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000
FXUS62 KILM 242137
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
537 PM EDT Sun Sep 24 2017

.SYNOPSIS...
Hurricane Maria is expected to remain offshore as it moves very
slowly north, with its center passing within 250 miles of the
Cape Fear coast through Wednesday. Hazardous beach and boating
conditions will continue for much of the week. A cold front is
expected to reach the area Friday, bringing cooler weather for
next weekend.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 230 PM Sunday...While diurnal cumulus has formed with the
strong insolation this afternoon the low-level band of convergence
far offshore has been the nearest focus for showers today.
Otherwise, the H85-H5 layer has been dry and the low-level
trajectory will keep the showers at bay through tonight. These
showers could approach the Cape Fear area and coastal northeast SC
later Monday. Followed blend of MAV/MET numbers tonight and Monday.
Breezy conditions expected to continue especially along the coast
where the northeasterly pressure gradient increases. Strong rip
currents and high surf will persist at all area beaches through
Monday.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 300 PM Sunday...This period will basically function off the
indirect and possible direct effects generated by Hurricane Maria as
she tracks northward during this week over the open waters of the
Atlantic remaining well offshore from the U.S. mainland which
includes the local FA. The exception is the Outer Banks of NC which
will see Maria`s closest approach.

Once the generally troffiness associated with Jose off the Mid-
atlantic and New England coasts dissipates, modest to strong upper
level ridging will take it`s place. This will slow Maria`s forward
northward movement with models indicating her well offshore from
Cape Lookout to Cape Hatteras latitude by Wed morning. With this
track, enough of it`s expansive pressure field and moisture will
result in breezy NNE-NNW winds across the local area during this
period with the hiest winds along the immediate coast, especially
from Cape Fear northward.

As for pcpn chances associated with Maria, locations across coastal
southeast NC will be under a slight RW- chance beginning late Mon
night thru Tue. The ILM SC CWA will remain pcpn free this period.
With the mid-levels remaining quite dry thruout this period, the
cirrus shield associated with Maria will encompass all of the ILM
CWA. The lower levels will see a moisture increase across all
locations, with the deeper low level moist profile across areas from
Cape Fear northward. PCPN will be produced from the low level clouds
and remain below 0.10 inches total thruout this period. Temperatures
will continue to run at 1 to possibly 2 categories above the climo
norms. The thick cirrus shield and eventual low level clouds will
limit highs across the Cape Fear northward region, but still above
climo.

Beaches along the entire ILM CWA will be under a High Surf Advisory
and High Rip Current threat for the majority of this period. This a
result of 6 to 9 foot long period Maria swell affecting the local
waters for an extended period of time.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 300 PM Sunday...Maria, forecast to be well to the east-
northeast of the area at the onset of the period, will continue
moving north and east away from the area.  A cold front will
drop into the area Thursday night and move out to sea Friday,
ushering in cooler and drier air for the weekend.

Outside of a small chance of showers Wednesday, mainly over
northeast sections of the forecast area, the extended range
looks mainly dry.  High temperatures in the mid 80s to around 90
Wednesday and Thursday will cool to the mid 70s by Sunday.  Min
temperatures in the upper 60s to lower 70s Wednesday night
will cool to the upper 50s to lower 60s by Saturday night.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
As of 18Z...High pressure will maintain VFR conditions through
tonight however MVFR CIGs are possible as stratus possibly
streams into the coastal terminals during Monday. A few -SHRA
possible at the coastal terminals as well by later Mon, not
enough confidence to include in the TAFs at this point. Breezy
northeasterly winds at the coastal terminals as well.

Extended Outlook...Brief MVFR conditions may develop at the coastal
airports as Hurricane Maria brings isolated showers Tue-Wed as it
moves N, with its center remaining well offshore. N winds may
increase to 15 to 25 kt Monday Night through Wednesday.

&&

.MARINE...
NEAR TERM /THROUGH MONDAY/...
As of 230 PM Sunday...High pressure to the north and Maria
moving northward from the southeast will result in a
continuation of northeast flow across the coastal waters, with
the highest speeds across the waters off Cape Fear. The flow
will slowly back to the north-northeast during Monday as the
hurricane moves farther north. Large swells coupled with the
waves from the northeasterly fetch will create hazardous
maritime conditions through the period. Widely scattered showers
across the outer waters tonight could increase in coverage
during Monday.

SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 300 PM Sunday...SCA conditions will continue across the
area waters thruout this period. With the local waters on the
westward side of Hurricane Maria as she tracks northward,
remaining well offshore from the local area, wind directions
will run from the NNE- N Mon night into Tue, and from the NNW-NW
there-after as Maria`s eye moves north of the local latitude.
The sfc pg associated with Maria, will be conducive to wind
speeds in the 15 to 25 kt range south of Little River Inlet and
20 to 30 kt north of this Inlet. Could see Gale Gusts from Cape
Fear northward thruout this period.

Significant seas this period will be dominated by the 13-16 second
period, ESE-SE Maria Swell. The short period locally produced NNE-
NNW wind waves will create choppy conditions on top of this swell.
This a result of a limited fetch. The area inlets to and from the
Atlantic as well as the mouths of Cape Fear River and Winyah Bay
will experience dangerous and hazardous navigating conditions.

LONG TERM /WEDNESDAY THROUGH FRIDAY/...
As of 300 PM Sunday...Northwest winds of 15 to 25 KT Wednesday
morning will diminish to 10 to 15 KT by Thursday morning.  A
shift to the north then northeast will occur Friday and Friday
night.  Seas of 4 to 7 FT south and 7 to 9 FT north Wednesday
AM will gradually subside through the period, falling to
2 to 3 FT by Friday.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...High Rip Current Risk through Tuesday evening for SCZ054-056.
     High Surf Advisory until 9 PM EDT Tuesday for SCZ054-056.
NC...High Rip Current Risk through Tuesday evening for NCZ106-108-
     110.
     High Surf Advisory until 9 PM EDT Tuesday for NCZ106-108-110.
MARINE...Small Craft Advisory until 6 PM EDT Wednesday for AMZ250-252-
     254-256.

&&

$$

NEAR TERM...SRP
SHORT TERM...DCH
LONG TERM...RAN
AVIATION...SRP