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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
643 PM CDT Monday Aug 31 2015

Short term...(this evening through tuesday)
issued at 337 PM CDT Monday Aug 31 2015

Upper level wave and jet maximum moving quickly northeast into southern
Canada...and will gradually lose influence over the area tonight. An
incoming boundary has worked into the far western County Warning Area but this
boundary will weaken overnight as the wave moves farther and farther
northeast. This should allow the front to stall out and could serve
as a focus for some fog development. For now will not go with this
as the middle and high cloud cover should keep temperatures from
radiating too far down. Will include some patchy fog over far
southeast South Dakota into northwest Iowa where skies will be clear
the longest and the ground is the wettest. Will maintain a small
chance for showers and thunderstorms in south central South Dakota
as the front moves in and weakens and middle level moisture increases
enough to potentially support a little activity. Overall lows should
mainly be in the middle 60s.

Another warm and humid day Tuesday as southerly flow becomes
reestablished across the area. Highs mainly in the middle to upper 80s.
While thunderstorm activity is unlikely will need to keep an eye on
southwest Minnesota as the warm front lifts north and the cap
decreases through the afternoon.

Long term...(tuesday night through monday)
issued at 337 PM CDT Monday Aug 31 2015

Relatively warm...muggy and breezy week expected across the area as
upper ridge builds into the area. With climatological highs near 80
and lows in the middle 50s...expect temperatures to be around 10
degrees above normal. Appears to be some skittish chances of
precipitation across portions of the forecast area mainly at night
across the east.

Models start to diverge on Friday as the European model (ecmwf) shows a strong
shortwave focused on moving across the forecast area...while the GFS
keeps a short wave train across central South Dakota and areas to
the west. Weekend appears to be more active with additional waves
tracking across the area. Models have suggested that the cold front
initially expected to move through on Sunday has slowed
have raised forecast highs with coordination. Also raised forecast
lows Sunday night in the east...but with the GFS bringing the front
through on Sunday night was hesitant to make changes to Monday.
European model (ecmwf) weakens the front and keeps it bottled to the west...thus
suggesting a continuation of the warm mild temperatures at least
through Labor Day.


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 639 PM CDT Monday Aug 31 2015

The 00z tafs reflect some MVFR smoke at khon. The wind shift to
the north in that area has allowed some mixing of the smoke aloft
to the surface. Not sure how long that will last...but will
include it for now as the webcam at Huron South Dakota is quite hazy.
Otherwise it is a matter of just watching low stratus or fog
again late tonight at kfsd and ksux. If we can get some middle clouds
to come over at those sites late tonight...that could help
alleviate the fog situation.


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


Short term...08
long term...

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