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Area forecast discussion 
National Weather Service Newport/Morehead City NC
244 PM EDT Fri Sep 30 2016

an upper level low will remain quasi-stationary across the Ohio
River valley tonight then move north Saturday and northeast
towards New England Sunday pushing a cold front across the area
Sunday night. The front will stall off of the coast early next
week while high pressure builds in from the north. Hurricane
Matthew is forecast to move north of the Bahamas and off the
southeast coast mid to late next week. Please see the latest
forecasts from the National Hurricane Center for the latest on
Hurricane Matthew.


Near term /through tonight/...
as of 215 PM Friday...scattered showers with embedded thunderstorms
continue to move north over eastern NC this afternoon. Latest
infrared/WV imagery indicates another shortwave located off Myrtle Beach
SC approaching from the south in deep layer S/south-southwest flow over the
region. Minor adjustments for the pops/wx this afternoon/evening
to account for latest trends, though latest high-res guidance does
not appear to be handling the shortwave approaching from the south
and thus expanded 40-50 pops back into the western zones through
00-01z. May need to maintain higher pops far inland if shower
coverage increases or another shortwave lifts north through the
area. Precipitable water values remain high for late September, ~1.5-1.8 inches)
thus a small threat for flooding will remain, mainly for low lying
and poor drainage areas. Better chances for shower and
thunderstorms will shift more east for late tonight.

The vertically stacked low pressure system centered over the
central Ohio River valley will remain mostly stationary tonight
but may begin to move northeasterly late. Meanwhile a weak surface
low resides across the western Carolina Piedmont with a stationary
front extending east across eastern NC, currently located along
the Albemarle Sound and slowly lifting north, with a cold front
extending south across offshore SC and the southeast coast.

MOS and forecast soundings suggest a period of fog overnight,
mainly along and west of Highway 17. Boundary layer moisture will
remain high with winds becoming light and perhaps decoupling for a
few hours late tonight. Overnight low temperatures will range from
the mid 60s inland to low/mid 70s along the coast/obx.


Short term /Saturday/...
as of 225 PM Friday...the upper low over the Ohio River valley will
slowly drift north towards the southern Great Lakes on Saturday.
The weak surface low across western NC will lift north into Virginia/Maryland
with the trailing cold front moving into the area. The deeper
moisture will continue to shift to the coast and offshore during
the day Saturday. Continued diminishing trend for pop across
inland counties but maintained chance pops with thunderstorms east
of Highway 17. Shortwaves embedded within the mean S/south-southwest flow aloft
will be the primary drivers for convection. Severe potential
remains low but cannot rule out an isolated strong to severe
thunderstorms with biggest threats of damaging wind gusts and
hail. Heavy rain threat shifts more towards the coast, in line
with best moisture flow shifting more eastward. Max temperatures
will be a degree or two warmer than today, with highs in the low
to mid 80s across eastern NC.


Long term /Saturday night through Thursday/...
as of 315 am Friday...
Saturday...the quasi-stationary upper low will begin to move
north Saturday but still produce a deep cyclonic flow across the
area. The surface cold front will remain just to the west with
continued moist/unstable southerly flow ahead of it across the
region especially along the coast. Will continue chc pops coast
tapering to slight chc deep inland. Will remain warm with srly
flow producing highs in the low to poss mid 80s.

Sunday through the upper low begins to lift NE Sunday
the sfc low/front slowly dissipates as it approaches sun and
drifts off the coast and stalls Mon. Models cont to keep better
moisture along and east of the coast so cont low chc pops CST
Sunday tapering to slight chc Monday...inland areas will be mainly
dry. Not much change to temps with lows cont in the 60s inland to
low 70s CST with highs upr 70s to lower 80s.

Tuesday through Wednesday...high pres will gradually build in
from the north Tue and slide east Wed. This will keep most areas dry Tue
with small pop CST. On Wed increasing onshore flow will lead to a
little better chc of showers across the region. Little cooler with
more pronounced north-northeast flow Tue and Wed with highs mainly 70s to poss
around 80 S.

Thursday and Friday...forecast will be dependent on track of
Hurricane Matthew. Will increase rain chances especially coast and
keep cool high temps in the 70s in NE flow. Please see the latest
forecasts from the National Hurricane Center for the latest on
Hurricane Matthew.


Aviation /18z Friday through Wednesday/...
short term /through Saturday/...
as of 2 PM Friday...VFR/MVFR conditions expected through 03-05z
due to scattered showers and thunderstorms which may yield brief
periods of sub-VFR conditions. Better showers chances will reside
across coastal sections tonight. Could see areas of fog develop
again tonight with abundant low level moisture and light winds
persisting. Dry air filtering in from the west and only a marginal
signal in forecast soundings would argue against fog development.
For now, will side with persistence and the fact that precip was
observed across all taf sites today, with more possible this
afternoon/evening. Confidence in IFR fog occurrence is low due to
these factors. Any fog should mix out after sunrise Saturday with
mostly VFR conditions expected as a cold front slowly slides into
the region from the west.

Long term /Saturday through Tuesday/...
as of 315 am Friday...scattered shra and a few tsra cont Sat with
a period of sub VFR conditions possible. Drier air will work in
from the west Sunday into Tuesday with decreasing chc of shra and
mainly VFR...there will be threat of some late night and early
morning fog and stratus with light winds this weekend into early
next week.


short term /through Saturday/...
as of 240 PM Friday...latest surface and buoy data indicate southeast/east-southeast
winds 10-15 kt across the waters. The weak boundary bisecting the
waters has lifted closer to the Albemarle Sound this afternoon,
and should continue to shift north overnight. A weak cold front
continues to approach the waters from the west. Expect to see
winds become S 10-15 kt across all waters this evening through
tonight as the pressure gradient tightens some ahead of the cold
front. Wavewatch and nwps a bit underdone with seas across the
northern waters as it does not seem to have been capturing
stronger winds/swells off the mid-Atlantic coast over the past
day or so and buoys off Duck and Oregon Inlet reporting seas
5-6 feet. No change to current Small Craft Advisory for the waters
north of Cape Hatteras through this afternoon since buoys 44095
and 44014 continue to bounce between 6-7 ft. Seas are expected to
subside to around 3-5 feet later this evening and tonight. South of
Hatteras seas are expected to remain around 2 to 4 feet through
Saturday coincided with slightly stronger southerly flow.

The cold front will continue to move east towards the coast on
Saturday. Winds will remain southerly around 10 kt with seas
mostly 2-4 ft. Showers and thunderstorms will again be possible.

Long term /Saturday through Tuesday/...
as of 315 am Friday...weak low pres/cold front west of the region
Sat will lead to mainly S flow aob 15 kts. The low/front will
slowly slide east toward the coast Sunday then move offshore by
Monday. Light mostly S winds Sunday will become NE Mon but remain
weak. The NE/east flow is forecast to increase to 10 to 15 knots Monday
and 15 to 20 knots Tuesday. Seas thru the period will be mainly 2 to
4 feet through Monday then increase to 3 to 5 feet Tuesday.


Mhx watches/warnings/advisories...
Marine...Small Craft Advisory for hazardous seas until 6 PM EDT this
evening for amz150-152.


near term...dag
short term...dag
long term...rf/jme

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