Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 241127 AAA

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
627 AM CDT Sat Jun 24 2017

Issued at 622 AM CDT Sat Jun 24 2017

See updated aviation discussion below.


.SHORT TERM...(Today through Monday Afternoon)
Issued at 339 AM CDT Sat Jun 24 2017

Skies are clear across the CWA with mainly light winds. Favored cold
spots are really seeing temps tank, with ABR sitting at a new record
low of 40 degrees with a couple hours of cooling left. Also watching
the compact upper low moving southeast across eastern ND. Band of
clouds and light showers is moving southeast across south central
ND, approaching the ND/SD border. Based on upstream radar activity,
have moved POPs back to the west for the morning hours and increased
POPs slightly over the far eastern CWA. This upper low will bring a
reinforcing shot of cool air, especially for eastern areas. Highs
will be well below normal with readings only in the low to mid 60s
over the far eastern CWA. Warmer temps aloft and good mixing will
allow western areas to reach the low 70s.

For tonight, surface high settles over central SD with light winds.
Sided towards the colder end of guidance in this scenario, which
brings lows down into the upper 30s and low 40s - another chilly
night in store. Will have to watch cloud trends though, as models
indicate there may be some degree of cloud cover moving into the CWA
by sunrise which would mess up lows just a bit. For now though, went
towards the colder end of guidance given the surface high placement.

A weak disturbance within northwest flow aloft may bring a few
showers across the area Sunday afternoon, so have expanded POPs a
bit more than SuperBlend based on some of the latest model output.
Otherwise, looking for another surface high sliding down into the
area Sunday night through Monday, bringing dry/quiet conditions with
mainly light winds.

.LONG TERM...(Monday Evening through Friday)
Issued at 339 AM CDT Sat Jun 24 2017

The extended period begins with an upper level trough over the
eastern part of the country, and ridging over the west. The ridge
begins to work its way east Monday night, becoming centered over the
Plains region Tuesday morning. By Tuesday evening, a more zonal flow
pattern develops, and remains dominant through early Thursday when a
weak trough develops and slowly pushes across the region through the
end of the period. Will see a few periods of shortwave energy move
through, mainly Tuesday night and Wednesday, and again late Thursday
into the day Friday.

At the surface, high pressure over the area Monday night will exit
to the east on Tuesday as low pressure approaches from the west.
Will see precipitation develop ahead of and along the frontal
boundary Tuesday night into Wednesday. MUCAPE values of 2500-3500
j/kg and shear values of 35 to 45 knots, along with a 50-60 knot LLJ
will likely result in strong, to potentially severe, storms Tuesday
night and again Wednesday afternoon. Additional precipitation
chances during the latter half of the period will likely just be
some general showers and thunderstorms as instability and shear will
be lacking with a second low pressure system set to track across the
Central Plains.

The warmest temperatures of the period will be Tuesday and Wednesday
with WAA in place ahead of the approaching front. Generally looking
at highs in the 80s and 90s Tuesday, and in the 80s on Wednesday
before cooler highs in the mid 70s to lower 80s occur Thursday and
Friday. Overnight lows will be mainly in the 50s.


.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 622 AM CDT Sat Jun 24 2017

VFR conditions will prevail across the area today and tonight.
Scattered rain showers are possible this morning into the early
afternoon hours across the northeastern portion of the CWA. Also,
look for northwest winds in the 15 to 30 knot range from mid
morning through the early evening hours.




LONG TERM...Parkin
AVIATION...Parkin is the U.S. government's official web portal to all federal, state and local government web resources and services.