Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 301058

Area Forecast Discussion
National Weather Service Sioux Falls SD
558 AM CDT TUE AUG 30 2016

.SHORT TERM...(Today and Tonight)
Issued at 253 AM CDT Tue Aug 30 2016

A cold front continues to settle  into the northern portions of the
CWA very early this morning. At this time almost the entire area is
rain free, with earlier convection over our lower IA/NE zones
dissipating. The exception is some scattered thunderstorms brushing
our far southwestern MN zones near Marshall in an area of optimized
low level convergence. The cold front will continue to settle
southward through the morning hours, becoming situated through the
lower Missouri River corridor by late afternoon. With weak forcing,
precipitation trends through the day are rather tricky, with the
main focus for precipitation being low level convergence/confluence
as the front drops southward aided by day time heating. This will
place the better chances for showers/thunderstorms from the central
and eastern Interstate 90 corridor southward into the lower MO River
Valley/northwestern IA during the day. Severe storms are not
expected with limited instability and very weak shear. While
temperatures are also tricky dependent on cloud/precipitation
trends, at this point will go with highs in the upper 70s east of
Interstate 29 to the lower 80s to the west.

The front drops south of our CWA by early this evening, and with
this and loss of day time heating will see any remaining
showers/thunderstorms dissipate across our south. Clouds will be
deceasing overnight, with lowering dew points and cooling
temperatures on a east/northeasterly low level flow. Lows will be in
the mid 50s to around 60.

.LONG TERM...(Wednesday through Monday)
Issued at 253 AM CDT Tue Aug 30 2016

Rather pleasant conditions are expected from Wednesday through
Friday as high pressure over the Great Lakes influences the Tri-
State area. Temperatures will average near to slightly below
seasonal normals.  Dew points will be on the comfortable side, and
winds will remains light through at least Thursday. Breezy winds may
elevate the fire danger west of the Missouri River ever so slightly
on Friday.

The holiday weekend will be considerably more interesting
weatherwise, as southwesterly flow aloft moves into the Central US.
Rain chances will begin to increase later on Saturday as a series of
weak shortwaves lift through the region. Scattered late day
thunderstorms may become more numerous during the evening and
overnight hours. Several clusters of storms may form and lift
northeast through the area into Sunday morning. While the overall
severe weather risk due to the elevated nature of the activity will
be on the lower end, there could be a elevated risk of locally heavy

Considerable uncertainty remains for Sunday and Labor day with
details highly dependent on the mesoscale. Model trends continue to
suggest lingering morning convection, and potential for
destabilization rather quickly in the afternoon on Sunday. However,
far too many uncertainties to get too deterministic on the severe
weather risk.  It is a day to keep a closer eye on given the
increasing shear and instability potential and would not be
surprised to see severe weather convective outlooks introduced for
the region.

Lower confidence on forecast specifics as we move into Monday and
into next week with Labor day convection potential very dependent on
Sunday`s thunderstorms. The broad synoptic pattern continues to
indicate southwesterly flow aloft, typically keeping an elevated
thunderstorm risk into the middle of next week.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 553 AM CDT Tue Aug 30 2016

Seeing showers and isolated thunderstorms develop through portions
of southwestern MN and northwest IA early this morning. Will
continue to see the possibility of scattered thunderstorms, mainly
south of the Interstate 90 corridor, into late this afternoon. Any
of this activity will end by early evening. Winds will be light
through the TAF period.


.FSD Watches/Warnings/Advisories...


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