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Area forecast discussion 
National Weather Service Wilmington NC
314 am EDT Thursday Jul 28 2016

high pressure will continue to bring oppressive heat and humidity
to the region through Saturday. The high will begin to break down
this weekend leading to good chances of showers and thunderstorms
beginning Sunday and continuing through the middle of next week.


Near term /through tonight/...
as of 315 am Thursday...another hot day for the region as high
pressure at the surface to the south and the Piedmont trough
continue. At 850 mb temperatures will run between 19.5 and 20.5
degrees celsius. This will allow for the maximum temperatures
to range between 97 to 99 degree over much of the inland areas.
Will see mid 90s closer to the coast and a tad cooler if you are
lucky enough to be at the beach.

The hot temperatures combined with the dewpoints in the lower 70s
inland to the mid 70s at the coast will help to raise the heat
indices into the 106 to 109 degree range. As expected a heat
advisory will be issued again for the area from 11 am until 8 PM.

Looking at the model sounding from the GFS and NAM it appears
convection in most area will be hard to generate so will keep
the pops just below 20%.


Short term /Friday through Saturday night/...
as of 315 am Thursday...the high pressure aloft is being
projected to being shunted to the southeast and a weak 500 mb
trough will setup over the Ohio Valley. This should allow for only
slight cooling but should allow diurnal convection to develop on
Friday and Saturday. So will continue with a slight chance of
thunderstorm but widespread rainfall is not expected.

Maximum temperatures are expected only to drop into the middle 90s
during the day and the heat indices are expected to fall from todays
106 to 109 range to 103 to 105 range.


Long term /Sunday through Wednesday/...
as of 315 am Thursday...its shaping up to be a somewhat unsettled
period as the mid level ridge will be relenting to a subtle and
slow moving trough over the Tennessee Valley. The trough actually
deepens through Tuesday and then basically fills. At the surface
the second half of the period will feature a cold front moving
into the area and dissipating as well. Long story short, good
chances of showers and thunderstorms will be the story each day.
Difficult to say what period pops will be highest but it seems the
coupling of the front late Monday into Tuesday with the deepening
trough makes more sense. The same time is probably more conducive
to severe weather with an increase in shear although this time of
year it seems fair game anytime. There is a bit of cooling now
showing up at least in the GFS regarding thermal profiles as 850mb
temperatures drop off a couple of degrees Wednesday. Still, most
of the slight cooling trend is courtesy of the convection/moisture.


Aviation /07z Thursday through Monday/...
as of 06z...once again a persistence forecast for the aviation
community. Mid level ridge will actually strengthen a bit through
the period with high confidence in VFR conditions. Some gustiness
expected once again today as well via deep mixing inland and the
sea breeze for the coastal terminals.

Extended outlook...isolated to scattered afternoon convection
through Sunday may create brief periods of MVFR/IFR. Otherwise
expect VFR.


near term /through tonight/...
as of 315 am Thursday...high pressure and the Piedmont trough over
the Carolinas will continue to produce southwest winds of 15 knots
today with 3 ft seas. A southeast swell of 1 ft every 8 seconds will
continue today with the wind wave of 2 to 3 feet every 5 seconds.

Short term /Friday through Saturday night/...
as of 315 am Thursday...very little change with the surface pattern
except for a slight tightening of the pressure gradient as the
Piedmont trough shifts closer to the coast on Friday and Saturday.
Southwest winds of 15 to 20 knots will continue with seas of 3 ft.
There may be an occasional 4 ft wave at 20 miles off the coast
mainly north of Little River on Friday and Saturday.

Long term /Sunday through Monday/...
as of 315 am Thursday...southwest winds of 10-15 knots will continue
across the waters. Better chances for some convecton to distort
local wind fields however. Significant seas, absent any appreciable
swell component will be 1-3 feet.


Ilm watches/warnings/advisories...
SC...heat advisory from 11 am this morning to 8 PM EDT this evening
for scz017-023-024-032-033-039-053>056.
NC...heat advisory from 11 am this morning to 8 PM EDT this evening
for ncz087-096-099-105>110.


near term...drh
short term...drh
long term...shk

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