.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 150 PM CDT Fri Jun 28 2024

A tranquil upper level ridging/surface high pressure pattern will
dominate most of Sunday, however the pattern will change quickly as
we head into the workweek.

Southwest flow aloft ahead a western CONUS long wave trough will
take over by Monday. At the surface return flow winds will set up
and gulf moisture is able to stream northward. By Monday afternoon
models are projecting dewpoints to be back in the mid 60s to low
70s, with corresponding CAPE values ranging from 1000-2000 J/KG
across much of central and eastern South Dakota. Shear profiles will
be deepening. While warm air does spread aloft initially (700 MB
temps 12-14C), capping doesn`t seem to be long lived. Even by 18Z
Monday 500 MB heights will be falling and a pretty distinct
shortwave (although it appears multiple waves of energy may be at
play) will be sliding across the region. Overall, the set up is very
conducive for severe thunderstorm development on Monday afternoon.
As such, our entire region is in the SPC 15% Day 4 risk outlook.
Details on timing and threats should be more apparent in the coming
days.

There could be lingering shower and thunderstorm development into
Tuesday under a passing trough, cold air advection and steep low
level lapse rates. High pressure will make a brief appearance
Wednesday, but won`t last long as the next system moves into the
region Wednesday night and Thursday, continuing the active weather
pattern.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1225 AM CDT Sat Jun 29 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will deteriorate overnight as MVFR stratus moves
in from the north. Cigs are expected to improve to VFR levels by
early afternoon.

&&

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

$$

UPDATE...Wise
SHORT TERM...Dorn
LONG TERM...Serr
AVIATION...Parkin