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000
FXUS62 KRAH 250729
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
329 AM EDT Mon Sep 25 2017

.SYNOPSIS...
High pressure centered over the Great Lakes and northern Mid
Atlantic states will extend south into our region today. Hurricane
Maria is forecast to move north through the western Atlantic,
paralleling the SE Coast through midweek.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 305 AM Sunday...

High clouds continue to stream into the area this morning in
association with Hurricane Maria, which is located well off the
southeast U.S. coast. Meanwhile, surface high pressure will continue
to extend into the area from the north today. This will yield a
continuation of dry conditions, though increasing cloud cover, with
even some lower clouds moving into eastern portion of the area
today. In addition, the pressure gradient between the high to our
north and Maria will also begin to tighten, producing wind gusts in
the mid to upper teens across the area. High temps are expected to
range from the lower to mid 80s east to the mid to upper 80s west.

Low level moisture will further increase across the area, especially
eastern portions of central NC tonight as Hurricane Maria slowly
lifts northward offshore of the Carolinas. This will allow for some
low stratus to spread eastward into central NC, though generally dry
conditions are expected to continue. Low temps are expected to be in
the mid to upper 70s,

&&

.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
As of 325 AM Monday...

Hurricane Maria is expected to slowly lift northward, while
remaining a couple hundred miles off the NC coast. Thus, central NC
will remain well west of the track of the hurricane, and resulting
see only minimal impacts. In fact most locations across our a
forecast area will remain dry, with only a few light shower
associated with some weakening outer bands possible Tuesday-Tuesday
night across our far eastern Coastal Plain counties. The main
impacts will be mostly cloudy to overcast skies and some breezy
winds, with gusts of up to 30 mph or so (mainly across the Coastal
Plain and eastern Sandhills - generally along/near the I-95 corridor
and eastward). High temps are expected to be in the lower to mid 80s
and lows in the upper 60s to near 70.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 345 PM Sunday...

Tue through Thu night: Hurricane Maria is expected to drift slowly
northward off the NC coast Tue-Wed, before getting caught up in the
westerlies and taking a turn NE and out to sea Thu. The official
forecast track follows the op GFS more closely than the ECMWF, which
tracks Maria`s center a bit closer to the NC and about 18 hrs slower
than the GFS by Thu. Will hew more closely to the op GFS for
sensible weather. Based on the latest NHC wind radii forecasts, we
are very unlikely to see tropical storm force winds into our
forecast area. However, momentum transfer noted on forecast
soundings suggests that frequent gusts to 20-25 kts are likely in
our eastern third, especially when Maria`s center makes its closest
approach Wed. Skies Tue should trend to fair west, with streaks of
thin high clouds streaming off the top of Maria northwestward over
NC, with partly to mostly cloudy skies east where greater low level
influx of Atlantic moisture should result in scattered to broken
stratocu. As Maria tracks up to and north of the latitude through
central NC, the backing of low level winds to be from a more
northerly or northwesterly direction should help draw drier air back
in, such that clouds should thin out Wed, and likely be primarily
partly cloudy through Thu. Shower chances appear to be small, with
models generally confining small chances of measurable precip to the
east. Will continue with isolated shower pops Tue through early Thu,
as far outer bands may work into the Coastal Plain at any time.
Highs 80-86 Tue and 81-89 Wed, with narrow ridging aloft NW and then
W of Maria and thicknesses 10-15 and 15-20 m above normal
respectively. By Thu/Thu night, broad mid level troughing over much
of NOAM (all but the far S and W) begins to dig over the Upper
Midwest, pushing a moisture-starved cold front to the SE, over the
NC mountains and through the state late Thu through Thu night.
Expect highs of 83-90 Thu with thicknesses likely to be nearly 20 m
above normal. Lows in the mid 60s to lower 70s Tue night and Wed
night, slipping to the low-mid 60s post-front Thu night.

Fri through Sun: The digging mid level trough shifts eastward over
the weekend, while cool high pressure drifting from the Upper
Midwest across the Great Lakes to the Northeast ridges down through
NC. The GFS develops a baroclinic zone near the SE Coast, along
which low pressure tracks. While this is far from certain to occur,
given some disagreement in the models, will still leave in a low
chance of showers over the SE, mainly late Sat through Sat night,
still below climatology. Otherwise, expect fair to mostly sunny
skies. Highs in the upper 70s to lower 80s Fri, then in the 70s
Sat/Sun, making for a pleasant fall weekend. -GIH

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/
As of 210 AM Monday...

24 Hour TAF Period: VFR conditions are expected to continue early
this morning through at least daybreak. A band of MVFR clouds of
around 1500-3000 ft are expected to spread eastward into eastern
portions of central NC. This may result in a period of MVFR cigs at
KFAY and KRWI from mid evening through late afternoon/early evening.
Further west, expect VFR conditions will continue as surface high
pressure extends southward into the area. Otherwise, expect dry
conditions to continue, with increasing northeasterly winds today,
with perhaps a few gusts into the 15 to 20 mph range as Hurricane
Maria slowly lifts northward off the southeast U.S. coast.

Outlook: The closer approach of Hurricane Maria to the coast will
bring chances for some shower activity as well as some lower
ceilings to the eastern portions of the forecast area Monday night
through Thursday.

&&

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

&&

$$

SYNOPSIS...BSD/CBL
NEAR TERM...BSD
SHORT TERM...BSD
LONG TERM...Hartfield
AVIATION...BSD/Ellis