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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 231523
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
1123 AM EDT Sat Sep 23 2023

.SYNOPSIS...
Tropical Storm Ophelia, lifting north, has made landfall at
Emerald Isle early this morning. Ophelia will continue pushing
further inland and northward, away from the forecast area this
morning thru tonight. Rainfall and strong gusty winds will peak
this morning, particularly across Southeast NC. Improving
conditions are expected later today through Sunday as Ophelia
lifts further north and high pressure fills in behind.
Generally dry and seasonable weather is expected for the first
half of the upcoming work week as high pressure remains in
control.

&&

.UPDATE...
-- Changed Discussion --
As of 11:15 AM EDT, All Tropical Storm Warnings over land and
the marine zones have been cancelled. All associated products
have been updated. Gusty winds will continue today under mostly
cloudy skies, but no more tropical-storm-force winds expected.

Over the coastal waters, a couple of gale-force gusts are
possible over the next hour or two, particularly from Cape Fear
to Surf City out 20nm. However, these gusts are not frequent or
consistent enough for a Gale Warning. Opted for a Small Craft
Advisory for all coastal waters that we cover, ranging from
South Santee to Surf City.

Finally, we have published two separate Public Information
Statements (PNSs) that provide summaries of rainfall totals and
peak wind gusts from this event. Go to
https://forecast.weather.gov/product.php?site=ilm&issuedby=ILM&product=PNS
to see these statements.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
ATTM, Ophelia`s center is just offshore from the Crystal Coast
of NC and is progged to make landfall early this morning in this
vicinity. The worse conditions from this cyclone will occur now
thru mid-morning. Once inland, Ophelia will quickly transition
into a weakening phase and will continue to push further away
from the FA for the remainder of this forecast period. Look for
decreasing winds especially this afternoon and onwards. So much
dry air has entrained into this system, with the only
appreciable pcpn amounts coming from the convection on the
western side of the center that may possibly affect the Cape
Fear area thru this morning. Am reluctant to keep the FFA going
other than for the convection on the western side of the center
this morning. Once this feature lifts north of the area later
this morning, the FFA will likely be dropped if not sooner. The
same will likely occur with the Tropical Storm warning itself.
For the time being, will deal with a low overcast sky for much
of the day with pcpn more scattered in nature and becoming
light, intensity wise. Skies to improve late this aftn and
especially tonight with just enough mixing keeping any
widespread fog at bay eventhough sfc dewpoint depressions less
than 2 degrees F late in the pre-dawn Sun hrs. Max temps today
will remain in the upper 60s away from the coast given the
overcast and winds, except low 70s at the coast and southernmost
portions of the FA. Mins to run in the upper 50s, except 60-65
at the coast.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A bit of a surface trough early Sunday trailing from Ophelia
but washes out by midday. Mid level troughiness lingers longer
but with dry advection behind the storm it should do little more
than bring a few clouds as there is some moisture in the
5-10kft range. Southwesterly flow develops through most of the
depth of the troposphere allowing for some nice low level
thermal recovery from our cool Sat/Sat night allowing Sunday to
warm into the mid 80s and lows only dipping into mid 60s.
Monday`s pressure pattern will be poorly defined making for
light winds but overnight high pressure to the north will turn
flow to the north. Forecast soundings show considerable mid level
drying, steep boundary layer lapse rates, and a very shallow
moisture layer at 5-6kt where a few flat cu will reside.
Afternoon temperatures will wind up above climo as they warm
into the mid/upper 80s. A backdoor cold front is due Monday
night.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Temperatures ease back to normal on Tuesday as huge area of
high pressure centered in eastern Canada extends ridge axis
into the Southeast. At the surface this high will come to
dominate our weather for the rest of the period. Mid level flow
on the other hand is a bit more dubious. A strong mid level
ridge also forms over eastern Canada early in the period. It
appears to funnel a shortwave into the Southeast, but now
perhaps not until the end of the period or later. Guidance is
hinting at very isolated showers Wednesday or Thursday ahead of
it. Given the dryness of the wedge isolated coverage may be the
best we can hope for. There will also be a shortwave coming
south down the east side of the Hudson Bay ridge. GFS brings it
all the way into the Carolinas phasing in with the system coming
in from the NW, which seems rather unlikely. Again, given the
dryness of the boundary layer even should it approach it will
have little effect on sensible weather and be more of a bit of a
meteorological oddity.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
MVFR/IFR conditions and strong gusty winds and rainfall from
Ophelia to dominate atleast thru mid morning. Ophelia will
weaken as it tracks further inland and away from Southeast NC
and Northeast SC this afternoon and night. A return to VFR
conditions, generally from south to north, during this
afternoon thru this evening with the low clouds bouncing from
MVFR/IFR categories at times today. Strong and gusty NW winds
will peak this morning, followed by a diminishing trend by late
morning and continuing into tonight. Wind directions becoming
WNW-W this morning will back to W-SW tonight and drop to 5 kt or
less.

Extended Outlook...VFR conditions to dominate Sun and persist
thru early next week as weak high pressure settles in. MVFR
conditions possible by midweek next week as a wedge of high
pressure sets up across the interior Carolinas along with weak
low pressure off the Carolina coasts.

&&

.MARINE...
Through tonight...Tropical Storm Ophelia, moving NNW, progged
to make landfall along the Crystal Coast Of NC early this
morning. The local waters to remain on the western periphery of
this cyclone, resulting in winds backing in direction as the
center passes by just offshore, before pushing inland. Thus
winds peak from the NNW-NW this morning followed by a
diminishing trend late this morning into tonight, with winds
further backing to a W-SW direction. Seas peaking early this
morning, will lose their wind source to build upon and thus
illustrate a rather robust abating trend later today thru
tonight. By daybreak Sun, SW-W winds generally around 10 kt or
less and seas having subsided to 2 to 4 ft, from a peak of 7 to
12 ft early this morning.

Sunday through Wednesday...A weak trough will turn light winds
to southwesterly on Sunday, even if it becomes transient later
in the day. These winds lighten on Monday as the gradient
weakens ahead of a cold front approaching from the north, this
boundary slipping through at night. North to NE winds behind
this boundary on Tuesday as a very large area of high pressure
in eastern Canada extends a ridge axis into the Carolinas. This
anticyclone will remain nearly stationary through the period
keeping our winds out of the NE. They will increase slightly
late in the period as slightly higher pressures sink south out
of Canada. Seas respond slightly not only to the increased
northeasterly flow but also a long fetch NE swell that makes it
into the area along with a lesser SE swell.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
SC...None.
NC...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for AMZ250-
     252.
     Small Craft Advisory until 4 PM EDT this afternoon for AMZ254-
     256.
-- End Changed Discussion --

&&

$$
SYNOPSIS...ILM
UPDATE...IGB
NEAR TERM...DCH
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...DCH
MARINE...DCH/TRA/MBB