nc discuss
Office: ILM
FXUS62 KILM 211515
AFDILM
Area Forecast Discussion
National Weather Service Wilmington NC
1015 AM EST Wed Nov 21 2018
.SYNOPSIS...
Clear and cool weather will prevail through Thanksgiving. A
freeze is possible for some inland locations Friday morning.
Rain will overspread the region Saturday, as a Gulf system
tracks up the coast. This system will clear out Sunday with
a warming trend into early next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 930 AM Wednesday...Not a cloud in the sky this morning as
expected and temperature trends are on track. No changes needed
with the morning update. Previous discussion follows:
Plenty of cool and dry air making its way
into the area this morning as high pressure builds in from the
west. The northerly flow will back slightly this afternoon
before getting knocked back to the N-NE as high pressure begins
to build down from Canada. This will produce a reinforcing shot
of cool and dry air with gusty northerly winds. Overall expect
plenty of sunshine today with temps just shy of 60 most places
and then quite a chill to wake up to Thanksgiving morning with
gusty northerly winds making temps in the mid 30s feel as if
they are less than 30 around daybreak Thurs morning.
Frost should be minimal or non existent tonight. There is a bit
of dewpoint recovery later this aftn into this evening, and the
atmosphere decouples, allowing temps to drop out, but once that
high begins to build down from the north, winds will actually
kick up again towards midnight in CAA overnight.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 4 AM Wednesday..."Chilled sunshine Thanksgiving" might be
one way to describe Thursday, with daytime highs running 5-8 deg
F below normal for the day. This brought to you by a northern
stream anticyclone that supplants decaying zonal high, nosing
aggressively southward alee of the Appalachians into Carolina
country, producing a strong pressure wedge late Thursday and
Friday. Bright skies to greet early Friday, will transition
to grey hues by late day, as an emerging Gulf system introduces
strong SFC-8K theta-e advection and a canopy of high clouds
invading skies. By daybreak Saturday, rain chances elevated
into the 'likely' category and heading upward. The low track
will impact rain character, but with a strong wedge in place,
will maintain 'rain' as primary, as the low-level stability is
running to high for TSTMS as this time.
Have outdoor tasks early Thanksgiving? Look for temperatures at
daybreak 35-39 degrees, low 40s near the beaches, warming into
the middle 50s into afternoon.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 300 PM Tuesday...The main feature in the extended period
will be the storm system developing across the lower Mississippi
Valley moving across our area Saturday. Overall the system
doesn't look quite as amplified as earlier versions hence the
QPF fields are a little more disorganized. Still pops remain
high for Friday night into Saturday and I did incrementally
increase values to address a little more certainty. A quick
moving secondary system, that once looked like quite the
rainmaker for our area is now very progressive in nature and
will bring a cold front quickly through the area with slight to
low chance pops early nest week. Overall temperatures remain
above climatology for most of the period but the late front
Monday seems to usher in the coldest airmass of the season just
beyond this forecast period.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
As of 12Z...High confidence for VFR conditions through the forecast
period. High pressure will keep skies clear through this evening.
Another reinforcing shot of cold air will arrive tonight, which will
bump up the winds to near 10 kts. Northeast winds on Thursday, with
below normal temps.
Extended Outlook...VFR to prevail next couple of days. Storm
system Friday night into Saturday could bring rain and
potential IFR/MVFR conditions to the region. VFR Sunday and Monday.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 930 AM Wednesday...SCEC headline has expired and
conditions match this trend. Expect this lull in winds and seas
to be short lived with more robust conditions arriving early
Thursday. Previous discussion follows:
Borderline precautionary conditions early
this morning as high pressure builds in from the west behind
cold front. Decided to go with exercise caution headline up
through 9 am. Northerly winds up to 15 to 20 kts will produce
occasional gusts to 25 kts, but will diminish heading into this
afternoon as winds back slightly to the N-NW. Seas basically
running 3 to 4 ft with 5 fters confined to the outer waters this
morning.
