FXUS62 KILM 180732
Area Forecast Discussion
National Weather Service Wilmington NC
232 AM EST Mon Dec 18 2017
Mild air will surge into the region Monday and Tuesday ahead of
a low pressure system that will approach from the west. This
system will bring moderate rain Wednesday and Wednesday night.
High pressure will build in Thursday and then weaken on Friday
as a cold front slowly approaches from the west.
.NEAR TERM /THROUGH TONIGHT/...
As of 3 AM Monday...A diffuse warm air advection pattern will
continue across the area through the near term. The mid level
flow will be mostly west to southwest until late tonight when a
slight shortwave moves across. This will be critical as it will
switch the wind direction to offshore. As for today there is
little in the way of forcing and most guidance keeps pops to the
south of the area and thus I have walked back the inherited
values. Mostly cloudy skies will continue across the area.
Guidance has been insistent on sea fog developing on the better
defined southwest flow the aforementioned trough develops. I
have added this to the forecast for late this afternoon and
through the evening hours until the weak offshore flow develops.
I did undercut guidance for temperatures today via the moisture
laden conditions. On a similar note I increased values for
Tuesday morning lows.
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 3 AM Monday...A mild and dry Tuesday will give way to a
wet and chillier Wednesday as a frontal system emerging from the
deep south impacts the area. Temperatures on Tuesday will be
elevated above normal as a bubble high north of a dissipating
frontal system brings a relatively warm SWly flow to the region.
Highs will be mainly in the upper 60s most places. Deep-layer
moisture increases overnight as an upper short wave drives a
developing frontal system east across the Carolinas. Extensive
cloud cover and good rain chances will keep highs topped in the
lower to mid 60s Wednesday. POPs will be likely on Wednesday and
Wednesday night, with rain likely tapering off by daybreak on
Thursday as the frontal system slides south of the area.
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 3 PM Sunday...A front could bring a healthy dose of rain
high as pressure wedges in from the north on Thursday. This
wedge will weaken but largely remain in the Carolinas, allowing
for a moderation towards warmer temperatures. It then lifts out
by Saturday clearing the path for warm and moist advection ahead
of the next cold front, previously slated for arrival Saturday
but it now appears to be up to two days slower.
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
As of 06Z...Not the best of aviation conditions for this cycle
as a moisture laden atmosphere with little forcing will be in
place. The big concern is sea fog which the guidance has been
pointing to the past several cycles across the coastal
terminals. This will develop late this afternoon and this
evening. I have prevailing IFR conditions to address. Until then
ceilings drop to MVFR across most areas.
Extended Outlook... Unsettled weather Monday through Thursday
morning as a near stationary front moves in and out of the region.
NEAR TERM /THROUGH TONIGHT/...
As of 3 AM Monday....Weak wind fields will continue across the
coastal waters through the period. However a better defined
southwest flow will develop during the day which will be a
change from the erratic nature of the wind direction from the
past day or so. Speeds remain ten knots or below. By early
Tuesday a weak surface trough passing by will switch the winds
to an offshore component. Sea fog is expected to develop late
this afternoon and impact all waters to some degree until the
wind shift occurs. Overall seas will be 1-2 feet with perhaps a
few three footers late.
SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 3 AM Monday...A slack pressure gradient will bring benign
conditions to the waters into the daylight hours of Wednesday
with winds of around 10 kts and seas of right around 2 ft. A
frontal system slowly sliding south across the waters will bring
periods of rain to the coastal waters on Wednesday. Conditions
deteriorate Wednesday night in the wake of this system with NE
winds picking up to 20 kts or more and seas building up to 6 ft
in places. A Small Craft Advisory may be required for Wednesday
LONG TERM /THURSDAY THROUGH FRIDAY/...
As of 3 PM Sunday...With a front stalled over the area but at
an uncertain latitude there is some uncertainty related to
Wednesday's wind forecast. There is also some uncertainty
regarding wind speed. For now though the current solution
favored keeps the front to our north and allows an approaching
wave to ramp up wind speeds later in the day Wednesday. Once
this low moves by high pressure will nose in from the north and
turn winds decidedly NE. A short-lived advisory is tough to
rule out either ahead or behind this system, or both given the
aforementioned uncertainties. As the high weakens heading into
Friday looking for decreasing and veering winds.
Back to Main Forecast Discussion Page