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Area forecast discussion
National Weather Service Sioux Falls South Dakota
1054 PM CDT Thu Sep 19 2019

Short term...(this evening through Friday night)
issued at 335 PM CDT Thu Sep 19 2019

Southeast winds will continue to draw increasing moisture into the
region tonight. Band of 850 mb warm air advection oriented from
northwest to southeast lifts north through the overnight leading to
a chance of elevated storms. Limited shear and instability should
keep storms below severe limits, but could see some small hail with
stronger updrafts.

Warm air advection lingers in the east on Friday potentially leading
to a stray shower or two across southwest Minnesota through the
morning hours, but the crux of the warm air advection shifts
northeast. Fairly tight gradient across the northern plains will
result in a strong south winds gusting upwards of 30 knots in the
peak heating hours Friday afternoon. Elevated mixed layer looks to
keep the atmosphere largely capped throughout the day on Friday, but
as leading short wave associated with elongated upper level trough
lifts northeast have increasing chances of precipitation.
Precipitable water approaches 1.5" with 30-40 knot low level jet
ushering moisture north from an open Gulf. Potential for heavy
rainfall exists, especially with training of storms. Best chances
of heavy rain look to be focused closer to the mid level wave in
central South Dakota early Saturday morning.

Long term...(saturday through thursday)
issued at 335 PM CDT Thu Sep 19 2019

Dry slot lifts northeast into the forecast area on Saturday bringing
an end to the precipitation from west to east. Cooler air filters
into the region from the northwest with 925-850 mb layer cooling
around 5 c. This will result in high temperatures returning closer
to normal on Sunday.

Warmer air works into the region Monday into Tuesday as upper ridge
develops ahead of trough developing off the West Coast. Models are
in fairly good agreement that wave will head south on the leading
edge of a much stronger jet diving into the Midwest the middle
portion of next week. Still quite a bit of uncertainty on
temperatures as the week progresses, so stuck close to the blend
which is near climatology.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1054 PM CDT Thu Sep 19 2019

Light southeast winds will continue overnight, with increasing
high cloud coverage. Shortly after sunrise Friday, south winds
will increase, with 25 to 30 kt gusts. These last through the
evening hours. Rain and thunderstorms look unlikely for most
locations until Saturday morning.


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


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