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fxus63 kfsd 270440 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
1040 PM CST sun Feb 26 2017

Short term...(this evening through monday)
issued at 257 PM CST sun Feb 26 2017

A very nice Sunday across the region thanks in part to sunny skies
and light warm advection aloft. Temperatures have risen above
freezing in most areas, with the warmest readings again in the
snow free portions of the County Warning Area.

For tonight, winds are expected to remain southerly. This should
result in a fairly mild overnight, with lows holding either side of
20 degrees. Couldn't rule out a bit of light fog, but boundary layer
winds may be just mixy enough to preclude any widespread dense fog.

A frontal boundary remains north of the County Warning Area on Monday, and with low
level temperatures again climbing significantly over today,
temperatures with the slightly stronger southerly flow should bounce
into the 40s. The Fly in the ointment to any strong warming will
likely be the increase in mid-level clouds in the afternoon ahead of
a broad wave of energy moving into the plains. Any stratus should
hold off until Monday night.

Long term...(monday night through sunday)
issued at 257 PM CST sun Feb 26 2017

Monday night into Tuesday remains a tricky forecast, in the warm air
advection regime ahead of approaching shortwaves. With southerly
flow tapping into milder temperatures and increased low level
moisture. With a substantial warm and dry layer aloft to overcome,
precipitation will likely be limited to primarily drizzle or
freezing drizzle Monday night into Tuesday morning, with perhaps a
few flurries in central South Dakota. Areas of fog will also develop across
the region. Temperatures will be tricky, with cloudy skies and
warming temperatures aloft, so raised lows slightly across northwest
Iowa and adjusted the hourlies to fall slower through the night.
Precipitation exits the area by midday Tuesday. Highs on Tuesday
will warm back into the upper 30s to lower 40s.

Northwest upper level flow on Wednesday through Friday will keep
temperatures near seasonal values, while directing a pair of waves
through the region. The first of these arrives late Wednesday night
into Thursday, with the arrival of a cold front. Temperatures will
be cold enough to support a chance of some light snow with this fast-
moving system. The second wave dives through the northern plains on
Friday, but moisture will be quite limited. Will leave much of the
forecast area dry.

It still looks like the upper pattern transitions to more of a zonal
flow headed into the weekend. Expect a nice warming trend with dry
weather during this period. Nudged highs both days slightly warmer
towards the bcconsmos numbers. Highs should recover into the upper
40s and 50s.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1037 PM CST sun Feb 26 2017

VFR conditions will dominate through the taf period. With
relatively light winds and recent snow melt, there will be a
possibility of patchy fog through northwestern Iowa overnight,
though confidence is too low to include in the ksux taf.


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

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