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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
614 PM CDT Wednesday Jul 29 2015

Short term...(this evening through thursday)
issued at 259 PM CDT Wednesday Jul 29 2015

Very pleasant conditions across the region for late July.
Temperatures have risen into the 80s...with falling dew points
through the afternoon. Winds remain breezy...but remain below
advisory levels.

Overnight...surface ridging will slide across the area. Given lower
dew points and light winds...have lowered overnight lows a bit
further. Would not rule out very patch ground fog...but todays dry
air and wind will take care of most of the surface ground moisture
lingering from recent rains.

Thursday looks to be a tad warmer and slightly more humid...but with
such light winds due to surface ridging...will be nearly perfect day for
July 30th.

Long term...(thursday night through wednesday)
issued at 259 PM CDT Wednesday Jul 29 2015

Friday through the weekend looks to bring a dry and mild regime very
slowly transforming into a more moist pattern...but not an
exceedingly wet one. This somewhat more moist pattern should then
become established for much of next week.

Models bring an increase in instability with the slow moisture
increase by late Saturday. This would lead to a chance of storms
developing during the weekend...with the storms over time tending to
affect the eastern part of the area more than the west. For Saturday
and Saturday night...there is a question about whether or not the
moisture return will be enough for storms to initiate. Will continue
to carry fairly low mention probability of precipitation for now.

Extended guidance seems to go with the ec over the GFS...not an
uncommon event. The GFS has certainly tried repeatedly to build the
upper ridge northward too much. The ec with its flatter pattern of
ridge busting short waves would seem to be the preferred solution
with temperatures getting at most modestly warm and a stronger
threat of storms by midweek...Tuesday night and Wednesday. This is
what the extended guidance comes up with and will go with it for
now. The Gem/Canadian does side with the GFS ridge building solution
so we will see. So far this Summer we have not had the ridge build
strongly enough north to give our area a persistent hot period.
So...the only 90 plus high temperatures in this forecast will be
through the weekend over the western part of the area.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 614 PM CDT Wednesday Jul 29 2015

VFR conditions expected through the period. Lingering afternoon
gustiness will quickly subside near the start of the period...with
light/variable winds overnight becoming northwest around 6-12kts by
middle-late morning Thursday.


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


Short term...dux
long term...

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