Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Newport/Morehead City NC
220 am EDT Thursday Apr 2 2015
high pressure will shift offshore today. A cold front will approach
from the west late Friday and cross the region Saturday. High
pressure will build in from the northwest Sunday and move offshore
early next week.
Near term /through today/...
as of 145 am Thursday...surface ridge currently centered over
eastern NC with upper ridging also collocated over the region.
Temperatures have not behaved well late evening/early morning with
coastal plain counties currently experiencing light mixing
preventing excellent radiational cooling despite clear skies and
large scale subsidence. Frost likely occurring along Highway 64 from
Washington County to Mainland Dare County, and nearby Hyde County,
based on limited surface observations of temperatures in the low 30s.
Temperatures have also plummeted for Roanoke Island with Manteo/kmqi
reporting 35 f at 0535z. Will hold off expanding frost advisory
for the Outer Banks of Dare County due to the localized temperature
anomaly of mqi compared to surrounding observation flash Flood Advisory/hse/Oregon Inlet
tide gauge. May not see frost across western and southwestern
zones due to light southeasterly surface flow inhibiting cooling,
but will leave frost advisory in place for now.
The surface ridge will shift offshore today along with the brief
upper ridging flattening out as it slides east. Southerly surface
flow will ensue this morning with light southwesterly flow aloft.
Forecast soundings indicate very dry column today with precipitable waters 0.50
inch or less. High clouds could begin building into the region
from the west by late afternoon. Strong insolation much of the day
with southerly flow will build temperatures into the low 70s inland to
60s along the coast.
Short term /tonight/...
as of 3 PM Wednesday...high pressure will continue offshore tonight with
southerly to south-southwesterly flow persisting across eastern
NC. Weak shortwave will shift over eastern NC after midnight which
may result in increased clouds across the region, but do not
anticipate much impact on sensible weather at this time. Minimum temperatures
will be mild with lows in the middle 50s inland to upper 50s along
Long term /Friday through Wednesday/...
as of 245 PM Wednesday...high pressure will gradually shift
offshore into Friday with a warm southwest flow developing. It
will be quite warm with highs ranging from the lower 80s inland to
lower 70s Outer Banks. With decent instability in place with
surface based lifted indice's around -4 and weak low-level convergence...will
continue small chance of afternoon/evening showers/thunderstorms along any
sea breeze boundary that can develop.
Friday night/Saturday...fairly strong cold front will approach
from the west Friday night...moving offshore by midday Saturday.
Ramp probability of precipitation up to high chance/low likely by early Saturday morning
through around midday...but best instability remains offshore.
After a mild start Saturday morning with lows around 60...maximum
temperatures Saturday only climb a few degrees to the middle 60s...some
15-20 degrees cooler than Friday.
Saturday night/Sunday...strong cool high pressure builds east for
Easter Sunday. Expect rather chilly morning low temperatures
Sunday in the middle 30s inland to middle 40s Outer Banks and with the
axis of the high near the coastal plains Sunday morning...winds
could decouple with some patchy frost well inland. Highs on Sunday
should rebound to the low/middle 60s.
Sunday night/Monday...high pressure moves offshore with southwest
flow again commencing. This will push high temperatures some 5-10
degrees warmer than Sunday with highs middle/upper 60s coast to lower
70s most inland areas. Clouds will increase during the day Monday
given the southerly flow and increased middle-level shortwave energy.
Monday night/Tuesday...with strong low-level warm advection and
deeper moisture advecting into the region...Tuesday will be warm
but increasingly cloudy with a chance of a few showers and
possibly a thunderstorm or two late in the day. High temperatures
will range from the upper 60s Outer Banks to middle 70s inland. Probability of precipitation
remain in the slight chance range for Tuesday.
Tuesday night/Wednesday...a slow-moving cold front will lead to
increased rain chances Wednesday and have probability of precipitation in the high chance
range. Ahead of the front on Wednesday...high temperatures should
reach the lower 70s coast to around 80 inland.
Aviation /06z Thursday through Monday/...
short term /through 06z Friday/...
as of 210 am Thursday...predominant VFR conditions expected through
the taf period. High pressure at the surface and aloft will persist
today through this evening yielding excellent aviation conditions
across eastern NC. May see an increase in upper level moisture
late this evening as next system approaches allowing cirrus to
move into the area from the west.
Long term /Friday through Monday/...
as of 245 PM Wednesday...with a warm southwest flow...there could
be some widely scattered showers/thunderstorms along the sea breeze Friday
afternoon and evening with a brief drop to MVFR conditions. Expect
periods of sub-VFR conditions Friday night and Saturday morning as
showers increase ahead of a cold front. Sunday into Monday with be
VFR as cool high pressure builds into the region from the west.
short term /through tonight/...
as of 220 am Thursday...surface and limited buoy observations
indicate east to southeasterly flow 5-15 knots across the waters,
strongest south as noted by Cape Lookout C-man station and 41037
well off Wrightsville Beach. Seas range 2-3 feet north to 3-5 feet
south, interpolating between buoys off Cape Fear and Duck. High
pressure currently centered over the eastern NC coastal waters
will shift offshore today, aiding in veering winds southeast and
south today, mostly 5-15 knots. Gradient tightens a bit late this
afternoon and overnight for the central coastal waters where 15-20
knots SW winds are expected which will likely produce gusts at or
above 25 kts. Seas diminish to 1-3 feet today as the surface ridge
axis shifts east of the waters. Seas build tonight in response to
increasing southwesterly flow, 3-5 feet this evening with some 6 feet
seas possible for the central waters where gusty winds are more
likely. Will probably need small craft advisories for the central
coastal waters this evening, expanding to larger sections of the
eastern NC coastal waters for Friday as the pressure gradient
tightens further ahead of an approaching cold front.
Long term /Friday through Monday/...
as of 245 PM Wednesday...a period of Small Craft Advisory
winds/seas are possible...starting in the gusty southwest flow
ahead of the front Friday into early Saturday and continuing in
the northwest/north surge behind the front Saturday afternoon
through Saturday night. Winds subside as axis of Cool Ridge of
high pressure builds east across the region Sunday and gradually
shifts offshore Sunday night and Monday.
NC...frost advisory until 8 am EDT this morning for ncz029-044>047-