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Area forecast discussion 
National Weather Service Wilmington NC
124 am EDT Sat Jul 30 2016

Synopsis...
high pressure will continue to bring oppressive heat and humidity
to the region through Saturday. The high will begin to break down
beginning Sunday. A cold front will drop slowly across the area
Tuesday into Wednesday bringing good chances for thunderstorms.
Cooler temperatures will follow for the middle and end of next
week.

&&

Near term /until 6 am this morning/...
as of 1225 am Friday...a couple small clusters of showers
continue to push eastward across Columbus County and expected
these to push off the coast in the next several hours. Also, a
fading shower may sneak into western Darlington County by 06 UTC.
The 03 UTC hrrr is showing all the showers should have exited area
by 10 UTC. So will leave a 20 percent chance of a shower or
thunderstorm for areas mainly north of a Florence to Southport
line.

No changes were made to the temperature forecast.

&&

Short term /6 am this morning through Sunday night/...
as of 330 PM Friday...the heat indices will kick back up above
advisory levels once again on Saturday. It appears the Atlantic ridge
may push back toward the northwest a bit with heights rising a
bit and 850 temps up a couple of degrees, mainly eastern two
thirds of area. Temps should reach the mid 90s for highs.
Therefore we will once again issue heat advisories mainly I-95
corridor east where dewpoint temps will increase as aftn sea
breeze draws Atlantic moisture inland. The main focus for
convection will be along Piedmont trough and along sea breeze
boundary. The overall chance for convection will increase and may
decrease the overall length of heat advisory, but for now, have
issued it from noon to 8 PM. Some needed rain and may temper some
of the heat.

By Sunday, Atlantic ridge gets pushed south and east a little
farther as mid to upper trough makes a little headway east. The
fight between the ridge and trough will be tricky in delineating
the area of greater convective potential. Overall expect moisture
to increase through the atmosphere and greater potential for
convection mainly along Piedmont trough inland and sea breeze
boundary. This should also keep temps from reaching heat advisory
criteria with greater amount of clouds and shwrs/tstms. Temps
should reach into the low to mid 90s on Sunday.

&&

Long term /Monday through Friday/...
as of 300 PM Friday...significant airmass change occurs...finally as
the calendar flips to August. The tremendous heat and humidity
through which we have been suffering will persist one last day
Monday with highs in the 90s and high humidity once again, but a
return to seasonable or even slightly below normal temps is forecast
by mid week. The cause of this change is a sharp mid-level trough
driving a cold front through the Carolinas Tuesday and Wednesday.
Guidance is in agreement this front will slow across the area, but
eventually will sink south of the region on Wednesday as the upper
ridge breaks down. Guidance can frequently be too aggressive and
quick with the breakdown of these ridges, so will lean on the slower
solution and dissipate the front Wednesday just south of the area to
blend with inherited, but much cooler temperatures are forecast
Tue/Wed/Thu with a slow return to warmer temperatures possible late
in the period. Along with these cooler temperatures, tstms should
become more numerous Monday night through Wednesday associated with
the fropa, decreasing back to seasonable pop at the end of the
week.

&&

Aviation /06z Saturday through Wednesday/...
as of 06z...isolated rain showers/thunderstorms and rain overnight and the potential for
patchy areas of marginal MVFR towards morning. Otherwise expect VFR
through the valid taf period with scattered rain showers/thunderstorms and rain Saturday
afternoon.

Latest radar imagery depicts isolated light showers moving across
the area. Do not anticipate any restrictions to arise from this
activity. With the combination of light winds and available low
level moisture from isolated showers, this may allow for patchy
areas of fog to develop towards morning, especially inland.
However, given lower confidence have not introduced into going
forecast at this time. Any fog that does develop could potentially
create marginal MVFR. After daybreak, VFR will prevail across the
forecast area with southwest winds around 10 kts, with higher
gusts and scattered convection in the afternoon. Anticipate
rain showers/thunderstorms and rain activity to taper off Saturday night, with light winds
and gradually clearing skies.

Extended outlook...isolated to scattered afternoon and evening
convection each day may result in localized MVFR/IFR conditions.
Each morning may also observe brief MVFR/IFR from fog and/or low
ceilings. Otherwise, expect VFR.

&&

Marine...
near term /through tonight/...
as of 1220 am Saturday...no changes to previous forecast
discussion. No apparent nocturnal jetting expected tonight.
Southwest breezes have weakened considerably from earlier in the
eve as the temp differential between land and water has relaxed
with the land cooling 10 to 15 degrees from the highs of the day.
Sustained SW winds will be on the order of 10 to 15 kt with gusts
up to 20 kt late eve and overnight. Seas will be 2 to 4 ft.

Short term /Saturday through Sunday night/...
as of 330 PM Friday...the Bermuda high and Piedmont trough will
continue to be main players with a SW wind 10 to 15 knots through
much of the period. As mid to upper trough pushes a cold front
into North Carolina Sun night the gradient should tighten and
winds will increase to 15 to 20 knots. Seas will remain 2 to 4
feet through the period.

Long term /Monday through Wednesday/...
as of 300 PM Friday...Bermuda high pressure remains dominant one
last day Monday before a mid- level trough drives a slow moving
cold front across the waters through mid-week. This causes a wind
shift, so after 10-15 kts of SW winds on Monday, the gradient
becomes diffuse as the front drops south and weakens, with winds
gradually becoming NE at 5-10 kts by Wednesday. Highest seas will
be Monday with the southeast swell and SW wind wave producing 3-4 ft
seas. Wave heights will fall slowly Tuesday, and then down to 2-3
ft Wednesday with a confused spectrum likely as a NE wind wave
develops atop the residual southeast swell.

&&

Ilm watches/warnings/advisories...
SC...heat advisory from noon today to 8 PM EDT this evening for
scz032-033-039-053>056.
NC...heat advisory from noon today to 8 PM EDT this evening for
ncz099-105>110.
Marine...none.

&&

$$

Near term...Hawkins
short term...rgz
long term...jdw
aviation...sgl

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