Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Newport/Morehead City NC
613 PM EDT Tuesday Mar 31 2015
a cold front will drop south through the region late tonight.
High pressure will build north of the region late Wednesday into
Wednesday night then pass offshore Thursday. A cold front will
approach from the west late Friday and cross the region early
Saturday. High pressure will build in from the northwest Sunday
and move offshore early next week.
Near term /until 6 am Wednesday morning/...
as of 615 PM Tuesday...a surface low will track southeast through
the Middle-Atlantic States and off the Delaware/New Jersey coast this evening
with a cold front moving through eastern NC after midnight
tonight. A strong shortwave will move through the Middle-Atlantic
States and off southern New England overnight...well north of
eastern NC. Limited moisture will be associated with the front thus dry
conds expected. Winds will shift north after midnight behind the
front and may gust upwards of 25 miles per hour along the Outer Banks through
late tonight. Lows tonight will range from the middle to upper 40s.
Short term /6 am Wednesday morning through 6 PM Wednesday/...
as of 215 PM Tuesday....dry and sunny for Wednesday with weak high pressure
building in from north behind the front. Below normal temperatures expected
Wednesday with a cool air mass in place. Temperatures will range from the lower
to middle 60s inland western areas to the 50s across eastern sections.
Long term /Wednesday night through Tuesday/...
as of 345 PM Tuesday...roller coaster temperature ride through
the long term with mainly dry conditions except on Friday night
into Saturday morning associated with a cold frontal passage.
Wednesday night into Thursday...dry period expected with weak high pressure
dominating the weather. Very dry airmass and calm winds/clear
skies Wednesday night allow for excellent radiational cooling. Lows drop
into the middle/upper 30s inland to near 40 coast but think temperatures
should be warm enough to preclude frost mention at this time. Return
southerly flow on Thursday as high shifts off the East Coast and
pleasant afternoon highs in the 70s (60s beaches) with low
Thursday night into Friday...trended dry Thursday night as weak short wave
swings through but no moisture available to work with. Maintained
the slght chance thunder mainly away from the coast on Friday as
moisture return increases and could be weak forcing along sea
breeze front. Main story Friday though will be gusty SW winds
20-25 knots and very warm temperatures as most locales climb into the low
80s inland (upr 60s/low 70s beaches).
Friday night into Sat...forecast thinking remains generally the same with
strong cold front pushing through east NC this period. Warm and
breezy Friday night with lows generally in the low 60s. Minor timing
differences with frontal passage...with 31/12z GFS slightly faster than the
deterministic CMC/ECMWF. Will side with the slightly slower solution
and have highest probability of precipitation very late Friday night into first half of Sat.
Maintained the 50 probability of precipitation with scattered shower/isolated thunder wording due to
convective nature of precipitation. Instability/lapse rates are rather
weak so no severe ts expected though strong southwesterly jet overnight
Friday night will produce isolated thunder embedded in heavier showers.
Quickly drying after around noon Sat with front racing offshore
and skies becoming sunny west to east. Highs should reach the upper
60s/low 70s most areas.
Sat night through early next week...broad high pressure will move
across area at surface with mainly zonal flow aloft. Lows upper 30s/low
40s Sat night with highs near 60 north obx to upper 60s SW zones.
Warming trend early next week as steadily building heights and 850mb
temperatures pushes temperatures back above climatology. It will be mainly dry through
the period...though GFS appears to be suffering from some
convective feedback with fast moving southern stream shortwave
propagating through mean flow on Tuesday. Will keep forecast dry at this time.
Aviation /22z Tuesday through Sunday/...
short term /tonight and Wednesday/...
as of 615 PM Tuesday...VFR conditions will prevail through the
period as high pressure shifts offshore. Southwest winds will be
gusty this evening ahead of a cold front approaching from the
northwest. The front should shift through eastern NC after 06z
Wednesday without impacts on aviation except for a wind shift to
north late tonight. High pressure builds in for Wednesday with northerly winds
gusting to 15 knots after 12z.
Long term /Wednesday night through Sunday/...
as of 345 PM Tuesday...VFR expected to prevail through Friday. Gusty
SW winds 15-25 knots on Friday/Friday night ahead of strong cold front.
Period of sub- VFR conditions likely late Friday night into Sat
morning with scattered showers/isolated thunder ahead of the front. VFR
returning by Sat afternoon with clearing skies. The VFR will
likely last through the beginning of the week.
short term /tonight and Wednesday/...
as of 615 PM Tuesday...based on observation will raise small craft
advisories through 09z for the Albemarle Sound and the adjacent
Alligator river. No other changes planned.
High pressure will shift off the
southeast U.S. Coast this evening with southwest winds throughout.
Low pressure will move east through the Middle-Atlantic States
allowing the SW pressure gradient to increase building winds and
seas to Small Craft Advisory levels. SW winds will be 15-25 knots
over the coastal waters and sounds and overnight. Small Craft Advisory continues for
the coastal waters including the Pamlico Sound. Seas will build to
6 feet for the southern and central outer waters in SW flow...then seas
continue above 6 feet tonight with Post-frontal northerly wind shift for the
central and northern waters through most of Wednesday.
Long term /Wednesday night through Saturday/...
as of 345 PM Tuesday...high pressure building over the waters Wednesday
night will bring tranquil conditions. Winds will become srly and
increase to 15-20 knots Thursday as high moves offshore. Small Craft Advisory conditions
likely again Thursday night into Sat. SW winds 20-30 knots in tightened
pressure gradient ahead of cold front...peaking Friday night/early Sat
morning. The SW winds switch to the northwest and remain gusty first half
of Sat before slowly diminishing. Some minor timing differences in
pushing front through...with GFS slightly faster than the
CMC/European model (ecmwf) global models...though all models indicate the front
being offshore by 18z Saturday. Seas will peak at 8-11 feet late
Friday night/early Sat morning...then slowly subside thereafter.
Marine...Small Craft Advisory until 1 PM EDT Wednesday for amz135-156-
Small Craft Advisory until 5 am EDT Wednesday for amz130-131.
Small Craft Advisory until 7 PM EDT Wednesday for amz152-154.
Small Craft Advisory from 5 am to 3 PM EDT Wednesday for