Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 021803

Area Forecast Discussion
National Weather Service Sioux Falls SD
1203 PM CST Fri Dec 2 2016

.SHORT TERM...(Today and Tonight)
Issued at 307 AM CST Fri Dec 2 2016

Spotty, weak radar returns continue to track southeast to through
the region early this morning. Model sounding suggest that the cloud
deck remains just below the level for ice crystal formation, so have
added some patchy freezing drizzle mention in addition along with
the flurries. A few observations have reported non measurable
freezing precipitation this morning, so will continue to keep an eye
on conditions. However, with drier northwest flow arriving at the
surface, and weak ridging rebuilding over the region this morning,
think that this activity will quickly come to an end around sunrise.
With the very light and spotty nature of the freezing drizzle, do
not expect any icing.

Surface ridging builds over the region this afternoon then slides to
the southeast overnight. Clouds will slowly start lifting and
thinning this afternoon, becoming partly cloudy into tonight. Highs
today will be similar to yesterday, in the low 30s north and mid 30s
south. Lows tonight are expected mainly in the low to mid 20s.

.LONG TERM...(Saturday through Thursday)
Issued at 307 AM CST Fri Dec 2 2016

00Z models have kept two distinct systems next week, suggesting much
cooler conditions developing but not a lot of precipitation. On
Saturday through Monday, upper trough digs across the western
portion of the US into the desert southwest and eventually into
Central Texas. This keeps the area under south to southwest flow
resulting in mild temperatures.  The warmest day continues to be on
Monday where highs will at least warm into the 40s.

Early on Tuesday, a strong cold front works through the area.  With
the passage of the front, could see some light precipitation mainly
across southwest Minnesota into northwest Iowa.  As profile cools,
warmest temperatures are contained hear the surface suggesting
smooth transition from rain to snow. If we get enough snow to result
in a snow pack, this could certainly have an effect on temperatures
later in the week.  If not, cold air mass behind the front will
moderate with limited snow pack.  Have blended cons_raw into super
blend to account for cooler temperatures in northwest Iowa into
southwest Minnesota. Cyclonic flow lingers through the remainder of
the work week resulting in below normal temperatures Tuesday through


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1158 AM CST Fri Dec 2 2016

The 18Z TAFs reflect primarily lower end VFR to MVFR conditions
through the evening hours. However later, as high pressure slides
off to the east, surface and low level winds will become southerly
late tonight. There is currently clear or mostly clear skies in
central and southern Nebraska. Therefore when the winds become
southerly, it is likely only a matter of time before the stratus
advects to the north. Reflected this in the 18Z TAF sites by
scouring out the lower deck from west to east late tonight and
Saturday morning. That said, a higher deck of clouds firmly in the
VFR category will then move in when the stratus clears out.




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