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fxus63 kfsd 101616 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
1016 am CST Tue Dec 10 2019

Short term...(today and tonight)
issued at 316 am CST Tue Dec 10 2019

Light snow and flurries continue to work across the forecast area
this morning. Gusty northwest winds have also spread eastward and
we are observing a few 30 knot gusts. These gusty winds will
begin to subside through daybreak as the surface pressure gradient

Temperatures which warmed through the night in response to passing
mid-lvl energy, will begin to drop as cold advection rushes
southward this morning. Low temperatures may actually bottom out
during the late morning hours before rising slightly this afternoon.
However a very cold day is anticipated in many locations with highs
only in the single digits.

Tonight: models again showing a 150+ knot upper jet forming across
the Western Plains later this afternoon. Low-lvl warm advection
begins to increase by this evening, which should begin to produce a
narrow corridor of light snow through central and eastern South
Dakota by late evening. Model guidance has trended northward
slightly this morning, creating the potential for a dusting to inch
of snow in some locations along and south of I-90 into the early
morning hours of Wednesday.

Long term...(wednesday through monday)
issued at 316 am CST Tue Dec 10 2019

Wednesday: overnight temperatures will be buoyed by cloud cover
for much of the night, but once again a strong surge of cold air
arrives by daybreak Wednesday. Clearing skies and light winds
could lead to significant radiational cooling along the northern
edges of the County Warning Area with lows approaching -10 in some locations.
Another non-Standard diurnal curve is expected through the day.

Wednesday night-thursday: a progressive mid-lvl vorticity maxima
moves through the central and northern plains into Thursday
morning. Based on the track of the wave, the highest chances for
warm advection snows focus just north and east of the County Warning Area.
However, we will need to watch for the potential for a brief
period of freezing drizzle during the overnight hours. Temperatures
though will rise through the night, especially south of I-90.
After a brief dip in temperatures Thursday morning, we'll only see
a light rise back into the teens to lower 20s in the afternoon.

Friday-monday: a more progressive and slightly warmer pattern
briefly develops by Friday, with warming low-lvl temperatures
pushing highs into the 30s and even 40s Friday afternoon. Increasing
chances for light snow arrive Friday night into Saturday morning.
Temperatures cool significantly again next weekend as high
pressure sinks southward. Low temperatures will again fall below
zero in some locations, with highs well below normal.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1014 am CST Tue Dec 10 2019

Patchy MVFR clouds will bepossible this afternoon but persistent
ceilings are not expected. A fast moving system will bring a short
lived band of snow to the area overnight. The better chances will
be from roughly 2z through 10z. More than likely the band of snow
will be south of khon and just a bit north of ksux but clip kfsd
from about 4z to 7z. MVFR conditions are likely within the band of
snow and very brief IFR conditions possible.


Fsd watches/warnings/advisories...
South Dakota...none.

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