Scientific Forecaster Discussion
fxus62 kmhx 121710
Area forecast discussion
National Weather Service Newport/Morehead City NC
1210 PM EST Thu Dec 12 2019
high pressure will continue to ridge in from the north through
Friday morning. Then, an area of low pressure will form and move
up the East Coast late Friday, bringing a cold front through the
area on Saturday. High pressure will build in briefly Sunday
and Monday, followed by another cold front on Tuesday.
Near term /until 6 PM this evening/...
as of 945 am Thursday...other than some stratocumulus skirting
the Outer Banks, associated with a developing trough offshore,
skies are clear across eastern NC at mid-morning. Strong cold air advection is
underway and temperatures are unlikely to climb more than a few
degrees through late afternoon with highs in the upper 40s to
lower 50s in most locations. Latest 3km NAM and hrrr continue to
indicate some isolated showers along the Outer Banks and sounds
region later in the day and will maintain the low pop for these
areas for this update.
Short term /6 PM this evening through 6 am Friday/...
as of 630 am thurs...precip chances will continue tonight for
the Outer Banks and areas just to the west as the coastal trough
moves closer to land. Showers will also increase from the west
towards daybreak as an area of low pressure develops to the SW.
Temperatures will likely bottom out early tonight, and then rise
through the rest of the night as low level thicknesses and
clouds increase. We'll see lows in the mid 30s inland, while
areas along the coast only drop into the mid to upper 40s early
tonight. By tomorrow morning, temps will have risen into the low
40s inland, and the low to mid 50s along the coast.
Long term /Friday through Thursday/...
as of 330 am Thu...periods of unsettled weather expected
through the long term period, with roller coaster temps as a
progressive/amplified active weather pattern is expected to
Friday through Saturday...rain chances inc Fri as deep srly
flow increases with digging long wave trough across the lower MS
River Valley, which will spur low pressure development over the
deep south. This low will ride up the coast rapidly, with rain
becoming likely through the day Fri, peaking Fri evening when
best upward vertical velocity/fgen/pwats will converge. Maintained the categorical
pops this period, as good model to model consistency as well as
spaghetti ensembles converging on this solution. Widespread
moderate to heavy rain will be possible Fri evening. Still some
uncertainty on exact track of the low, there could be potential
for strong to even severe storms if storm track is further
inland such as advertised by the ecm/CMC. Latest 12/00z ecm
continues to indicate aoa 500 j/kg of sfc based CAPES advecting
into the area with plentiful shear overnight Friday. Best chance
of a stronger storm would be along the coast where best
instability will reside. Upr trough will still be west of the
region though deepest moisture will be offshore Sat morning.
Could be quite a bit of showers around first half of Sat due to
good forcing with upr trough and continued swrly flow sfc and
aloft, and have a likely pop through around noon, with rapid
drying later in the day. It will be mild both days with highs
in the 60s.
Sunday through Monday...drier conditions with near to above normal
temps expected late weekend to early next week as quasi zonal
flow develops and progressive high pressure dominates.
Tuesday...next potent cold front and possible low pressure
system quickly advance towards the region by Mon night and Tue,
and introduced 50-70% pops this period, focused on Tue as
converging model solns focus timing of the next strong cold
front moving through by later Tue.
Wednesday...a return to dry albeit cooler weather pattern by Wed
as long wave trough axis shifts to the eastern Seaboard with sfc
high pres building into the region. Highs in the 50s with lows
dropping back to the 30s.
Aviation /18z Thursday through Tuesday/...
short term /through Friday/...
as of 1210 PM Thu...VFR conditions currently across the area
with mostly sunny skies. Pred VFR expected through 06z tonight,
with prolonged period of sub-VFR conditions developing late
tonight and early Fri morning. Will likely see ceilings lower to
MVFR between 06-12z, with shower chances increasing after 15z
Friday. Could see a period of low level wind shear develop Friday afternoon and
evening as strong SW winds develop aloft.
Long term /Friday night through Tuesday/...
as of 330 am Thu...sub-VFR conditions expected into Sat morning
with widespread rain showers and low clouds. Return to VFR
later Sat through Monday as high pres builds back in.
short term /through tonight/...
as of 945 am Thursday...winds have diminish below 20 knots and
have dropped all sca's for the sounds on this update. North/north-northeast
winds continue at 20-25 knots with gusts as high as 31 knots at
Diamond buoy and 30 knots at Cape Lookout at mid- morning. Seas
persist in the 5-8 foot range. A coastal trough will form over
the western Gulf Stream this afternoon, which will have strong
winds continuing just to the west of it, especially over the
central and southern waters. Winds eventually subside to NE
15-20 tonight with seas 5-6 ft.
Long term /Friday through Monday/...
as of 330 am Thu...no changes to previous thinking with an
active weather pattern expected through the weekend which will
result in hazardous boating conditions with strong winds and
elevated seas at or above 6 ft through the period. There will be a break
in the gusty winds and high for much of Friday ahead of the
next system, and seas may drop below 6 feet for all but the ctrl
waters, but winds and seas come back up Friday night ahead of
low pressure that will skirt up the coast bringing gusty swrly
winds 15-25 kt through Sat. Winds and seas finally subside later
Sunday as high pres begins to build into the area.
Marine...Small Craft Advisory until 10 PM EST this evening for amz135.
Small Craft Advisory until 7 PM EST Sunday for amz152-154-156-
Small Craft Advisory until 1 am EST Friday for amz150.