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000
FXUS62 KILM 220810
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
410 AM EDT Sat Sep 22 2018

.SYNOPSIS...
High pressure will prevail through early next week. A cold
front will approach the coast late Sunday into early Monday,
but no significant rainfall is expected. An upper trough slowly
approaching from the west, will bring a chance of showers in
the upcoming week. A cold front will reach the coast late next
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 355 AM Saturday...Mid level high pressure, although being
slightly suppressed to the southeast in the Atlantic, will
continue to dominate conditions through the near term period. At
the surface, weak high pressure will transition to more of a
weak southwest flow. Overall pops remain at a minimum. Highs
today, following the MET numbers will be in the middle to upper
80s. Sunday morning lows will be in the middle 60s inland to
near 70 along the coast.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 355 AM Saturday...Mid-level and sfc ridging over the
adjacent Atl Waters, will slide a bit further east during this
period. This new positioning will open up a passageway from the
Gulf of Mexico to and across the SE States. And also, another
passageway around the periphery of the upper high/ridge situated
over the western Atl Waters. Models indicate a weak s/w trof or
in this case an Easterly wave, that will track around the
periphery of the upper Atlantic high reaching the ATL Waters
off the Carolina Coasts by the end of this period. The mid and
upper levels will remain quite dry during this period, with
the bulk of the atm moisture residing initially below 850mb.
Moisture does increase in the low levels during this period with
moisture increasing thru 700mb via latest rh model time height
displays and trends for various locations across the FA. This
will lead to additional Cu/SC development and also a slowly
increasing potential for showers and isolated tstorms that may
move onshore especially during the nocturnal phase late Sun
night but more-so for Mon night into Tue and the POPs reflect
this thinking. Temps will run above average with highs 1 to 2
categories above normal and lows around 2 categories above the
norm.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 333 PM Friday...Agreement looks above average in GFS and
ECMWF depictions of the H5 field, in the upcoming work week,
anchoring an upper ridge into the area from offshore through
early next week. The ridge to gradually give way, to impingement
of an upper trough from the west middle to late of next week. As
a vigorous short-wave rounds this trough into Friday, a cold
front will be forced to the coast, where it may stall, or lift
north as a warm front, as the short-wave ejects off to the NE,
leaving the front nearly parallel to the coast. Sensible weather
therefor should see isolated to scattered convection this week,
becoming more unsettled late in the week, mainly by the coast.
Because of ridging and mainly pre-frontal conditions, temps to
run a little bit above normal for late September. Interestingly
enough, the low-level vorticity of Florence this period, looks
to approach our coast as a weak tropical low pressure system
later Tuesday, very weak.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Very weak high pressure, little if any mid or high level
cloudiness to roll across the area and of course plenty of low
level residual moisture is a perfect mix for significant fog.
Expect MVFR to mostly IFR conditions to develop through the
early morning hours. VFR conditions should develop mid morning
and persist through the remainder of the period.

Extended Outlook...Mostly VFR through this period. However,
flight restrictions are possible in late night/early morning
fog/stratus each day. And brief flight restrictions are possible
within showers/thunderstorms Sunday through Tuesday, especially
during the afternoon/evening hours.

&&

.MARINE...
NEAR TERM /THROUGH SATURDAY/...
As of 355 AM Saturday...Weak high pressure will maintain
light winds across the waters through the period. The synoptic
winds will have an east to northeast direction with the sea
breeze shifting winds to southeast this afternoon. Significant
seas will be 1-2 feet.

SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
As of 355 AM Saturday...Elongated surface high off the coast
will gradually retreat east through the period. Gradient will
remain weak with northeast flow peaking on the low side of
the 10 to 15 kt range late in the period. Seas around 2 ft Sat
night into Sun may build to 2 to 3 ft due to prolonged period
of weak northeast flow.

LONG TERM /TUESDAY THROUGH WEDNESDAY/...
As of 333 PM Friday...Increasingly rough this period, because
easterly wind flow is on the increase, persistent. 3-4 foot seas
to become common with 5 ft waves outer waters into mid week,
generally dominant wave periods of 6-8 seconds. Scattered marine
showers and isolated TSTMS can be expected this period. A
tropical low may approach the coast Tuesday night and weaken.

&&

.TIDES/COASTAL FLOODING...
As of 333 PM Friday...Coastal Flood Warnings will be needed for
the  next several days of high tides along the Cape Fear River
at downtown Wilmington as the freshwater flood wave travels down
the river and increasing astronomical tides associated with the
nearing full moon (Sep 24/25) push up the river. Soon after the
full moon the flooding may drop to advisory levels for the days
that follow as both the flood wave and astronomical effects
abate.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...Coastal Flood Warning until 11 AM EDT this morning for NCZ107.
MARINE...None.

&&

$$
SYNOPSIS...MJC
NEAR TERM...SHK
SHORT TERM...DCH
LONG TERM...MJC
AVIATION...SHK
TIDES/COASTAL FLOODING...SHK