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fxus63 kfsd 261130 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
530 am CST sun Feb 26 2017

Short term...(today and tonight)
issued at 344 am CST sun Feb 26 2017

Should be a nice late winter day across the area. Mid clouds across
the area early this morning expected to decrease by shortly after
sunrise, leaving plenty of sunshine and modest westerly winds. Weak
cool front drops to near Highway 14 corridor toward sunset, and
could see a very late day/evening increase in mid clouds across the
northern portions of the cwa, but these should retreat overnight as
the boundary lifts back to the north.

Expect temperatures today to be 3-5 degrees warmer than yesterday on
average. Southern areas will remain coolest over the snow cover, but
should climb a few degrees above freezing to begin the next round of
snowmelt. Light winds and mostly clear skies over the deeper snow
should provide for good optimal radiative cooling, and could see
some light fog develop as temperatures quickly drop back into the
lower 20s and teens this evening and overnight.

Long term...(monday through saturday)
issued at 344 am CST sun Feb 26 2017

Monday appears to be above normal with warm air advection regime and
flow out of the southwest, but the lingering snowpack will limit the
warming potential. Have lowered forecast highs a bit across
northwest Iowa where the heaviest snow fell.

Monday night is tricky as warm air advection ahead of a series of
weak waves results in a developing warm nose around 925 hpa and
potentially some light precip. The dry forecast solution (gfs) for
the past several runs is now the wettest. Sref plumes suggest the
potential for saturation issues aloft, so favored the other drier
solutions. Have raised temperatures and dew points which mainly kept
precip across northwest Iowa as drizzle. Have a mention of freezing
drizzle on the far western fringes of the pops, but am not sure the
saturation will be deep enough there to result in accumulations.
Have also added the mention of fog with the low level saturation.

Once the series of waves move through, there is a cooling trend
midweek with a series of waves dropping through in northwest flow.
The wave on Thursday appears to be the strongest, potentially
leading to some light snow across southwest Minnesota. Have nudged
pops up for this feature. There is a second wave coming through on
Friday, but appears to be very moisture starved.

Nice warm up is expected on Saturday, with the potential for
additional warming on Sunday if the GFS is correct. The European model (ecmwf) has a
cold front swinging through on Saturday evening, while the GFS is
nearly 24 hours slower. Have raised forecast highs on Saturday
closer to bcconsmos and bcconsall, but did not modify sunday's highs
with uncertainty in the timing of the front.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 530 am CST sun Feb 26 2017

VFR conditions expected throughout the day. Melting snow may add
enough moisture to near-surface layer to allow fog to develop as
temperatures cool this evening, with patchy MVFR-IFR visibility


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

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