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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
606 PM CDT Tuesday Oct 6 2015

Short term...(this evening through Wednesday night)
issued at 256 PM CDT Tuesday Oct 6 2015

Clouds gradually dissipating from northwest to southeast this
afternoon and expect this trend to continue into the evening as
drier air aloft moves in. However a wave in The Rockies will spread
high clouds across the area overnight so any clear skies will be
fairly short lived. A ridge of high pressure will nose in from the
north tonight which will allow winds to remain pretty light...but
radiational cooling will be offset by increasing clouds in most
cases. The coolest lows will likely be in southwest Minnesota where
a few upper 30s will be possible. The remainder of the area should
remain in the middle 40s.

An upper level wave will move across North Dakota Wednesday
afternoon and evening...which will increase lower to middle level
convergence and moisture across the County Warning Area. The better chances should
be over the eastern County Warning Area on Wednesday night as winds turn a bit more
perpendicular to the thermal field and should increase lift a bit.
Instability is marginal so only mentioning isolated thunderstorms
and nothing severe with tall/skinny 500 to 750 j/kg cape. Highs will
be warm...likely upper 60s to middle 70s.

The threat for showers and thunderstorms will shift quickly east on
Wednesday night...with northwest winds beginning to increase towards
Thursday morning. Low temperatures will be very warm ahead of the
incoming cool front...likely in the middle to possibly upper 50s.

Long term...(thursday through tuesday)
issued at 256 PM CDT Tuesday Oct 6 2015

Overnight precipitation should be exiting the southeast corner of our area
by daybreak Thursday...with just a small chance of a lingering
shower southeast of ksux-kspw after 12z. European model (ecmwf) continues to lag the
middle level boundary farther north than GFS/NAM...producing some light
showers from eastern Wyoming/western South Dakota into parts of our forecast area
west of I-29. Gem supports middle level frontal position...but stronger
with low level drying behind departing surface front and thus keeps
precipitation threat west of our forecast area on Thursday. Will maintain
our dry forecast given greater support in that direction...but may
have to watch for spotty sprinkles in the west if European model (ecmwf) pans out. In
either case...should be a fairly mild but breezy day...with highs in
the middle 60s-lower 70s and gusty northwest winds which will subside
quickly toward sunset.

Cooler but still near normal temperatures will make a brief
appearance on Friday before warm and dry west-southwest low level
flow sets up for the weekend and into early next week. Generally
zonal flow aloft will keep the region dry...with daytime highs well
above normal in the 70s to lower 80s. Sunday should be the warmest
day with most areas likely to top 80 in thermal ridge ahead of a
weak wave passing to our north.


Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 605 PM CDT Tuesday Oct 6 2015

VFR conditions expected through the taf period.


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


Short term...08
long term...jh

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