Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 252247

Area Forecast Discussion
National Weather Service Sioux Falls SD
547 PM CDT SAT JUN 25 2016

.SHORT TERM...(This evening through Sunday)
Issued at 228 PM CDT Sat Jun 25 2016

Cold front quickly moving west to east across the area and had
cleared Interstate 29 right around 18z. Some near to slightly
elevated post frontal convection developed in northeast nebraska
and will work northeast through the afternoon. The threat for
severe storms will wane quickly as the front should be east of the
cwa by about 23z or so. Between now and about 0z there may be some
isolated severe storms in northwest Iowa and parts of southwest
Minnesota but all there is to work with is instability, in the
form of CAPE values around 2500 J/kg. Shear is virtually non
existent with some marginal amounts in the surface to 2 km layer,
but above that support weakens. That is why we likely will
continue to see storms reach to near or a little above severe, but
then diminish shortly after. Behind the incoming front is very dry
air, with dew points into the 20s and 30s in western South Dakota.
This area will not see humidity that low, but the drier air will
see dew points fall about 15 to 20 degrees below the highest
readings today, which will make for a very nice Sunday. Lows
tonight will be in the upper 50s while highs on Sunday will be
from the mid 80s to Lower 90s. A bit hot, but not humid and sunny.
Windy along and north of Interstate 90.

.LONG TERM...(Sunday night through Saturday)
Issued at 228 PM CDT Sat Jun 25 2016

Fairly quiet weather expected through the first half of the week as
a slow transition to northwesterly flow aloft begins. Weak
isentropic lift may be sufficient for a few elevated storms near the
Missouri River valley Monday afternoon and again around daybreak
Tuesday, however most areas will remain dry into early Wednesday.
Temperatures Monday and Tuesday will remain near to slightly below
seasonal normals, something that`s happened only a handful of days
in June.

Northwest flow will bring a slightly more substancial wave through
the region on Wednesday. Typical track issues with northwest flow
have this wave tracking from western SD/NE in one solution to over
eastern SD/NE in another. The preference falls in between, which
continues to place the highest PoPs near the Missouri and James
River valleys late Tuesday night into Wednesday. Cloud cover could
play a major role in temperatures on Wednesday, with slightly below
normal temperatures currently forecast.

Pesky northwesterly flow will persist through next weekend. Models
will continue to show considerable variability in their individual
solns. It`s not inconceivable to have low end PoPs nearly every day,
with a diurnal preference in storm type. Temperatures will climb
slightly above seasonal normals by this weekend, with more favorable
humidity levels. With the prevailing northwesterly flow continuing
through the 4th of July week, there doesn`t appear to be any major
heat waves on the way.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 541 PM CDT Sat Jun 25 2016

Showers and isolated thunderstorms will continue to push to the
east, exiting northwestern Iowa by 02z. Otherwise, skies will
clear with northwesterly winds dropping off overnight as VFR
conditions rule through the remainder of the TAF period.


.FSD Watches/Warnings/Advisories...


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