Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Newport/Morehead City NC
1006 PM EST sun Dec 21 2014
a weak low will develop near the southeast coast tonight then lift
northeast along the North Carolina coast Monday. High pressure
builds into the area from the north Monday night and Tuesday. A
strong cold front will approach from the west Tuesday night and
cross the region on Wednesday. High pressure builds to the south of
the area through the end of the week. Another cold front will
approach the area next weekend.
Near term /until 6 am Monday morning/...
as of 10 PM sun...forecast in good shape. No changes needed for
overnight. Mostly cloudy skies and cool conditions prevail across
east NC. High pressure ridging down the eastern Seaboard bringing weak
cold air advection and keeping temperatures in the 40s area wide. Overnight...low/mid
level fgen will increase from south to north as 850mb flow becomes
southerly and increase warm air advection aloft enhances precipitation and lowering ceilings.
This being driven by a coastal trough that will begin to take
place overnight. It will take a little bit longer for northern areas to
saturate per current dewpoints in the low 30s and have held off
likely probability of precipitation until after midnight. Lows will drop down to the upper
30s inland to with middle 40s coast.
Short term /6 am Monday morning through 6 PM Monday/...
as of 315 PM sun...light rain will be ongoing in the morning hours
across the area as area of lift continues in the low and middle levels.
Frontal inversion will actually strengthen through the day as
warming aloft will continue despite persistent northerly flow at the
surface. This will be a good setup for areas of drizzle through the
afternoon despite accumulating rain moving off to the north of the
area. It will be a raw cool day inland with the low clouds and
drizzle with highs struggling into the 40s...though coastal trough
moving up the NC coast will allow areas to the south and
east...particularly downeast Carteret and the obx...to possibly rise
to around 60 degrees or higher as flow becomes south or southeast
for a time Monday afternoon.
Long term /Monday night through Sunday/...
an active and wet weather pattern is expected across the area
through middle week as a series of weather systems in quick succession
impact the region.
Insitu damming occurs Monday night and expect damp conditions to
prevail as widespread low clouds and patchy drizzle are favored in
this type of pattern. Have trended toward cooler NAM temperature
forecasts given its generally better performance in these surface wedge
patterns. Expect the in situ damming will be slow to erode Tuesday
so again have favored the lower temperature guidance. Rain will
begin to overspread the area late Tuesday into Tuesday evening from
the SW as an active warm front lifts north across the area. Expect a
non diurnal temperature curve as lows occur early Tuesday night and
rising late as the warm sector establishes over the area. Precipitation
chances will remain high late Tuesday night through Wednesday and it
now appears the rain will not exit until Wednesday evening inland,
perhaps lingering into Thursday morning immediate coast. Will
continue mention of thunder all areas as still expecting to see a
high shear/Low Cape setup as strong upper jet sets up amid backed
low level flow. If any instability is realized this could mean a
small chance of strong to severe storms...with the main threats
damaging wind gusts or an isolated tornado.
Temperatures will be quite warm Wednesday reaching into the 70s away from
cooling onshore flow Wednesday afternoon. Winds will be quite gusty on
Wednesday and nearing Wind Advisory criteria for coastal counties as
the southerly flow strengthens.
For Thursday through Saturday...expect high pressure to build
across the region from the southwest producing dry and cooler
conditions for Christmas day. It will still be gusty in a tight
westerly gradient Thursday. Temperatures will be near climatology behind the
front for Christmas day and Thursday night as upper trough moves off the
East Coast. Low level thickness values support highs warming into
the low 60s Friday and Saturday but a bit cooler near the beaches.
Another cold front will be approaching from the west Saturday but
model timing and system strength differences limit long range
forecast details at this time.
Aviation /03z Monday through Friday/...
short term /through Sunday evening/...
as of 10 PM Sunday...ceilings will lower throughout the overnight
as moisture increases through the column. Ceilings will drop from
VFR to IFR within a few hours. Coastal taf sites will drop to
LIFR by sunrise. Rain will also continue to overspread the region
overnight. Expect a damp and dreary day Monday as the surface low
moves up the Carolina coast. Winds will be out of the north
through the period.
Long term /Monday through Thursday/...
IFR conditions look to continue Monday evening given insitu damming
with surface high pressure to the north. Poor flying conditions may linger
into Tuesday as the surface winds will be weak and tough to scour
out remaining low level moisture. More widespread precipitation
develops late Tuesday and Tuesday evening which will likely produce
intervals of sub VFR conditions. A warm front lifts through the area
late Tuesday night/early Wednesday but low levels remain near saturation
so any improvement in flying conditions may be short-lived,
especially with increasing rain chances again ahead of a cold front
Wednesday into Wednesday evening. Winds will be quite gusty out of
the south ahead of the front on Wednesday...then switching to west
and gusty Wednesday night and Thursday. Dry high pressure and predominate
VFR returns to the area behind the cold front late Wednesday night through
short term /through Monday/...
as of 10 PM sun...NE windscontinue over all of the waters late
this evening. A coastal trough will sharpen off the Carolina coast
overnight while weak low pressure rides up along the NC coast Monday.
Ahead of it...east to NE winds will strengthen this evening...then
back to the east and southeast on Monday across the waters as the low moves
along the coast. Think that winds and seas will reach marginal Small Craft Advisory
criteria first across the southern/central waters tonight...then
translating across the northern waters on Monday. Have therefore
hoisted a Small Craft Advisory through Monday for the coastal waters...ending
across the south in the morning.
Long term /Monday night through Thursday/...
lighter winds and 2 to 4 feet seas are expected Monday night and
Tuesday as high pressure briefly builds over the waters. A strong
cold front approaches Tuesday night and crosses the waters late
Wednesday night into early Thursday. Winds will become south and
increase rapidly late Tuesday night and Wednesday before becoming
westerly Wednesday evening. Seas respond by building and peaking at
6-12 feet Wednesday...and continued previous seas forecast per Swan as
wavewatch seems underdone. The models continue to suggest that
low end gales in gusts will be possible Wednesday.
Marine...Small Craft Advisory from 7 am to 4 PM EST Monday for amz152-
Small Craft Advisory until 10 am EST Monday for amz156-158.