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Area forecast discussion 
National Weather Service Aberdeen South Dakota
322 PM CST Monday Dec 22 2014

Short term...tonight through Wednesday night
main challenge in the short term is snow amounts tonight and
Tuesday with the storm system currently over the region. The
center of the surface low currently extends from eastern South
Dakota to northern Missouri. Warmer air being pulled up on the
east side of the low has kept the precipitation there in liquid
form...while snow is occurring over the west where somewhat
cooler air is now moving in. The models are in pretty good
agreement that most of the snowfall will occur tonight into
Tuesday morning across the western half of the County Warning Area...where amounts
of 3 to 5 inches look possible. Due to the lingering warm air over
the will take longer for the snow to amounts
of 1 to 2 inches look more likely. Will also see the winds
increase across the west as a decent pressure gradient sets
up...with 20 to 30 miles per hour winds likely to aid in some blowing and
drifting of the snow and possibly reducing visibilities.
Therefore...will stick with a Winter Weather Advisory for all the
counties west of the James River Valley. The winds will not be as
strong across the east...and by the time they do pick up a
little...the snow will be coming to an end.

The remainder of the near term looks dry as high pressure moves in
behind the exiting storm system. Temperatures will be fairly mild
as there will be no real significant cold air with or behind this
storm system. Highs will be in the upper 20s to middle 30s both
Tuesday and Wednesday...with overnight lows in the teens to middle

Long term...Thursday through Monday
main issue in the extended period is the storm system moving
across the plains Thursday and Friday. There is actually pretty
decent agreement amongst the models for the time being. The low is
fairly progressive as it tracks easterly across Kansas/Nebraska
into Iowa. There will also be a cold high pressure system building
south into the northern rockies/High Plains. This will create a
baroclinic zone right across South Dakota. Models are showing a
few inches of snow across the region as the low tracks east. At
this point it does not appear to be a major snow producer due to
the rather quick movement of the low. Although...given the
pressure gradient across the area it appears winds will be fairly
strong which will cause issues with blowing snow. Still plenty of
time for this storm to change course but as of right now this is
what models are showing...and with pretty good agreement
surprisingly. Have increased probability of precipitation a bit for this time frame.

Otherwise...after this storm system exits it looks like we will
head into some colder temperatures...with highs in the teens for
most areas by this weekend. Overnight lows are forecast in the
single digits...but would not be surprised if these lower some
over the coming days. Mex guidance hints at colder temperatures.


18z tafs for the kabr...Katy...kpir and kmbg terminals

-sn will affect kabr and kmbg through the taf period...with -rasn
at Katy and kpir. Although...the latter two terminals are expected
to switch to -sn by later today. Ceilings vary at taf issuance ranging
from MVFR to as low as 400 feet. Expect this to continue...with the
lowest ceilings at kabr and Katy through the day and night. Although
kmbg and kpir should see falling ceilings as snow intensifies through
the day and night. Visibility in kabr and Katy has risen above 1sm as
fog/br has lifted. Through the day and night...expect visibility to lower
as -sn/snow develops and intensifies. Kmbg and kpir expected to see
the lowest ceilings by this evening and overnight as snow and blsn
develop with strong northwest winds. Visibility may fall to around
1/2sm in snow and blsn.


Abr watches/warnings/advisories...
South Dakota...Winter Weather Advisory until 6 PM CST /5 PM MST/ Tuesday for

Dense fog advisory until 6 PM CST this evening for day-Marshall-


Short term...Parkin
long term...tmt


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