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Area Forecast Discussion
National Weather Service Raleigh NC
321 PM EDT SUN AUG 28 2016

.SYNOPSIS...
High pressure will persist over the western Piedmont through Monday night.
An area of low pressure over the Atlantic will drift west toward the
Carolina coast through Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 321 PM Sunday...

A zone of weak moisture convergence, being pushed west-sw by an
upper level low off the SC coast, will maintain a threat for
scattered showers and storms along our far eastern-se counties
through sunset. A few of these showers may progress as far west as
the highway 1 corridor by 5 or 6 PM but deeper moisture and better
lift will remain confined to our far east-se counties.

After sunset, this moisture confluent zone will remain anchored near
the eastern periphery of our forecast area. Thus, could see isolated
showers anytime during the overnight hours east of the I-95
corridor. Expect a deck of low clouds/stratus to develop to our east-
ne and overspread into our eastern Piedmont and coastal plain
counties by sunrise.

The western Piedmont will remain under the influence of an area of
high pressure near the surface and aloft. This will maintain mostly
clear skies. 

Overnight temperatures will vary from the upper 60s to near 70
northwest to the lower 70s southeast. 

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
As of 321 PM Sunday...

Little change in the weather pattern across central NC Monday and
Monday night. An area of high pressure will continue to extend
across the western Piedmont, maintaining dry weather and seasonable
temps. Moisture axis associated with the mid/upper level trough off
the southeast U.S. will maintain a threat for showers and
thunderstorms with most of the convection confined to the coastal
plain and eastern sandhills. A few showers will likely be occurring
in the morning though the bulk of the activity will occur during the
mid afternoon into the early evening hours. 

Cloudiness over the eastern counties will inhibit sunshine for most
of the morning, delaying temp recovery. Thus, should see a fairly
uniform max temp field Monday afternoon with highs in the 85-90
degree range. 

Monday night will see conditions comparable to tonight with most of
the cloudiness confined to the coastal plain and mostly clear skies
in the western Piedmont. Min temps upper 60s west-nw to the lower
70s se.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
As of 243 PM SUNDAY...

A couple of systems to deal with during the long-term period, the
first of which will be what comes of TD8, now located about 400mi SE
of KHSE. Based on latest model guidance and NHC track, it appears
that system will remain far enough to our east to preclude any
impacts to central NC.  Assuming no changes, the Tue-Wed time frame
looks to be mostly-dry with subsidence on the north and west side of
that system resulting in below-climo pops for central NC, along with
temps remaining several deg above normal, despite NE flow. 

The next system will be a short wave trough and assoc sfc cold front
approaching from the north on Wednesday night and moving across our
CWA on Thursday. While the sfc boundary coupled with mid-upr forcing
assoc with a departing jet streak will provide adequate forcing for
ascent, NW pre-frontal low to mid-level flow suggests that the best
moisture will be found closer to the coast.  Thus will feature a
west-east pop gradient for the day and evening hours Thursday,
highest pops east. Temps will continue to remain above normal until
the front moves through. 

Lastly, a lot of uncertainty remains for next weekend as it relates
to what's now the disturbed weather over the FL straights. Models
have been bouncing around with it's movement, and whether or not
it's going to make a run up along the SE coast late in the week into
next weekend. Of course a lot can change between now and then, so
for now, will keep pops at or below climo with near normal temps
across our area for next weekend, while keeping a close eye on
model trends.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
As of 1245 PM Sunday...

There is high confidence that VFR conditions will prevail across the
western Piedmont of central NC through Monday night as an area of
high pressure at the surface and aloft extends overhead. Surface
winds out of the northeast may be breezy at times Monday, gusting
between 14-18kts. 

Along and east of the highway 1 corridor, periods of cloudiness will
occur, resulting in MVFR/IFR ceilings, with the lowest ceilings
expected between 09Z-15Z Monday. A few showers may skirt in vicinity
of KFAY and KGSB , and south of KRWI this afternoon through early
evening, and again Monday afternoon. The difference in pressure
between the high to the west and the approach of tropical depression
to our east will yield breezy northeast winds Monday of 10-14kts
with occasional gusts near 20kts. 

The above conditions expected to occur again Tuesday. Forecast
confidence lowers for the remainder of the work week as model
guidance offering varied solutions concerning the approach of a low
pressure system from the south-southwest, and a cold front from the
nw. At this time, the risk of adverse aviation conditions appear
greater at KFAY and KRWI, and less so at KRDU, KGSO, and KINT.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...np 
AVIATION...WSS

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