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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
121 am CDT Monday Aug 3 2015

issued at 115 am CDT Monday Aug 3 2015

See below for an updated aviation forecast discussion.

Update issued at 726 PM CDT sun Aug 2 2015

Very pleasant evening across the region...with mainly clear
skies...low humidity...and just a light breeze. Surface high
pressure will continue to drop southeastward into the region overnight. As
winds decouple after sunset...expect readings to quickly fall into
the 60s by 10pm. Overnight lows will be rather cool...with
readings in the lower 50s to around 60f.

Keeping an eye on an area of smoke on visible satellite this evening
over Montana. With prevailing flow at 700 mb and 500 mb out the the
northwest..expect this smoke to gradually overspread the region
on Monday...resulting in that hazy...milky white appearance to the



Short term...(this evening through Tuesday night)
issued at 233 PM CDT sun Aug 2 2015

A ridge of high pressure at the surface is building southward across
the County Warning Area...and will continue to influence the area overnight and
through the day Monday. This will bring dry conditions...mostly
sunny skies and fairly light winds. This high will continue to bring
these conditions largely into Monday night even...but will also
begin watching an area of low pressure forming over the High Plains.
As we head into Tuesday and Tuesday night...shortwave energy begins
tracking eastward across the Dakotas while the surface trough also moves
east. Still some differences noted in the models...mainly in regards
to the strength of the surface low. A few models are showing an actual
closed low at the surface moving through while others feature more of a
broad trough of low pressure oriented north to south. For now have
probability of precipitation highest across central South Dakota Tuesday into Tuesday night...with
chances increasing further east into Wednesday. These may need to be
refined based on any changes in the speed and strength of the
ejecting low.

Long term...(wednesday through sunday)
issued at 233 PM CDT sun Aug 2 2015

Northwest flow aloft with a number of weak surface lows and more potent
shortwaves will mean a wet and active extended. On Wednesday a 700
mb low will help thunderstorms develop across the region. By Thursday Lee
side troughing will set up bringing southerly flow and increased
moisture near the surface even as more shortwave energy rides through
the upper ridge. Friday has the least potential for significant
precipitation but by Saturday the pattern will transition back to
southerly surface flow and yet more shortwave energy to help forcing.

Temperatures will be tempered by cloud cover and the northwest flow
aloft. Highs only in the 70s to lower 80s are expected through the


Aviation...(for the 06z tafs through 06z Monday night)
issued at 115 am CDT Monday Aug 3 2015

VFR conditions expected through the next 24 hours. Surface high
pressure continues to build into the region...resulting in clear
skies and light/variable winds. Mainly clear skies expected again on
Monday...with just some fair weather cumulus clouds in the
afternoon. There is another area of smoke from western wildfires
currently over Montana. This smoke may drift over the area on Monday
due to the prevailing northwest flow aloft. At this time...there
does not appear to be any surface visibility obscuration/restriction
associated with this will not mention in the tafs at this time.


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


short term...tmt
long term...wise

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