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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
520 am CST Friday Feb 12 2016

Short term...(today and tonight)
issued at 330 am CST Friday Feb 12 2016

Cold and dry Arctic air will erode cloud cover from northeast to
southwest through the morning...leading to a mostly sunny to partly
cloudy day for most. Cloud cover may hang up a bit in south central
South Dakota and with an approaching wave tonight middle and high clouds may
start to push back into south central South Dakota late this afternoon. Some
areas are seeing the warmest temperatures of the day right
now...with steady or falling temperatures through the day. Highs
mainly single digits to teens...with a few 20s in south central South Dakota
where cloud cover could hold temperatures up a bit.

By tonight the combination of wind and cold temperatures will bring
wind chill values down to 20 below zero or colder...especially over
southwest Minnesota into northwest Iowa. Will have a Wind Chill
Advisory for those locations although the wind will diminish through
the night. Lows will range from 10 below to 15 below across
southwest Minnesota and northwest Iowa to 5 to 10 above in south
central South Dakota.

Long term...(saturday through thursday)
issued at 330 am CST Friday Feb 12 2016

On Saturday the surface ridge over our area slides off to
the east...while midlevel warm air advection/isentropic lift begins
to overspread the area from the west. This will bring increasing
light snow chances through the southwestern half of our County Warning Area during
the day. Farther to the east...low level dry air will linger so not
expecting much through those areas. Will have increasing southerly
winds during the afternoon in a tightening gradient as a surface
trough slides into the western High Plains. Very cold air will
remain entrenched over much of our County Warning Area on Saturday with highs in the
teens...though warmer air will begin to advect into our south
central South Dakota zones where highs will top out in the middle and
upper 20s.

On Saturday night a shortwave drops out of the northern rockies into
the northern plains overnight...with models continuing to have
better agreement on the track of the system. This will bring better
snow chances to our northern and eastern County Warning Area where lift will be
optimized. Snow ratios will be pretty high...running from around
15:1 to 20:1...and there is the potential for 4 or 5 inches of
accumulation through the Highway 14 corridor and much of our
southwestern Minnesota zones by Sunday morning. Southerly winds will
continue to increase on Saturday night...gusting to around 30 miles per hour at most likely looking at areas of blowing snow.
Temperatures on Saturday night will not drop much from daytime
highs...mostly teens to lower 20s.

Saturday will be the coldest day for a while as warmer air returns
to the region for the beginning of the week. Models differing on the
degree of warming...but all trend generally to highs for Sunday and
Monday in the 20s and 30s...with some 40s through the upper Missouri
River corridor. It looks to be dry for the start of the week.
Another shortwave drops into the region for midweek...resulting in
slight cooling for Tuesday and Wednesday...then more significant
warming may be realized toward the end of the week as an upper level
ridge builds across the region.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 519 am CST Friday Feb 12 2016

Patchy MVFR ceilings will be possible through middle to late
morning...then Arctic air will bring clearing from the northeast.
After late morning VFR conditions are expected.


Fsd watches/warnings/advisories...
South Dakota...none.
Minnesota...Wind Chill Advisory from 7 PM this evening to 9 am CST Saturday
for mnz080-081-089-090.

Iowa...Wind Chill Advisory from 7 PM this evening to 9 am CST Saturday
for iaz002-003-013-014-021-022.



Short term...08

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