Heading into tonight, high pressure will begin to build down
from Canada with a reinforcing shot of cold air and tightening
gradient. Expect a surge in northerly winds and seas after
midnight and running into Thursday. Winds should reach 15 to 20
kts with seas increasing toward daybreak Thursday.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 4 AM Wednesday...Treacherous marine period as strong NE
winds get only stronger, as high pressure noses southward
aggressively into the inland Carolinas, tightening the local
marine environment pressure gradient. Steep wind-waves with
dominant wave periods of 4-6 seconds, and 4-8 foot heights will
produce dangerously steep waves, and breakers offshore at time
in wind-sea wave phasing Thursday night and Friday. Thanksgiving
is not a good day for a family joy ride offshore, as winds will
be on the uptick, with gusts of 20 to 25 kt.
LONG TERM /SATURDAY THROUGH SUNDAY/...
As of 3 PM Tuesday...Lower confidence in regards to winds early
in the period as models are erratic showing a closed low here
and there as the mid level forcing for a decent storm system
wavers. I basically maintained the overall trend of northeast
winds early, transitioning to southeast then finally west to
northwest as the system exits the area late in the weekend. Seas
could eclipse small craft criteria early with a lingering fetch
from the northeast then the decent flow with the passing storm
system. Some relief is expected with the offshore flow later in
the period.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...08
NEAR TERM...RGZ/SHK
SHORT TERM...MJC
LONG TERM...SHK
AVIATION...DL
Office: MHX
FXUS62 KMHX 211659
AFDMHX
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1159 AM EST Wed Nov 21 2018
.SYNOPSIS...
High pressure will build into the region today. A dry cold front
will push through the area tonight with strong high pressure
building back into the region Thursday and Friday. The next storm
system will affect the region Friday night into Saturday followed
by a cold front on Monday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 940 AM Wed...High pressure continues to ridge in from the
west at the surface below a broad upper trough across the
eastern CONUS. Light N/NW winds will continue, and with this
downslope flow direction, expect almost a cloudless day. High
temps will reach the mid to upper 50s, and will approach 60
along the southern coast.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
As of 215 AM Wednesday...A dry backdoor cold front will push
through the area tonight with strong high pressure building in
from the north late. Model soundings show the column remaining
very dry with PW values remaining below a half inch and will
likely see very little clouds associated with the front. CAA
ramps up after midnight with a northerly surge developing. Lows
expected in the mid 30s inland to upper 30s to lower 40s closer
to the coast. There should be enough mixing to prevent frost
development except possibly well sheltered locations.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
As of 3 AM Wednesday...Quiet and cool weather is expected for
Thanksgiving and Friday, before a strong storm system brings
widespread rain and wind Saturday. Another cold front will bring
more rain for early next week.
Thursday through Friday...A large 1038 MB high over the Great
Lakes will control our weather Thursday, making for a great
travel day Thanksgiving Day albeit chilly. Daytime highs will
hold in the 40s inland, or about 15 to 20 degrees below normal
for late November. With such cool daytime highs and a clear sky
expected Thursday night, a widespread hard freeze is expected
inland with lows in the upper 20s. We still have a decent
pressure gradient through the night with the high to our north
but if we are able to decouple as MAV/MET guidance suggests, a
few mid 20s are a good possibility in our normally colder spots.
AS the high mentioned above slides off the coast Friday the
return flow will boost temps back well into the 50s with some
showers possible over the coastal waters.
Friday night through Saturday night...A mid-level trough will
become negatively tilted by Friday night as a surface low moves
offshore during the day Saturday. The 0Z Euro and Canadian
remain the most aggressive in bringing widespread rain over our
area with the surface low track either over eastern North
Carolina or just offshore. The GFS is much stronger, but now
well offshore, with the main upper level support splitting to
our north and south, with a lower threat for heavier rains.
Little adjustments made to the forecast for this period as we
continue to mention a 80%+ chance for rain with periods of
moderate rain possible. With a flow off the ocean it will be
much milder with temps well into the 60s, especially near the
coast. Good model confidence that the system will be a fast
mover so we took out chances of rain after midnight Saturday
night.
Sunday through Monday...A closed mid-level low will move well
north of the region late in the weekend. This will drag a cold
front across the region. This will produce scattered showers and
continued with a 30-40 percent PoPs for late Sunday night into
Monday. Temperatures will remain mild with highs well into the
60s both day.
