Area Forecast Discussion
Issued by NWS Wilmington, NC-- Remove Highlighting --
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FXUS62 KILM 030238
Area Forecast Discussion
National Weather Service Wilmington NC
938 PM EST Fri Dec 2 2016
High pressure will be reinforced from the northwest and as a
result the weather will remain dry and cool through early
Sunday. The high will move offshore Sunday night. A strong and
complex low pressure system will likely bring good soaking
rains to the forecast area early to mid next week. A strong
cold front late next week will usher in the coldest and driest
air of this late Autumn season thus far.
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
As of 915 PM Friday...The sfc trof, or one could even call
it a reinforcing cold front, drops south across the ILM CWA
from late this evening thru and during the pre-dawn Sat hours.
This can be seen with the latest RAP model using its progged sfc
pressure pattern and 1000-850mb thickness fields respectively.
Around midnight, the RAP 1000-850mb thickness fields range from
1325 northern portions to 1342 southern portions of the ILM CWA.
By daybreak Sat, the 1000-850mb thickness fields drop to 1312
north portions and 1330 south portions of the ILM CWA. The FA
will get some decent CAA and slightly lower sfc dewpoints but
will be short-lived, ending by midday Sat. Only clouds for
tonight will be mainly thin Cirrus given upstream trends and
various model rh time height displays across the FA thru Sat
morning. Have only lightly massaged the latest min temp fcst
and the hourly sfc temps and dewpoints. Mainly as a result of
the sfc winds decoupling prior to the sfc trof passage later
tonight. This a result of the decent rad cooling conditions and
winds having decoupled ahead of the sfc trof.
As of 215 PM Friday...Dry, zonal flow across the Eastern United
States will continue through the remainder of the afternoon and
tonight. The bulk of the column will remain dry however some
cirrus will potentially overspread the area overnight as a
storm system across the Southwest United States begins to
direct some moisture toward the Carolinas. Scattered cirrus and
just enough wind will likely hinder optimal radiational cooling
tonight, nevertheless the typical cool spots may dip into the
lower to mid 30s.
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
As of 215 PM Friday...The atmosphere will be in transition
during the short term period as high pressure loses its
influence to a developing coastal front and approaching
southern stream system. As a result, rain chances will be on
the rise, especially by Sunday night given the proximity of the
coastal front and increasing isentropic lift. Followed a blend
of MAV/MET numbers for the highs/lows each period, however
expect non-diurnal temp trends along the coast Sunday night with
the coastal front moving onshore late.
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM Friday...Very active weather slated for the long
term with some minor uncertainties yet to be hashed out.
Monday`s weather will be quite unsettled with high pressure to
our north being overrun by moderately strong warm advection.
Rainfall should initially be light to moderate as there is
little deep layer forcing and all of the resulting upglide will
be confined to the lower levels. Rainfall rates increase heading
into Tuesday as height fall and PVA deepen the ascent. The
interplay between two surface lows may dictate temperatures and
their positions are not agreed upon superbly between various
guidance. Drying should be rapid Tuesday night as this
conglomerate system lifts northward. Wednesday and Thursday will
feature a series of moisture-deprived cool fronts moving
through from the northwest. The latest front Thursday night will
usher in some true Arctic air.
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...VFR is expected for this 24 hour TAF valid period.
Winds of 3-8 kt, highest at the coastal terminals, will veer
from W- NW to NNW-NNE overnight. No significant clouds
expected. After sunrise winds speed will increase to 8-12 kt.
High clouds will be on the increase with mid level clouds moving
in from the west late in the day.
Extended Outlook...VFR. Moderate confidence for MVFR/TEMPO
IFR late Sun into Mon. Highest confidence of IFR is Mon night
NEAR TERM /THROUGH TONIGHT/...
As of 930 PM Friday...SCEC for the ILM NC waters remains in
The winds and seas have been tweaked to take into the account
of the passage of a sfc trof or weak cold front, dropping from
south to north late this evening and into the overnight hrs.
After its passage, winds will veer to the NW-NNW at 15 to
possibly 20 kt across the ILM NC Waters, and NNW to NNE at 10-15
kt and possibly up to 20 kt.
Significant seas initially will have an influence from a weak
SE 1 to 1.5 foot, 8 second period ground swell. After the
passage of the sfc trof, locally produced 3 to 5 second period
wind waves will become dominate.
As of 215 PM Friday...Surface high pressure will continue to
build across the waters from the W-NW through tonight. A minor
surge will build south across the waters generally after
midnight. The increase in northerly winds as a result of the
surge will allow for a period of Small Craft Should Exercise
Caution conditions primarily for the NC waters which will carry
into the short term period. Along the Cape Fear waters seas are
expected to build to 4-5 ft, especially away from the inshore
waters given the orientation of the fetch.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 215 PM Friday...Northerly winds will diminish during
Saturday afternoon as high pressure builds eastward. The high
will slowly progress off the Mid-Atlantic coast by Sunday night
allowing the flow to veer to a northeasterly direction beginning
late Saturday night. A coastal front will become better
established by Sunday night and as it lifts northward the wind
is expected to sharply veer to a southerly direction late in the
period. Seas of 4 to 5 ft Saturday morning off the Cape Fear
coast will subside during the afternoon. Seas should remain
below 3 feet during Sunday then begin to build again Sunday
LONG TERM /MONDAY THROUGH WEDNESDAY/...
As OF 3 PM Friday... Winds will be light on Monday but the
wind direction is uncertain. High pressure to our north will be
eroding along the coast as a coastal warm front develops ahead
of low pressure developing over the Gulf. By Tuesday the winds
should swing to the south and ramp up to where wind or seas will
necessitate Small Craft Advisory. Wind turns offshore by
Wednesday and decreases as dual-barreled high pressure lifts out
to the north.