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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
629 am CDT sun Oct 23 2016

issued at 627 am CDT sun Oct 23 2016

See updated aviation discussion below.


Short term...(today through Tuesday afternoon)
issued at 253 am CDT sun Oct 23 2016

The sfc low that shifted across eastern South Dakota has now moved along the
ND/SD/MN border, setting the stage for cooler /but near normal/
air to settle in on north to northwest winds. In fact, a quick
increase in winds has been noted behind this boundary as its
moved east. Accompanying the cooler air during the day today will
be stratus currently across much of northern and central ND. Will
see just how far southwest this cloud shield will be able to go.
The sfc high will shift overhead tonight, allowing temperatures
into the 30s. Upper 20s may still be possible over portions of the
James River Valley. The main concern here is that there may be too
much moisture and possible stratus around, inhibiting the quick
falling of temperatures. This is leading to a lower confidence
fcst at least with temperatures in the short term.

The sfc high will exit across Minnesota on Monday, allowing warm air
advection to return and temps Jump Up about 5 degrees from sunday's
highs. A tightening pressure gradient between the exiting high and
organizing low over Montana/Wyoming Monday afternoon will result in increased
winds around 20kts with higher gusts, especially over central South Dakota.

A chance of wet weather /all in the form of rain/ will return late
Monday night and continue through the day Tuesday, at least for the
eastern half of the forecast area. This will be thanks to the sfc
low shifting into SW South Dakota and western NE.

Will keep the thunderstorm potential out of the area for Thursday
afternoon. While the typically overdone NAM is hinting at the
potential for a few rumbles of thunder, the consensus is to keep the
thunderstorm potential to our south.

Long term...(tuesday evening through saturday)
issued at 253 am CDT sun Oct 23 2016

A mid level shortwave trough will slide across the northern plains
early in the period. By Thursday morning, northwest flow will
develop as a strong ridge builds over the Rocky Mountain region. The
ridge makes its way east, becoming centered over the plains on
Friday before getting pushed east by another shortwave trough set to
track across the region on Saturday.

At the surface, a low pressure system will be over the western High
Plains Tuesday evening, with precipitation likely ongoing across a
good portion of the County Warning Area. This system will push eastward Tuesday
night, with precipitation coming to an end Wednesday morning. Models
begin to diverge toward the end of the period. The European model (ecmwf) brings a
system and chances for precipitation on Saturday, while the GFS
keeps conditions dry. Therefore, will stick with the superblend
solution which leans slightly more toward the European model (ecmwf) and brings some
precipitation to the eastern County Warning Area.

Above normal temperatures will remain through the long term period,
with highs mainly in the mid 50s to mid 60s. Overnight lows will be
in the mid 30s to lower 40s.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 627 am CDT sun Oct 23 2016

An area of stratus currently over North Dakota may make its was
into northern portions of South Dakota this morning. A period of
MVFR cigs is possible at kmbg and kabr. Otherwise, VFR conditions
will prevail today and tonight.


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


Short term...kf
long term...Parkin

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