Tuesday...Cool Canadian high pressure will build into the region
behind the front on Tuesday, with highs temperatures some 10
degrees cooler than Monday with dry conditions expected.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Short Term /through 18Z Thursday/...
As of 1200 PM Wednesday...Clear skies across the region with
high pressure anchored off the northern NC coast at midday.
Expect clear skies and light W/NW winds this afternoon. A weak
back door front will cross the CWA overnight with winds veering
to more northerly and increasing a bit after midnight. This
should preclude any fog formation tonight as VFR conditions
should prevail through this TAF cycle.
Long Term /Thursday through Sunday/...
As of 315 AM Wednesday...VFR conditions are expected into
Friday with high pressure over the area. Sub-VFR conditions are
expected Friday night into Saturday as a developing low moves
across the area. VFR conditions should return for Sunday.
&&
.MARINE...
Short Term /through tonight/...
As of 230 AM Wednesday...High pressure will build in from the
west today with N/NE winds around 10-20 kt early this morning
diminishes to 5-15 kt while backing to W/NW through the day.
Seas around 3-5 ft early will subside to 2-3 ft this afternoon.
A backdoor cold front will push through the area tonight with a
strong northerly surge around 15-25 kt with higher gusts
developing after midnight. Seas will build accordingly to
around 4-6 ft northern waters and 2-4 ft southern waters toward
daybreak Thursday. Will initiate a SCA for all waters but the
inland rivers starting at 08z tonight.
Long Term /Thursday through Sunday/...
As of 315 AM Wednesday...The surge of stronger winds will
continue over the coastal waters Thursday, with north winds
gusting to 30 kts, with seas building toward 8 feet the outer
waters. Winds veer gradually toward the east Friday and while
winds remain elevated, will gradually subside closer to 20 kts.
Seas mainly 4 to 5 feet by Friday afternoon.
After a brief lull over the waters, a new area of low pressure
will move up the coast Saturday. Ahead of this southeast winds
will produce small craft conditions as early as midnight Friday
night, with gale conditions possible by midday Saturday
especially the outer waters as winds gust toward 35 kts out of
the southeast with waves building toward 10 feet. With the
departure of the low Saturday night winds switch into the
northwest and diminish quickly Sunday to less than 20 kts but
seas will remain above 6 feet with small craft conditions
continuing over the outer waters.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...Small Craft Advisory from 3 AM Thursday to 6 AM EST Friday for
AMZ135.
Small Craft Advisory from 3 AM to 2 PM EST Thursday for AMZ130-
131.
Small Craft Advisory from 3 AM Thursday to 6 PM EST Friday for
AMZ152-154.
Small Craft Advisory from 3 AM Thursday to noon EST Friday for
AMZ150-156-158.
&&
$$
SYNOPSIS...SK
NEAR TERM...SGK
SHORT TERM...SK
LONG TERM...EH
AVIATION...CTC/SK
MARINE...EH/SK
Office: RAH
FXUS62 KRAH 211734
AFDRAH
Area Forecast Discussion
National Weather Service Raleigh NC
1235 PM EST Wed Nov 21 2018
.SYNOPSIS...
High pressure will build in from the west today, bringing
chillier weather to the region. A dry backdoor cold front will push
into North Carolina early Thursday, bringing colder temperatures. A
storm system will bring a chance of rain Saturday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 950 AM Wednesday...
Just minor adjustment required to the near term forecast, mainly in
the hourly temperatures this afternoon.
The 12Z upper air analysis depict a fairly deep westerly flow over
the Carolinas as broad high pressure was located over the southern
Gulf and an upper trough resided over the Great Lakes into New
England. This weather pattern will maintain dry conditions and
seasonal temperatures across our region. Based on 14Z temperatures,
a mean wly flow and a dry air mass (precip water value at GSO this
morning 0.20 inches) should permit temperatures to rebound into the
50s, and close to 60 across the far south. ~WSS
Tonight, the potent upper level low will pull east of the Hudson Bay
with a strong high pressure moving over New England. This strong
high pressure will continue to push southeast allowing the pressure
gradient across North Carolina to increase. This increased gradient
will allow the area from decoupling keeping low temperatures
slightly warmer than the previous night, but still in the mid to
upper 30s. ~Haines
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 315 AM Wednesday...
