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fxus63 kfsd 272021 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
321 PM CDT Thu Jul 27 2017

Short term...(this evening through friday)
issued at 321 PM CDT Thu Jul 27 2017

Dry conditions with seasonable temperatures are the main story for
the end of the week. Surface high pressure centered over NE/Minnesota
border, will continue to prevail across the area, at least through
Friday night. A weak shortwave currently located over eastern
Wyoming/western South Dakota will make its way eastward, gradually shifting winds
to a more southerly component, mainly west of the James River.
Precipitation is not expected in the near-term; but southerly
flow/warm advection will begin to spread some mid clouds into the
area in the nighttime from west to east. Tonight will be mild but
seasonal, with lows in the upper 50s and 60s. As the main surface
high moves eastward into the Great Lakes, east-southeast wind flow
will prevail on Friday for most of the area, bringing another dry
and pleasant day with daytime dewpoints only in the lower 60s. Highs
on Friday will be ranging in the 80s.

Long term...(friday night through thursday)
issued at 321 PM CDT Thu Jul 27 2017

Relatively quiet period through the extended with upper level ridge
across the southern half of the US retrograding back the west and
expanding northward to cover much of the western half of the
country. This will result in weak northwest flow aloft. This should
promote generally dry and seasonal temperatures, but could see a few
sporadic chances for precipitation.

Blend produced pops Friday evening across central South Dakota
associated with ribbon of 850 warm air advection/Theta-E advection.
Instability/low level moisture remains extremely limited and have
reduced pops to less than 15 percent.

On Sunday, there may be a few elevated storms associated with the
low level jet, but convergence is very weak.

Should see temperatures warm through the first half of the week next
week ahead of an approaching cold front. With the passage of the
front, could see some scattered storms especially across the eastern
half of the forecast area. This looks to be the best chance for
widespread precipitation.

Heat quickly builds into the region behind the front from the west,
resulting in seasonal if not above normal temperatures by weeks end.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 106 PM CDT Thu Jul 27 2017

VFR conditions expected through the period. Low VFR ceilings due
to scattered cu expected to remain through early evening.


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

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