Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 250352

Area Forecast Discussion
National Weather Service Sioux Falls SD
1052 PM CDT WED AUG 24 2016

.SHORT TERM...(This evening through Thursday)
Issued at 233 PM CDT Wed Aug 24 2016

Weather will remain on the quiet and cool side through Thursday,
with weak surface ridge passing through the area tonight, followed
by a secondary cold front on Thursday. Mid level frontogenesis over
the area resulting in fairly extensive mid-upper level cloud cover
this afternoon, but expect this to diminish later tonight, allowing
temperatures to drop into the lower-mid 50s by daybreak Thursday.

Moisture limited across the area Thursday, though could see some
post-frontal cumulus in parts of southwest Minnesota/east-central
South Dakota. Highs Thursday will be the coolest of this forecast
period, ranging from around 70 in the areas where cumulus is more
favored, to mid-upper 70s from the Missouri Valley into northwest

.LONG TERM...(Thursday night through Wednesday)
Issued at 233 PM CDT Wed Aug 24 2016

Thursday night looks to be a relatively quiet night with surface
high pressure over the eastern two thirds of the forecast area.  As
the system shifts east throughout the night, there could be some
high clouds working into central South Dakota. These clouds may
hamper what otherwise would be good radiative conditions.

Return flow increases on Friday ahead of a shortwave approaching
from the southwest.  Moisture appears to be fairly limited, despite
relatively good dynamics.  Wave moves into the right rear quadrant
of upper jet that is situated across the eastern half of the
forecast area Friday night. Crux of the wave is focused across
central South Dakota, gradually spreading northeast across the
forecast area. Timing is still a little uncertain, but appears to be
a little slower than suggested in the previous forecast.  Overall,
have the highest pops focused east of I-29 after midnight early
Saturday morning.  Upper level trough is relatively slow to shift
east through the day on Saturday, and could see some additional
showers and thunderstorms throughout the day.

Thereafter, flow becomes fairly zonal, but an intensifying shortwave
lifts from the central plains north and east affecting portions of
northwest Iowa into far southwest Minnesota. Best chances of
precipitation with this wave appears to be Monday night into

As this wave shifts east, upper level ridge is expected to build
into the upper midwest leading to dry but warming conditions in the
middle to late portions of next week.


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1049 PM CDT Wed Aug 24 2016

VFR is expected for the remainder of tonight and Thursday with one
thing to watch for. There are some indications that patchy fog may
setup just before sunrise Thursday morning in northwest Iowa.
Indeed, current surface dew point depressions are pretty small at
this time. For now, left lowered visibilities out of the KSUX TAF
site as various guidance values are showing patchy fog to develop
to the east of Sioux City. But this will be monitored.


.FSD Watches/Warnings/Advisories...


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