Thursday morning, the high will push far enough east and be
strong enough (~1036 MB) to allow the strong front to dive south
and then southwest and into central North Carolina by the
afternoon. By late Thursday evening the front will have cleared
the zones with temperatures quickly falling. During the day as
the front moves through the area (from NE to SW) no
precipitation is expected just cloud cover (from moisture
trapped behind the frontal inversion).
Thursday night, temperatures will quickly fall off (esp the
northeastern zones where skies are expected to be clear). The
low level moisture in association with the front looks to be
confined near the Piedmont as the front runs into the mountains.
Lows Thursday night will likely be in the mid to upper 20s with
the coolest temperatures towards the northern zones.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 350 AM Wednesday...
The flow aloft across the CONUS during the medium range will be
characterized by progressive and amplified nrn stream flow,
accompanied by a strong/energetic srn branch jet from the sern
Pacific to the sern US - a pattern of lower than average
predictability, in part to stream interaction and consequences.
Despite that forecast uncertainty, the overall forecast rationale
remains unchanged. Within this energetic pattern, a couple of low
pressure systems are forecast to affect the ern US - the first a
Miller A coastal low track Sat, and the second into the Great Lakes,
with secondary triple point development in the lee of the srn and
cntl Appalachians and ensuing more rapid deepening off the middle
Atlantic and Northeast coast Sun-Mon.
Arctic surface high pressure will be migrating off the nrn middle
Atlantic coast, and ridging swwd in damming fashion in the lee of
the Appalachians. Associated chilly nely flow, and dryness
characterized by surface dewpoints in the teens to around 20
degrees, will accompany the dry air ridge on Fri. With partly to
mostly sunny conditions, particularly through early afternoon,
temperatures will rebound from a very cold morning, into the mid-upr
40s, to lwr 50s from MEB to FAY, CTZ, and GSB.
The high will move offshore in the aforementioned progressive flow
aloft, such that an in-situ damming regime will develop over the srn
middle Atlantic states as warm, moist advection returns atop the
surface ridge Fri night-Sat, in response to the approach of a
negatively-tilted trough aloft from the mid MS valley to the middle
Atlantic states. Wet-bulbing of the dry air ridge will cause
temperatures to evaporatively cool into the mid 30s to low 40s, as
rain becomes widespread late Fri night-Sat. Rainfall amounts from
around one half to one inch are expected - a downward adjustment
from previous expectations.
Lingering in-situ damming, low clouds, and patchy light rain or
drizzle may continue into Sun, ahead of the next system scheduled to
affect cntl NC Sun night-Mon - likely too quickly to allow for
adequate moisture return to yield more than a period of showers with
another tenth of an inch or two.
Nrn stream troughing centered over the Great Lakes/Hudson
Bay/Northeast, with dry, wly flow at trough base across the
Carolinas, will yield dry and cooling conditions - from a breezy Mon
with temperatures in the mid 50s-mid 60s, to upr 40s to mid 50s on
Tue.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
As of 1235 PM Wednesday...
There is a high probability of VFR persisting across central NC
through Thursday afternoon. Surface winds through 09Z Thu will be
mainly westerly at less than 10kts. A cold front will drop southward
across central NC very early Thu morning, veering the sfc winds to a
north northeast direction and increasing to close to 10kts. After
14Z Thu, a few places will experience gusts 15-18kts. A few patches
of stratocu will filter into the northern counties Thu morning with
bases 1800-2500 FT AGL expected though coverage should be no more
than two-tenths coverage.
VFR parameters appear likely through Friday evening. An approaching
area of low pressure will increase moisture and lift over central
NC, leading to a solid chance for MVFR/IFR ceilings and MVFR
visibility Saturday through Saturday evening. The low pressure
system will depart Saturday night, improving aviation conditions
west-to-east. VFR parameters anticipated late Saturday night through
Monday.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Haines
NEAR TERM...WSS/Haines
SHORT TERM...Haines
LONG TERM...MWS
AVIATION...WSS
