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000
FXUS62 KILM 162330
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
630 PM EST Wed Jan 16 2019

.SYNOPSIS...
Cold high pressure will move offshore Thursday while weak low
pressure on its heels brings a few showers early Friday. Strong
low pressure passing west and north of the area this weekend
will bring warming, and a good chance of rain Sunday as a cold
front crosses the coast. Cold air will return early next week
as Canadian high pressure dives into the Carolinas.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 300 PM Wednesday...Elongated ridge axis offshore overnight
will  be absorbed by second, larger area of high pressure
extending south from the Great Lakes region. Gradient will
remain weak with light to calm surface winds overnight. FLow
just above the surface will be from the southwest, which will
lead to a slight increase in low level moisture. Fog may become
an issue early Thu due to good radiational cooling and the
slight bump in moisture. Weak warm advection will lead to a
slight bump in lows overnight with temps ranging from upper 20s
to mid 30s.

Larger high pressure centered to the north shifts east on Thu, with
low-level flow becoming southerly during the day. Gradient remains
light, keeping flow weak, but there will be a definite shift to a
warm advection regime tomorrow. Weak shortwave and resulting surface
low emerging from the central Plains will lift northeast, across the
KY and OH Valleys during the day. Associated cold front approaches
from the west late in the day, accompanied by increasing moisture.
Moisture will still be lacking however. Forecast soundings keep
precipitable water well below 1 inch through tomorrow evening and
subsidence layer around 800 mb will be tough to overcome. At this
point do not anticipate much in the way of showers through the end
of the period and will keep precip chances under 20% through Thu.
Highs will be near to slightly above climo on the back of increasing
warm advection, mid to upper 50s.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 352 PM Wednesday...Massive vortex around northern Ontario
will help propel a short-wave ripple in the H5 flow across the
coast late Thursday night. A brief period exists Thursday
evening where enhanced column moisture and convergence could
bring showers, with little measurable rainfall expectation.
The system carries little cold air advection and overall the
system does not disrupt a warming trend, but may delay it a bit
as a weak cold front briefly dips across SE NC on Friday.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 352 PM Wednesday...Warming temperature trend prevails
this weekend, bringing maximums well into the 60s, about 10
degrees above mid January normals. Pre-frontal, warm air
advection Saturday will transition into frontal passage Sunday,
in morning and off the coast in early afternoon. Will retain
slight chance of a TSTM Sunday because the low-level convergence
and dynamical support aloft should work in concert, and for what
it may contribute, near maximum diurnal warmth in FROPA closer
to the coast. In question remains available instability.
Frigid air invades again as Canadian high pressure swoops into
the Carolinas. As the cold high approaches, we probably should
expect widespread 20s next Tuesday morning, isolated teens.

&&

.AVIATION /00Z WEDNESDAY THROUGH MONDAY/...
As of 00Z...Looking back to this morning, the fog was worse than the
models were implying. Cold soil temps may have been the contributing
factor. For this reason have gone with IFR fog inland, and to a
lesser extent along the coast. Thursday, any fog will mix out on or
just after 13Z with light and variable winds becoming south to
southeast aft 18Z.  High clouds will will be on the increase aft
18Z but VFR conditions will continue.

Extended Outlook...Mainly VFR until Saturday and into Sunday when
MVFR conditions are possible in showers Saturday and due to CIGS
Sunday. VFR Monday.

&&

.MARINE...
NEAR TERM /THROUGH THURSDAY/...
As of 300 PM Wednesday...High pressure over the waters tonight
will be absorbed by larger high centered over the Great Lake
early Thu. Gradient will remain weak into Thu afternoon, keeping
speeds 10 kt or less. Direction will initially be from the
north but as the high to the north shifts east, Thu afternoon,
southerly flow will develop. Period ends with south to southwest
flow over the waters, however speeds will remain under 10 kt.
Seas will remain 2 ft or less through the period with an east-
southeast swell being dominant.

Short TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 352 PM Wednesday...A cold front late Thursday night will
bring winds from SW to W into Friday but no advisories expected
as winds remain 15 kt with a few gusts up to 20 kt. Showers late
Thursday night may enhance gusts locally, briefly. Because winds
will be mainly offshore and swell has faded, wave heights will
remain low this period.

LONG TERM /SATURDAY THROUGH MONDAY/...
As of 352 PM Wednesday...Worsening marine conditions can be
expected beginning late in the day as a strong cold front
approaches the waters, and SE winds mount to 20-25 knots
Saturday night. As balmy gulf stream air encounters cool inshore
waters, we may see sea fog late Saturday into Sunday along with
rough and hazardous wave action. By Sunday S-SSW waves of 4-8 ft
every 8-9 seconds will dominate waters. SW-W winds Sunday will
turn to NW Sunday night as cold air dives in, and advisories
flags will continue.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.

&&

$$

SYNOPSIS...8
NEAR TERM...III
SHORT TERM...Colby
LONG TERM...MJC
AVIATION...31