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000
FXUS62 KRAH 190730
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
330 AM EDT Wed Sep 19 2018

.SYNOPSIS...
High pressure will build in from the west today and settle over the
region through the rest of the work week, bringing dry and
unseasonably warm conditions.

&&

.NEAR TERM /TODAY AND TONIGHT/...
As of 240 AM Wednesday...

The surface and mid level troughs are heading off the coast as high
pressure builds in from the west. Deep subsidence and drying will
take place today, ensuring plentiful sunshine as cloudiness now over
extreme E sections departs, with only a few flat afternoon cu
forming with heating. Thicknesses around 15 m above normal support
highs in the mid-upper 80s with heating. Then this evening into
tonight, cloudiness and convection now over N IL/OH extending NE
over Lakes Erie/Ontario will drop SSE, reaching our N central and NE
sections this evening. Any moisture with this should be rather
shallow due to the mid level ridging, so expect no more than some
cloudiness with perhaps an isolated light shower or two, and this
will be reflected in the forecast with an uptick in clouds but with
sub-14% pop. Lows mainly in the mid to upper 60s. -GIH

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 315 AM Wednesday...

This will overall be a continued quiet weather period with above
normal temps. The core of the mid level ridge will drift from the
Mid-South / Gulf states to a position over the Carolinas through
Fri, before weakening in place Fri night. A narrow surface ridge
centered well to our N will build in from the N and NE through early
Fri, before it shifts eastward and become supplanted by lee
troughing and a light SW flow. Clouds during this period should be
limited to a few afternoon convective clouds, although a period of
low level moist upglide Thu evening and night may bring partly to
mostly cloudy skies over the W Piedmont. Above-normal thicknesses
still favor highs in the mid to upper 80s and lows in the mid to
upper 60s. -GIH

&&

.LONG TERM /SUNDAY THROUGH TUESDAY/...
As of 330 AM Wednesday...

Saturday and Sunday: A cold front will approach from the northwest
on Saturday and pre-frontal convection will move into the northern
counties by Saturday afternoon/evening but areas south of US-64
could remain dry on Saturday. Not a lot of instability to work with
according to forecast soundings so an isolated or scattered
thunderstorm is possible across the north but otherwise general
showers are expected. Light rain could linger into the overnight
hours across the north as the front gradually tries to move
southward. Still warm on Saturday with highs in the mid to upper
80s. Sunday the front will continue southward but likely stall out
somewhere over the state. A little better chance for precipitation
Sunday afternoon but again not much instability in the soundings.
Also anticipating a high temperatures gradient somewhere across the
area with low 80s across the north with mid 80s in the south.

For early next week, surface high pressure developing over new
England could cause a cold air damming event over the area which
would be characterized by overcast skies and cooler temperatures
with the chance for light rain, especially in the NW Piedmont to
lock in the CAD. There is some model disagreement on this scenario
however and while the ECMWF has the CAD locked in, the GFS is not
confident in how far south the wedge front will get. If it does get
into the area, high temperatures in the NW Piedmont could top out
sub 80 degrees with again mid 80s across the southeastern counties.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As of 145 AM Wednesday...

VFR conditions will dominate central NC terminals for the next 24
hours, as high pressure builds in from the west. RWI may see a
couple of hours of MVFR fog early this morning during the 08z-13z
time frame. Skies will be mostly clear, with just a few VFR clouds
pushing into N/NE sections (RDU/RWI) toward the end of the forecast
period.

Looking beyond 06z Thu, a few VFR clouds and perhaps an isolated
shower may pass near RDU/RWI 06z-12z. VFR conditions will remain
dominant through Sun at all sites, although INT/GSO could see a
period of MVFR/IFR conditions late Thu night into Fri morning as
some low level moisture banks up against the higher terrain. We`ll
also see the chance for typical scattered afternoon/evening storms
increase by Sat/Sun. -GIH

&&

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

&&

$$
SYNOPSIS...Hartfield
NEAR TERM...Hartfield
SHORT TERM...Hartfield
LONG TERM...Ellis
AVIATION...Hartfield