Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 242311

Area Forecast Discussion
National Weather Service Sioux Falls SD
611 PM CDT SUN JUL 24 2016

.SHORT TERM...(This evening through Monday)
Issued at 310 PM CDT Sun Jul 24 2016

Watching a subtle shortwave over southwest South Dakota push east
through the region this afternoon and evening.  200 j/kg of
instability elevated around 600 mb continues to produce scattered
diurnally induced light rain showers ahead of the wave.  These
showers will track east over the next few hours but should dissipate
by sunset as we lose the heat of the day. Lightning has been very
isolated and continues to show a downward trend as the shower push
east. With a significant dry layer in the low/mid levels, much of
the rain will evaporate before reaching the surface. Skies will also
clear this evening and remain mostly clear into Monday. With surface
high pressure building overhead, drier air, light winds, and
dewpoints return tonight. Lows will be a few degrees cooler in the
upper 50s and lower 60s.

Surface high pressure skirts off to the southeast while an upper
level ridge builds over the northern plains on Monday.  Return flow
will allow temperatures to warm again, but not the the extreme
levels of last week. With lower dewpoints, excessive heat will not
be a concern. Highs will be in the mid 80s to lower 90s.

.LONG TERM...(Monday night through Sunday)
Issued at 310 PM CDT Sun Jul 24 2016

Stable and dry air across the area will very slowly give way to
increasing instability and moisture Monday night and Tuesday as
warming aloft develops, producing an eventual favorable environment
for decent shower and thunderstorm coverage. Still Expect this
coverage to peak Tuesday night over the area, with coverage
decreasing slowly to the southeast Wednesday. Despite the warming,
daytime temperatures will show a cooling trend under minimal low
level warming and somewhat limited daytime heating. Highs in the 80s
to low 90s Tuesday will cool to the upper 70s to mid 80s for

The heating on Tuesday and a half decent mid level westerly flow
could help and isolated storm or two to reach severe limits late
Tuesday as per the early morning SPC day 3 outlook. However, shear
appears to be otherwise limited and CAPE will probably increase
only to the 2000 J/kg or so range. There appears to be a chance of
some decent rainfall amounts by Tuesday night, although parameters
appear to lack the beef for excessive short term rainfall.

Thursday and Friday appear to continue some threat of showers and
storms, as short waves pass and force the upper flow to become a
bit more northwesterly. Temperatures will remain kind of cool. By
the weekend, there appears to be enough ridging behind these waves
for some dry and pleasant weather, but will for now keep the
extended guidance suggestion of some rain lingering east Saturday.

Medium range models suggest a warming again after the forecast
period for the first week of August, although for now the warming
does not appear to threaten the degree of excessive heat and
humidity we just got done with.


.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 611 PM CDT Sun Jul 24 2016

Mid level cloud deck lingering over northwest Iowa at the start of
the period will diminish through the early evening, with mostly
clear skies then expected through the remainder of the TAF period.


.FSD Watches/Warnings/Advisories...


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