Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 302133

Area Forecast Discussion
National Weather Service Sioux Falls SD
333 PM CST Wed Nov 30 2016

.SHORT TERM...(This evening through Thursday)
Issued at 333 PM CST Wed Nov 30 2016

Upper level support and low to mid level warm/moist advection will
gradually weaken into the overnight hours. This should allow
snowfall rates, which were already fairly minimal, to diminish from
southwest to northeast. Low and mid level moisture will linger so,
while it is not in the forecast, there is a chance that flurries
could linger into tomorrow. With the clouds hanging tough and winds
staying up a bit went for a smaller diurnal range and much closer to
the raw model output. Same for Thursday, only expect temperatures to
rise 3-6 degrees under cloudy skies. Added a small chance for late
afternoon light snow around the mid James Valley as some residual
upper level forcing will try to work with a little lower and mid
level moisture. Overall the low to mid level moisture are a bit
disjointed and the upper level forcing is not exactly in the area
with the better saturation potential so that is the reason for the
small chance.

.LONG TERM...(Thursday night through Wednesday)
Issued at 333 PM CST Wed Nov 30 2016

If light snow mentioned above does materialize in the James Valley
Thursday afternoon, we could still see a few flurries linger into
Thursday evening as last bit of energy rotates around the departing
low. However, uncertain that this will occur, so opting to leave
mention out for now.

Upper pattern gradually transitions to a weak ridge over the
Northern Plains for Friday and Saturday, which should allow for some
modest warming by Saturday as we see increasing amounts of sunshine
across the region. Weak northern stream trough swings across the
northern Plains during the latter half of the weekend. Current
phasing of the trough with moisture return from the south appears to
focus light precip chances from our far east, into Minnesota/Iowa
Saturday night. Mild weather continues behind this trough with above
normal/above freezing temps expected for highs through Monday.

A weakening trough swings northeast through the plains Monday, and
this could to some light precipitation later Monday into Monday
night. With the relatively mild airmass in place, should see any
precipitation begin as light rain Monday afternoon. Colder air will
gradually push in behind this trough, though timing of this cooldown
varies from model to model, so timing of rain/snow transition could
be adjusted in the coming days.

Models pointing to a stronger system moving through the region
toward the middle of next week. Again, models showing a lack of
consistency with this system at this range, so did not make any
adjustments to the broad model consensus at this time. Somewhat
better agreement on a vigorous cold push behind this system, which
will bring in a period of sharply colder air by the end of this
forecast period.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1107 AM CST Wed Nov 30 2016

Widespread MVFR and IFR conditions in stratus and light snow. The
light snow will gradually diminish from west to east through the
afternoon and evening, but the IFR stratus will remain in most
locations through the end of the TAF period.




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