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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
251 PM CDT Tuesday Jul 29 2014

Short term...(this evening through wednesday)
issued at 245 PM CDT Tuesday Jul 29 2014

Diurnally driven cumulus will dissipate with sunset...setting up another
mainly clear...calm and cool night. Will continue to go with lows on
the cool side of guidance...generally between 50 and 55. Will have a
weak area of low pressure that will drop south across central South
Dakota tonight into tomorrow. Weak thetae advection ahead of this
system could bring an increase of middle level clouds to areas west of
the James River late tonight...with this area also seeing partly
cloudy skies tomorrow. Some of the hi res models along with the NAM
and sref show some light quantitative precipitation forecast west of the James tomorrow with this
feature. However soundings only show thin and minimal cape...with a
cap above 600 mb. Thus does not look favorable for much more than
maybe a few will keep the forecast dry.
Elsewhere...with a slightly drier boundary layer depicted in model
soundings...cumulus field should be less extensive than today.

850 mb temperatures warm about a 1c across the board
tomorrow...meaning we will probably end up around 2 to maybe 3
degrees warmer than today...generally between 77 and 82. And with
light winds and low dewpoints ... be another pleasant day for
outdoor activities.

Long term...(wednesday night through tuesday)
issued at 245 PM CDT Tuesday Jul 29 2014

A stretch of primarily dry weather will continue into the upcoming temperatures begin a slow upward trend. For Wednesday
night/Thursday morning...have added a slight chance pop over the far
west. Guidance continues to show weak shortwave over Saskatchewan
dropping south by Wednesday evening. Despite rather poor
moisture...there may be just enough isentropic lift to generate a few
showers overnight...but quantitative precipitation forecast amounts will be light.

The persistent northerly flow will continue to bring several waves
of energy southward through Friday all of which could produce very
light echoes. Generally though...confidence on coverage and
placement too low to include any probability of precipitation at this time. Temperatures will begin
to climb...albeit slowly...and we'll still have average temperatures
a degree or two short of normals.

Heading into the weekend...the upper level pattern will begin to
break down on Saturday with middle-level heights slowly beginning to
rise over the central Continental U.S.. the weekend should remain dry as a
surface boundary forms north of the County Warning Area. Rain chances will begin to
increase early next week with GFS/European model (ecmwf) differing slightly on the
location of the elevated boundary. Several disorganized waves of
energy are expected to advect into the northern plains...and depending
on their track...we could have our first shot at widespread rains in
some time.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1217 PM CDT Tuesday Jul 29 2014

VFR conditions will prevail through the period. Just some diurnal
scattered to broken cumulus based around 5000 to 6000 feet through this
afternoon...with some lingering middle level clouds possible overnight
out west. Could also see some patchy areas of shallow fog for a brief
period Wednesday morning...similar to what we saw this morning.


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


Short term...chenard
long term...dux

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