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Area forecast discussion 
National Weather Service Wilmington NC
1030 am EDT Fri Oct 21 2016

mild weather will prevail through today before chillier air behind a
cold front comes crashing into the eastern Carolinas Friday night.
The weekend will be characterized by seasonably cool temperatures
with lows in the 40s and highs remaining below 70 degrees Saturday
and Sunday. A brief warm-up Monday will be followed by a reinforcing
shot of dry and cool air Monday night. This will set the stage for
dry and fair conditions in the upcoming week with temperatures near
normal for the season.


Near term /through tonight/...
as of 1030 am Friday... fog has shown some impressive persistence
along a narrow strip from eastern Bladen and Columbus into far
western Brunswick counties but has elsewhere burned off. Satellite
imagery shows rapid erosion developing in the aforementioned areas,
which will soon join others in full sunshine. Strong cold front just
west of Charlotte and bearing down on the coastal plain. Any shower
activity will be pretty limited but 12z guidance is in fact showing
isolated activity developing later this afternoon. Changes to the
forecast were very minor, generally just showing a later timeframe.
Even our diurnal curve looks OK, in its early afternoon Max followed
by falling temperatures as the strong cold air advection kicks in.


Short term /Saturday through Sunday night/...
as of 330 am Friday...the new change in the upper longwave
pattern affecting the the ilm County Warning Area this period will be upper
troffing affecting the eastern U.S. Basically from the Great Lakes
eastward. And, upper ridging across the western 2/3rds of the
U.S. The mean upper trof axis will lie just off the East Coast of
the U.S. No embedded mid-level S/W trofs are expected to affect
the ilm County Warning Area this period. With this pattern, pcpn chances will be
null and void. For Saturday, at the sfc, the forecast area will be under
continued gusty northwest winds that will slowly abate during the aftn
and evening. With the center of high pressure progged to drop to
the Gulf Coast states for Sunday, winds will not totally drop out
but will subside from what transpired during the day on Saturday.
Sky conditions thru the period will be clear any cloud that makes
it across the Appalachians will scour out quickly under northwest
downslope trajectory flow. For now will use a blend of the
available model data for Max/min temps thruout this period. Not
entirely bought on any 1 MOS guidance given the change in airmass.


Long term /Monday through Thursday/...
as of 300 am Friday...a rebound in temps into the mid 70s for
early in the week in light west-SW flow will be knocked back down
once again as a dry cold front drops south through Mon aftn. This
boundary is barely evident when looking at pcp water field as the
values rise from around a half inch up to .75 inch right along it.
Do not expect any pcp with this front. North-northwest will follow as high
pressure builds in behind it, but ridging in the upper atmosphere
and bright October sunshine will offset the cooling to produce
temps around 70 most places. High pressure will shift off the East
Coast on thurs with a west-SW return flow allowing temps to warm once
again. Overall dry weather with plenty of sunshine through the


Aviation /12z Friday through Tuesday/...
as of 12z...with the exception of VFR at kilm, MVFR/IFR/LIFR
prevails across the this morning as areas of dense fog continue.
Expect conditions to improve within the next few hours as
westerly winds increase to around 5 kts. Through the rest of
today, a strong cold front will propagate west to east across the
area, bringing vcsh and westerly winds around 10 to 12 kts with
gusts near 20 kts, becoming northerly behind the front. Overnight,
light northwesterly winds and nearly clear skies are expected.

Extended outlook...expect VFR.


near term /through tonight/...

As of 1030 am Friday...quite a bit going on in the very near
term...that is the early part of the period. Light west winds will
veer to the SW ahead of strong cold front this afternoon and then
back to northwest this evening with a strong increase in wind speeds as the
cold air pours in. No real changes to the overall forecast thinking
or timing so the previous discussion has been left:

As of 600 am Friday...Small Craft Advisory has been raised for the SC waters starting
by the mid afternoon and for the NC waters by early evening.

The story for mariners will be initially the easterly swell
affecting the local waters from the low now roughly located about
420 miles southeast of Cape Fear. Weak showers rotating around
this low could reach the local waters from the east this morning
before drying up. This low is progged to turn NE, hooking up or in
this case getting absorbed with the strong cold front, well
northeast of the local waters, in association with the
progressive mid-level S/W trof.

The main story for mariners will be the passage of the strong cold
front late this afternoon or early evening followed by the tightened
sfc pg which will last across the local waters thru tonight. With
excellent cold air advection after the cfp, this will combine with the tightened
sfc pg to produce strong Small Craft Advisory conditions with possible gale force
wind gusts especially off Cape Fear or Cape Romain. Significant
seas will build late this afternoon and tonight due to building
wind driven waves.

The easterly swell from the exiting low will continue to affect the
local waters tonight which may boost seas a little higher than what
guidance is dictating.

Short term /Saturday through Sunday night/...
as of 330 am Friday...winds are expected to remain active thruout
this fcst period. The highest northwest winds are slated early Saturday
due to the tightened sfc pg and continued or reinforcing cold air advection
across the local waters. The center of the sfc hi drops to the
Gulf Coast states Saturday night and remains in this position into
Monday. The sfc pg does slightly relax in addition to neutral
advection. Thus winds will peak Sat and lower to below Small Craft Advisory
thresholds by sunset Saturday for all waters. Winds will slightly
lower further on Sunday thru Sunday night backing to a more
westerly direction around 15 kt. Significant seas will peak early
Saturday then slowly drop off as the easterly swell from the
exiting low decays. Wind driven waves will become the main and
dominant producer of sig. Seas thruout this fcst period. Should
see a nice range of seas Saturday thru Saturday evening then
become more uniform during Sunday into Sunday night.

Long term /Monday through Tuesday/...
as of 300 am Friday...light west-SW winds early Monday will veer to
the northwest as a dry cold front moves across the waters Mon aftn.
Another surge of cool air as high pressure builds down from the
north behind front. Expect winds to kick up out of the north-northwest from 15
to at least 20 knots Monday night shifting to the north-NE by tues as
high pressure migrates east as it extends down from Canada. Wna
showing seas remaining below Small Craft Advisory thresholds running 2 to 3 ft
ahead of front early Mon and then jacked back up to 4 to 5 ft Mon
night into tues in gusty northerly winds.


Tides/coastal flooding...
as of 615 am Friday...looks like between the hours of noon and 5
PM for the next chance for the lower Cape Fear River to spill out
of it's banks. At this point, it could breach the moderate
flooding thresholds of 6.7 ft MLLW as forecast and observed at the
downtown Wilmington gage. Expect the next advisory or warning to
be issued within the next 3 to 4 hours. The following are high
tides for the gage on the lower Cape Fear River of downtown
Wilmington thru Sunday...

High tide 2:57 PM on Fri.
High tide 3:23 am on Sat.
High tide 3:56 PM on Sat.
High tide 4:22 am on sun.
High tide 4:53 PM on sun.


as of 300 am Friday...the ASOS at the Lumberton, NC Airport
(klbt) has no power and the emergency generator which had
maintained power since Hurricane Matthew has run out of fuel. Lbt
is awaiting a fresh supply of fuel so the equipment can be up and
running again.

Observations and climate data from Lumberton will remain missing
until further notice.


Ilm watches/warnings/advisories...
Marine...Small Craft Advisory from 5 PM this afternoon to 5 PM EDT
Saturday for amz254-256.
Small Craft Advisory from 5 PM this afternoon to 9 PM EDT
Saturday for amz250-252.



near term...mbb
short term...dch
long term...rgz
tides/coastal flooding...dch

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