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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
1232 PM CDT Thursday Jul 31 2014

Short term...(today and tonight)
issued at 325 am CDT Thursday Jul 31 2014

Subtle middle level wave is dropping into north central South Dakota this morning
is firing a few isolated showers and thunderstorms near a weak
surface low in central South Dakota...mainly in areas west of the
James River. As the wave slowly drops southeast through this
afternoon...expect cumulus field associated with this system to
expand across the forecast area in the heat of the day. The isolated
showers and thunderstorms will continue tracking through mainly our
western counties through the morning hours...then expand into mainly
the southeastern portion of the forecast area late morning through
the afternoon as the wave arrives. As has been the case of
late...moisture...lift and support is very limited with this feature
but cool air aloft will allow enough instability to keep isolated to
widely scattered showers and thunderstorms going. Quantitative precipitation forecast amounts will
be minimal and no area should expect a total wash out by any means
with the short lived activity. Otherwise...partly cloudy
skies...light winds and pleasant temperatures will persist today.
Highs will be similar to yesterday in the upper 70s and lower to middle
80s.

With the passing of the shortwave and loss of daytime
heating...showers will end in the evening and clouds decrease. Light
and variable winds persist overnight with lows falling into the middle
50s to near 60.

Long term...(friday through wednesday)
issued at 325 am CDT Thursday Jul 31 2014

Another weak shortwave dropping southward on a northwesterly
upper level flow could trigger isolated thunderstorms in our east
on Friday...though moisture is meager and forcing is weak so will
probably not see much of anything. 850 mb temperatures will warm a
couple of degrees over today...so looking at highs generally 80s
across the area.

An upper level ridge begins to build into the region for the weekend
into the beginning of next week...bringing warming and finally
driving temperatures to above normal levels by Sunday and Monday with
highs into the middle 80s to around 90. Precipitation chances through
the weekend look to be low and hit and miss if they were to occur...so
with the lack of any significant forcing and warming middle levels kept
it dry. Toward the middle of next week a shortwave rounds the ridge
and drops into the northern plains in the Tuesday to Wednesday time
frame. This will lower temperatures back to around normal to just
below normal and bring better chances of precipitation to the
area for those days.

&&

Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1230 PM CDT Thursday Jul 31 2014

Generally VFR through the period. A few isolated showers or
thunderstorms are possible this afternoon and again tomorrow...but
coverage expected to be too low to mention in the tafs at this time.

&&

Fsd watches/warnings/advisories...
South Dakota...none.
Minnesota...none.
Iowa...none.
NE...none.
&&

$$

Short term...
long term...jm
aviation...chenard

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