Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Newport/Morehead City NC
645 am EST Tuesday Mar 3 2015
a warm front will lift north across the area through tonight. A
cold front will move through Thursday. High pressure will build in
late week into the weekend.
Near term /today/...
as of 645 am Tuesday...surface high pressure centered over the Middle Atlantic
States currently ridging southeast into east NC. Aloft...warm air advection
occurring with strengthening 850mb west-southwest flow. Isentropic lift
associated with increase fgen aloft causing showers to break out to the
west of the area per regional radar imagery. Time of arrival tool
indicates this activity to reach east NC by around 12z and sread
eastward. Should not amount to much and only expecting negligible
quantitative precipitation forecast of a hundredth of an inch or so. Widely scattered showers will
continue off and on through the day as warming aloft continues.
Will see an increase and lowering of the cloud deck as decent inversion
in place today. High temperatures will not be realized until very late in
the day when warm air advection is finally realized at the surface...as the entire
area will be in weak in-situ cad regime with NE to east surface flow
persisting through the day. It will be quite raw...especially inland
where temperatures struggle into the 40s today. By early evening...temperatures
warm into the 50s most areas.
Short term /tonight/...
as of 345 am Tuesday...non-diurnal temperature curve expected tonight as low
temperatures will be realized around 00z...before increase warm air advection on
strengthening low level south-southwest flow causes temperatures/dewpoints to rise
steadily through the night...with most areas around 60 degrees by
daybreak Wednesday. Shower chances will decrease through the night...
and have removed probability of precipitation after around 06z as entire area will be in
warm sector as warm front lifts north of east NC. Cannot rule out
possibility of sea fog for coastal areas as shelf waters are only
in the 30s and 40s...and with rising temperatures and dewpoints through
the night the threat for sea fog development will exist. Will have
to reevaluate and mention possible threat in grids with later
Long term /Wednesday through Monday/...
as of 315 am Tuesday...changeable weather conditions highlight
the first part of the long term forecast period. The upper ridge
over the area Tuesday night slides offshore on Wednesday. Warm
sector airmass becomes firmly entrenched over the area Wednesday in deep
layer SW flow as temperatures warm well into the 70s away from from any
cooling onshore breeze and any sea fog/stratus along the south
facing coastlines. Triggers are lacking for organized precipitation but
could be isolated showers just about anytime of day given any weak
impulse in the moist SW flow.
Most of the precipitation associated with the incoming strong cold front
lines up along and behind the surface boundary. Models continue to trend
later with precipitation arrival from north to south very late Wednesday night
into Thursday. Models also continue to trend a bit warmer as the
precipitation begins to taper off during Thursday afternoon and expect most of
it falls as just a cold rain through much of the afternoon. Still
think that the chances for seeing a brief changeover from liquid
to frozen are good so will leave a chance of sleet and snow in
the forecast before ending by late Wednesday afternoon or evening. It
appears as any accumulation would be minor given the short
duration of any frozen precipitation but a quick burst of heavier snow or
sleet could result in small accumulations. Temperatures remain rather mild
especially over southern areas Wednesday night. Highs on Thursday occur
early then drop rapidly with onset of low level cold air advection during the
A very cold airmass settles in the region Thursday night and Friday. Low
temperatures drop well into the 20s Thursday and Friday nights with highs
Friday struggling to break 40 degrees. A gradual moderation of
temperatures is expected over the weekend and into early next week
as the airmass modifies as the broad eastern trough moves
offshore. Will keep the forecast dry into early next week for now.
Models have been flip floppy with precipitation chances during this time
frame, trying to bring southern stream moisture back up through the
southeast states. Prefer to await better model consistency before
introducing any precipitation into the longer range forecast.
Aviation /11z Tuesday through Saturday/...
short term /through tonight/...
as of 645 am Tuesday...VFR skies early this morning will lower to
MVFR as observed clouds over SC advect into east NC. A warm front
will move through the region bringing lowering clouds and occasional
rain showers to the area through early evening. Have maintained
vcsh mention at all terminals through early evening. MVFR will
lower to IFR and then LIFR in clouds early this evening. Think
that widespread fog will not be an issue due to SW winds overnight
tonight. In addition...low level wind shear will be an issue as a strengthening
wind field just above the surface develops tonight.
Long term /Wednesday through Saturday/...
as of 315 am Tuesday...low level moisture increases Tuesday night
in developing S/SW surface flow and reduced flight categories to
IFR/LIFR in low stratus/fog likely through early Wednesday. Low level
moisture scours out after sunrise Wednesday and expect mainly VFR
by middle to late morning with gusty SW winds throughout the day. A
strong cold front will cross the region from north to south late
Wednesday night and Thursday. Good covering of rain along and behind the boundary
with precipitation diminishing late Thursday...poss mixed with some snow or
sleet inland. Sub VFR conditions are expected again late Wednesday
night and much of Thursday. Strong high pressure builds in for a return
to predominant VFR conditions late in the week and into early next
short term /through tonight/...
as of 645 am Tuesday...NE winds 10 to 15 knots gusting occasional higher
continues this morning as high pressure ridging into the coastal
waters from the northeast. Northeast flow will veer during the day
becoming southerly by late this afternoon and increase to 15-20 knots. South-southwest
winds increase further this evening ahead of strong cold front and
will be in the Small Craft Advisory threshold for the southern and central waters
by 00z...and the northern waters after around 03z. Think that
colder waters over the sounds will prevent the SW wind flow from
making it to the surface initially...keeping winds below criteria here
through the overnight. Another issue will be potential for fog
development over all of the waters as increasing temperatures and
moisture over cold water will produce the threat for fog tonight
into Wednesday. Will have to monitor this potential for an
issuance of a marine dense fog advisory in later forecast updates.
Long term /Wednesday through Saturday/...
as of 315 am Tuesday...strong winds and rough seas will prevail
over the marine area during much of the forecast period as a
strong cold front drops through the waters late Wednesday night into
Thursday. Gusty south-southwest winds continue Wednesday with seas building to 6 to 10
feet outer waters. The cold front will cross the waters late
Wednesday night into Thursday with strong high pressure then building
in from the west Thursday, leading to strong north winds into Friday
which could possibly reach gale force with seas 8 to 12 feet.
Winds/seas will slowly decrease as cold air advection wanes late
Friday with benign conditions now expected on Saturday.
Marine...Small Craft Advisory from 7 PM this evening to 7 PM EST Friday
Small Craft Advisory from 10 PM this evening to 1 PM EST
Friday for amz150.