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Area forecast discussion 
National Weather Service Wilmington NC
127 PM 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 1045 am Thursday...welcome (?) To the peak of the heat wave.
Not only is today going to be about 2 degrees higher than
yesterday but some very high dewpoints have pooled into coastal NC
and with a west-southwest wind they should stay there. Yesterday it seemed
that they would mix out some in the afternoon heating of the day
but 12z raobs from both mhx and chs show weaker hydrolapse rates
than what yesterday's guidance portrayed. It seems likely then
that only a minor drop in dewpoints is slated for this afternoon.
So now coastal NC counties along with Bladen and much of Columbus
should see heat indices in excess of 110 degrees. Have upgraded
the advisory to a warning in those locales. No other changes to
the forecast.


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 /18z Thursday through Monday/...
as of 18z...VFR through the valid taf cycle. Runway gusts to 19
knots between west and SW through 0z. West-southwest-SW winds diminishing to 8 knots
or less coastal terminals after 1z, and 3-5 knots inland airports. After
15z Friday, west-west-southwest gusts 17-19 kt, tonight, isolated 5sm br between 09z-
12z inland, although anticipated coverage and confidence level
does not warrant inclusion at terminals.

Extended outlook...VFR. Isolated/scattered afternoon convection Sunday and
Onward through the forecast will create fleeting and localized


near term /through tonight/...
as of 1040 am changes to the forecast. Conditions
pretty quiet and typical of the time of year, albeit hot. Previous
discussion still applies:

As of 615 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 until 8 PM EDT this evening for scz017-023-024-
NC...heat advisory until 8 PM EDT this evening for ncz087-110.
Excessive heat warning until 8 PM EDT this evening for ncz096-



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

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