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fxus63 kfsd 201114 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
614 am CDT Tue Aug 20 2019

Short term...(today and tonight)
issued at 230 am CDT Tue Aug 20 2019

Abbreviated discussion tonight with active ongoing weather...

Persistent altocumulus castellanus thru the evening has finally enhanced across northwest
Iowa as better focus of the low level jet has helped finally overcome some
inhibition. Large hail would be the primary concern with ample
elevated instability/steep mid level lapse rates with some
indication in the cams of organization into bowing structures as
it move southeast of our area and thus a transition to wind with
substantial dcape.

Any remaining activity should clear the area by the mid morning
hours with fairly quiet weather expected the remainder of the day.
Cold front will push thru the area although should come thru dry.
This will lead to some bump in the winds though with fairly good
pressure packing ahead of it.

By the evening, surface front should be south of our area into
Nebraska by the evening hours but enough elevated instability
remains right along the MO River Valley as the wave slides eastward
that some thunderstorm activity may clip areas along the South Dakota/NE
border and then into northwest Iowa. Evening high res guidance even shows
some northward trend in the shower activity and thus nudged slight
chance pops northward some but may need to do so even more if trends

Long term...(wednesday through monday)
issued at 230 am CDT Tue Aug 20 2019

Some lingering showers are possible across northwest Iowa into Wednesday
but otherwise cooler and drier air, along with clearing skies will
work in from the north. Mid level ridging builds to our west by
the middle of the week and will allow for mostly quiet and dry
conditions thru the end of the work week. By the weekend, an
elongated shortwave moves into the central US and will bring our
next chance of showers and thunderstorms. Temperatures thru the
extended look to range generally range from the mid 70s to mid 80s
with the coolest day looking to be the Post-frontal day of


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 608 am CDT Tue Aug 20 2019

The last remaining storms continue to push out of our area thru SW
Minnesota and northwest Iowa with MVFR to LIFR stratus building in behind it. This
is/will likely impact all 3 terminals thru mid morning before
guidance is in fairly good agreement of these ceilings
diminishing. Otherwise cold front will continue to work thru the
area today and turn winds more northerly. Overnight, showers and
thunderstorms may work toward the MO River Valley with ksux
standing the best chance of seeing this activity.


Fsd watches/warnings/advisories...
South Dakota...none.

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