Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Newport/Morehead City NC
1255 am EDT Wednesday Jul 30 2014
high pressure will build over the area through Thursday...as a
frontal boundary remains stationary over the offshore waters. The
front will drift back toward the coast late week into the
weekend with unsettled weather pattern returning.
Near term /overnight/...
as of 1255 am Wednesday...no sig changes to forecast for update...tweaked
grids slightly to reflect current trends. Showers have ended and
expect the area to be pred dry overnight. Patchy fog will be
possible overnight but at this time not expecting enough coverage
to include in grids. Lows in the lower 60s to lower 70s...with
light NE/southeast flow.
Short term /Wednesday/...
as of 2 PM...high pressure dominates the weather with a relatively
dry air mass in place...precipitable waters below 1.25. No probability of precipitation forecast.
Comfortable temperatures with middle 80s and partly cloudy skies.
Long term /Wednesday night through Tuesday/...
as of 330 PM Tuesday...an unseasonably deep longwave upper trough
will continue over the eastern Continental U.S. Through the middle to late week
period. Meanwhile...surface high pressure to the west will ridge into the
region through Thursday with a frontal boundary stalled offshore with
light northerly flow bringing unseasonably low dewpoints across the
region. Precipitable waters remain below 1.25" (less than 25 percentile for this
time of year)...coverage will be minimal and will keep probability of precipitation
below 10 percent. Temperatures will be comfortable with lows in the low
to middle 60s inland to around 70 coast and highs in the middle 80s to
low 80s obx.
The long wave trough begins to gradually Delaware-amplify late in the
week while the offshore trough migrates westward towards the
coast setting the stage for a prolonged period of unsettled
weather across eastern NC this weekend into early next week. The
region will reside in the favorable right entrance of the upper
jet with surface convergence increasing along the coastal trough as
well as precipitable waters increasing to above 2". Timing differences among
models have grown in respect to the trough moving into the region
with the NAM and GFS trending slower...moving the trough inland
late Friday/Friday evening versus the European model (ecmwf) which moves the trough in
late Thursday night. Similarly...the GFS is slower with the Delaware-
amplification of the upper trough late in the weekend into early
next week. With the uncertainty in timing of these features as
well as potential embedded shortwave disturbances moving through
flow aloft decided to cap probability of precipitation in the high chance range for the
latter half of the long term with this package.
Aviation /06z Wednesday through Sunday/...
short term /through tonight/...
as of 1255 am Wednesday...VFR currently with scattered-broken middle clouds. Main
challenge for forecast overnight will be the potential for patchy fog.
Will continue MVFR visibilities in tafs...with better chances at
iso/oaj/pgv. Any fog that develops should burn off shortly after
sunrise with pred VFR returning.
Long term /Thursday through Sunday/...
as of 330 PM Tuesday...high pressure building in from the west will bring
good flying weather through Thursday with VFR conditions
dominating. Cannot rule out patchy early morning fog at the
terminals each morning but with an unseasonably dry airmass in
place conditions are not conducive for widespread fog development.
A trough of low pressure moves back into the region Friday through
the weekend putting east NC in favorable regime for widespread
showers and thunderstorms and periods of sub VFR conditions will
short term /through Wednesday/...
as of 1255 am Wednesday...latest observation show east/NE flow across the waters
5-15kt north of Hatteras and 10-20kt south...with seas 2-4ft. Gradient
will continue to tighten slightly through the night between front
lingering offshore and high pressure building to the west
increasing speeds slightly to 15 knots tonight through Wednesday.
Long term /Wednesday night through Sunday/...
as of 330 PM Tuesday...high pressure ridges in from the west through Thursday
with a stalled frontal boundary east of the waters. Winds will
predominately be east at or below 15 knots with seas around 2 to 4 feet. The
front retreats westward as a coastal trough Friday...the European model (ecmwf)
continues to be faster bringing the trough into the region early
Friday morning while the American models continue to be
slower...bring the trough inland Friday evening. Winds become southerly
after the trough moves through and remain below 15 knots with seas
continuing around 2 to 4 feet.