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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
525 PM CST Monday Nov 30 2015

Short term...(this evening through tuesday)
issued at 315 PM CST Monday Nov 30 2015

Snowfall rates on the downward trend across the eastern half of the
forecast area as upper level wave moves into the region. Main focus
now will be precipitation that sets up associated with the trowal.
Have followed lift in the 295k surface which suggest trowal
developing across central South Dakota over night tonight and then
slowly creeping east towards the South Dakota/Minnesota border
through the day tomorrow. Have raised probability of precipitation into the categorical
range...but precipitation amounts will be significantly less. With
significant downward trend in precipitation rates...could see the
potential for downgrading to an advisory...but have opted to leave
headlines as is for now with coordination. Will see small diurnal
change through the next 36 hours with clouds and precipitation

Long term...(tuesday night through monday)
issued at 315 PM CST Monday Nov 30 2015

Large upper low center wobbles east of the forecast area on
Tuesday evening into Wisconsin by daybreak Wednesday. Band of light
to moderate snowfall on the back side of the low Tuesday evening
will gradually diminish as it also sides east through area...with
the last of snow ending late Tuesday night. Additional snowfall
amounts of up to an inch will be possible. Breezy winds will also
continue overnight...and could allow for some drifting of the
existing snow in open areas.

Behind the exiting low...upper level northwest flow arrives however
the airmass is not expected to be particularly cold. In fact...upper
level ridging building over the High Plains on Wednesday will slide
east through the forecast area through Friday...with southwest flow
developing Saturday. This will allow for seasonally mild low level
temperatures...however with the recent snowpack...daytime readings
will likely be on the cooler side of guidance. Still...high
temperature forecast will be tricky and if greater mixing can
occur...may eventually need to be bumped up. For Wednesday...highs
will reach the upper 20s to lower 30s...and improve a degree or two
each day through the end of the week. Cloud cover will linger across
the eastern half of the forecast area Wednesday morning...then clear
out by early afternoon. Otherwise...mostly clear skies will be the
rule through Friday. Increasing middle level moisture late Friday night
and Saturday will bring in greater cloud cover but it looks to
remain dry.

Upper low forming in The Four Corners region on Saturday...swings
east with the southern stream and will remain largely south of the
forecast area early next week. Temperatures remain similar to
previous the 30s to lower 40s.


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 519 PM CST Monday Nov 30 2015

Periods of light snow will continue across the area through
Tuesday. Conditions will generally remain in the IFR range...with
brief variation in conditions dependent on when snow is falling.
Northwesterly winds will pick up on Tuesday morning and continue
through the day.


Fsd watches/warnings/advisories...
South Dakota...Winter Storm Warning until midnight CST Tuesday night for

Winter Storm Warning until 6 PM CST Tuesday for sdz050-052-053-

Minnesota...Winter Storm Warning until midnight CST Tuesday night for mnz071-

Iowa...Winter Storm Warning until midnight CST Tuesday night for

NE...Winter Storm Warning until midnight CST Tuesday night for nez013-



Short term...
long term...

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