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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
338 PM CDT Tuesday Jul 28 2015

Short term...(this evening through wednesday)
issued at 337 PM CDT Tuesday Jul 28 2015

Cloud cover with the cold front and veering of surface winds to
southwesterly ahead of the front appear to be putting some clamps on
the Prospect of storm redevelopment before all support moves east of
our area. With boundaries visible on radar and very humid air
lingering...will allow for redevelopment into the start of the
evening...with the threat over before sunset...only in the far
southeast corner of northwest Iowa...or the little Ida Grove to
Storm Lake/kslb stretch.

The rest of the forecast for tonight and Wednesday deals simply with
clear skies and pleasant temperature/humidity conditions. Have
allowed for temperatures tonight to cool a degree or two more than
what we had before for Wednesday morning lows. Good heating will
bring temperatures into the low to middle 80s Wednesday but the air
will be dry. West/northwest winds will reach the breezy category

Long term...(wednesday night through tuesday)
issued at 337 PM CDT Tuesday Jul 28 2015

A northwest flow aloft will prevail over the northern plains for
the foreseeable future providing only skittish chances for thunderstorms and rain and
seasonably mild temperatures. In the intermediate term...we have a
pleasant few days coming up with highs primarily in the 80s and dew
point temperatures that are mild. In fact we have a weak reinforcing
northerly wind moving through late Thursday night and Friday morning
following a middle level short wave...therefore the surface winds will
not become southerly until Saturday. But even on Saturday...dew
point temperatures are only projected to be in the lower to middle 60s.

On Saturday night...the deterministic GFS and European model (ecmwf) have coalesced
around a short wave passage which has been shown by these models off
and on for a few days now. Therefore chance probability of precipitation are still warranted
generally along and east of Interstate 29. Then after that chances
for rain get spotty again with no consensus in solutions. So
certainly high probability of precipitation are not warranted throughout the extended
forecast. As mentioned above...the northwest flow aloft continues
early next week so dew point values should stay in the 60s Sunday
through Tuesday with highs mainly in the 80s.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1226 PM CDT Tuesday Jul 28 2015

Areas of ceilings 1-3k feet from bkx/fsd/sux and east will improve
to VFR from the west 18z-23z. Isolated to scattered thunderstorms and rain in
northwest Iowa east of ksux will move east of the area by 29/00z.
Otherwise VFR through 29/18z. A few surface gusts from the west or
northwest may approach 25 knots over South Dakota through 29/00z.


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


Short term...
long term...mj

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