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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
534 PM CST Wednesday Nov 26 2014

Update...
the aviation discussion has been updated for the 00z tafs.

&&
Previous discussion...
short term...tonight through Thursday
high pressure continues to sag south...now centered over southern
Manitoba. Models show the center of the high over the South Dakota/ND/MN
border by early Thursday morning. Light winds...clear skies...and
fresh snow will make for ideal radiational cooling conditions over
the eastern half of the County Warning Area. Expect temperatures to drop into the low
single digits or teens below zero by early Thursday morning. Further
west however...cloud cover and less snowfall should keep lows in
the single digits above zero.

Cold temperatures persist into Thanksgiving day across the
northeastern 2/3 of the County Warning Area. Return flow winds and warm air
advection will keep the southwest County Warning Area will be warmer. In
fact...the temperature gradient will range from the single digits
across the northeast County Warning Area to near 35 degrees across the southwest.
Isentropic lift combined with weak upper level forcing will result
in light snowfall...spreading from west to east across the
northern County Warning Area. Due to the strong push of middle level warm air
Thursday afternoon there could be a brief window of mixed
precipitation. BUFKIT soundings...sref probabilities and model
dominant ptype forecasts all supports this occurrence. Therefore went
ahead and threw the wintry mix into the forecast during the late
afternoon hours...a very brief window. The best chance of this
occurrence will be over the northwest County Warning Area...and no ice
accumulation is anticipated at this time.

With continued warm air advection through the night...temperatures
will remain pretty steady...or even rising into Friday morning.

Long term...Friday through Wednesday
the models show pretty good agreement in the long term with the
overall weather pattern with some slight differences in timing and
locations of surface features. The long term begins with our
region in the warm sector/Pacific air dominating the region with a
surface low pressure area out West Riding along a southward moving
Arctic boundary for Friday night and Saturday. Thus...expect
Friday and Saturday to be dry with temperatures near to above
normal across the County Warning Area. The snow cover and winds will have an
effect on the temperatures for both days. We may also be looking
at some late night/early morning fog with the snow melt occurring
and higher dew points across the region. Otherwise...an Arctic
front will push south across the region probably Saturday afternoon
and evening with strong north winds in behind it. The Arctic air
and cold blustery north winds will continue into Sunday with much
below normal temperatures for Sunday. Highs Sunday will be mainly
in the upper single digits to upper teens across the County Warning Area. The
surface high pressure area will then settle over the region for
Sunday night/Monday morning. With the clear skies and light winds
for this time...lows will be mainly below zero across the County Warning Area. The
surface high pressure area will push east for Monday and Tuesday
with warmer air again returning. Temperatures will get back close
to normal or slightly above by Tuesday. Wednesday will be slightly
cooler across the region. Otherwise...the entire long term is expected
to be mainly dry across the County Warning Area.



&&

Aviation...
00z tafs for the kabr...Katy...kpir and kmbg terminals

A mix of MVFR/VFR ceilings will dominate the kpir/kmbg terminals while
the Katy/kabr terminals should experience VFR conditions through
tonight.



&&

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

$$
Update...tdk
short term...serr
long term...mohr
aviation...tdk

Weather.Gov/Aberdeen

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