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Area forecast discussion 
National Weather Service Columbia SC
250 PM EDT Sat Jul 30 2016

upper level ridge continues to slide into the Atlantic Basin as
the upper trough digs across the MS River Valley into the Ohio
River valley. A series of short waves rotating through the base of
the trough will result in increasing chances of thunderstorms over
the next several days.


Near term /through tonight/...
a broad upper trough over the MS River Valley will slowly shift
east into the Great Lakes region and Ohio River valley.

Precipitable water around 2.0 inches with weak to moderate
instability over the forecast area. A series of weak short waves
is forecast to cross the area this afternoon into the evening.
Meso-analysis indicated a surface trough across the area with
scattered showers and thunderstorms across the Piedmont and csra.
Scattered convection should continue to move east across the
midlands through this evening. Severe thunderstorm threat remains
low with main potential this evening from damaging wind gusts.
Expect thunderstorm coverage to diminish with sunset...however
with the short waves continuing to move into the area ahead of the
upper level trough expect a few thunderstorms to persist into

Afternoon highs will be in mid 90s to around 100 degrees with
heat index readings in the 103 to 107 range. Low temperatures
tonight will be in the mid 70s.


Short term /Sunday through Monday night/...
an upper level trough will continue to shift eastward through
Monday as a weak surface boundary approaches from the north.
Moderate instability and multiple disturbances moving through the
upper trough support and increasing chance for thunderstorms.

Scattered convection is expected Sunday afternoon in a moist,
moderately unstable airmass. Lingering upper level ridging and
lack of a strong forcing mechanism at the surface should keep any
convection scattered. Although mid-level temperatures will be
slightly cooler than previous days, the threat for severe storms
is low. A skinny area of positive buoyancy in the forecast
soundings suggest pulse type thunderstorms with weak updrafts.
Models do show an upper level shortwave moving through the area
Sunday afternoon/evening which may help promote development. The
GFS indicates the potential for a sea-breeze to move inland
triggering additional convection Sunday evening. The shortwave
may allow for storms to linger overnight. Highs will be in the mid
to upper 90s with lows in to mid 70s.

Monday, as the upper trough amplifies and moves further east, the
associated surface boundary will enter the region. Convergence
ahead of the boundary will allow for thunderstorms to develop in
the forecast area. 500 mb temperatures around -8 degrees will be
more conducive for strong thunderstorms Monday afternoon. Given
the cooling mid-levels and a higher confidence in thunderstorm
coverage than previous days, highs should be in the low to mid-
90s. Cannot rule out the chance for thunderstorms into the night
with models indicating the possibility of multiple shortwaves
moving through the area.


Long term /Tuesday through Saturday/...
the upper level trough will remain over the eastern US in the
mid-term with ridging moving back over the area towards the end
of the period. A surface trough may linger in the region through
the week keeping the chance for thunderstorms in the forecast.
Temperatures are expected to remain a few degrees above normal
during the period with highs in the mid to upper 90s and lows in
the low to mid 70s.


Aviation /18z Saturday through Thursday/...
VFR conditions expected outside of scattered...mainly diurnal...

Scattered showers and thunderstorms in the vcnty of dnl/ags at
17z expected to continue developing east to affect the midlands
taf sites this afternoon into the evening. Convection should
diminish with sunset. Southwest winds around 10 knots will also
diminish with sunset.

Cannot completely rule out isolated convection overnight given
moist and unstable atmosphere. However...showers and
thunderstorms will once again increase in coverage Sunday

Extended aviation outlook...low potential for restrictions in
afternoon and evening convection each day.


Cae watches/warnings/advisories...


near term...99
short term...99
long term...99

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