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000
FXUS61 KAKQ 181756
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
156 PM EDT Wed Sep 18 2019

.SYNOPSIS...
Surface high pressure builds into the region from the north
tonight through Thursday, and then settles over the region
Friday. Meanwhile, Hurricane Humberto is forecast to track well
east of the Carolina coast today and Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 155 PM EDT Wednesday...

Latest analysis reveals ~1028mb high pressure centered over e
QB/ northern New England this aftn, and is ridging swd into the
VA Piedmont. Meanwhile, Hurricane Humberto continues to track
ENE about 200 mi west of Bermuda. Compressed pressure gradient
between surface high building ridging south into the region, as
Humberto continues to move away from the coast is resulting in
some breezy conditions, especially along the coast. Coastal
sites continue to gust to 25-30 mph, with occasional gusts to
~20 mph even inland.

Mostly clear and cool tonight, with low temperatures ranging
from the low 50s from the Piedmont to the MD Ern Shore to the
upper 50s/around 60F over coastal SE VA/NE NC.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 150 PM EDT Wednesday...

Surface high pressure continues to build swd along the coast
tonight into Thursday, and builds overhead into Friday. Continued
breezy Thursday although the wind should not be quite as high
as Wednesday, as gradient slackens with Humberto farther
offshore. Partly cloudy again along the coast with SCT late
morning and aftn CU, and mostly sunny inland. Pleasant with high
temperatures generally 70-75F, with upper 60s for the MD
Atlantic coast. Clear sky, light wind will bring the coolest
night of the period Thursday night. did nudge inherited minima
down a degree or two per latest guidance, but no major changes
necessary. Early morning lows Fri morning in the u40s/l50s
inland...m/u 50s along the coast.

High pressure will be over the SE coastal plain on Friday,
bringing a modest warm-up. but still dry/pleasant. Highs in the
mid to upper 70s, low to mid 70s along the coast.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 135 PM EDT Wednesday...

Temperatures will moderate back near to above normal over the
weekend into early next week, as sfc high pressure slides
offshore. Aloft, the region will remain on the periphery of an
upper level ridge of high pressure, which will rebuild over the
region from the southwest during the upcoming weekend.

Above average temperatures likely prevail through this period
with highs in the mid/upper 80s to around 90 degrees with early
morning lows generally in the 60s area wide.

Rain chances remain essentially nil through the first half of
the period, and don`t go much higher even with the next front
early next week. Aforementioned upper ridge holds strong over
the southeast, and keeps moisture from next (weak) front...and
any remnant moisture from TC Imelda...well north of the local
area late Monday and Tuesday. Pops are no better than slight
chance over far northern CWA Mon night and Tue...and silent
(<14%) central and south through the period. Temperatures look
to remain at or above climo normal next week.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
As of 130 PM EDT Wednesday...

Latest analysis reveals 1028+mb sfc high pressure centered over
e QB/nrn New England at 18z, and was building into the Mid
Atlantic as Hurricane Humberto tracked ENE well off the coast.

Onshore flow continues ~12-15kt with gusts to 20-25kt for
coastal terminals, and 8-12kt farther inland. SCT-BKN CU moving
onshore from the Atlantic coast and will linger over terminals
this aftn, gradually scouring out this evening. Mostly clear
tonight with an 8-12kt NE wind along the coast, and light out of
the NE farther inland.

Outlook: Dry conditions are expected Thursday through Monday as
high pressure slides across the region Thursday and Friday, and
then offshore over the weekend into early next week.

&&

.MARINE...
As of 350 AM EDT Wednesday...

Early this morning, Hurricane Humberto was continuing to move ENE
several hundred miles off the SC coast while ~1026 mb high pressure
was centered over far nrn New England/srn Quebec. Humberto is
forecast to slowly transition into an extratropical cyclone during
the next couple of days as it interacts with a frontal system. The
pressure gradient between Humberto and the high is leading to NE
winds of 15-20 kt N/20-25 kt S of the VA-NC border. Waves are ~2 ft
across the northern Bay and 3-4 ft across the south. Seas have
increased to 5-6 ft N/6-9 ft S.

High pressure builds SSW toward central VA/NC today and tonight as
Humberto continues to track to the ENE. Even though Humberto will
continue to slowly move away from the Atlantic coast, the pressure
gradient between Humberto and the aforementioned high will increase.
Therefore, expect a slight uptick in winds before peaking during the
00z-06z (Thu) timeframe. Sustained winds will increase to 20-25 kt
on the Ches Bay/23-27 kt on the ocean by 00z Thu. At least a few
gusts to ~30 kt are likely on the Lower Ches Bay, srn coastal
waters, and the Currituck Sound this aftn through the first part of
tonight. Occasional gusts to ~20 kt are likely on the upper rivers
later today-06z Thu. A few gusts to 25 kt are possible on the lower
part of the York River, so went ahead and issued an SCA from 1 PM
today-1 AM Thu. Not sure that 20 kt gusts will be frequent enough to
warrant SCAs for the Rappahannock/Upper James, so left these two
zones out of any headlines attm. Seas build to 7-8 ft N/8-10 ft S by
late this evening. Will maintain the High Surf Advisory for VA
Beach/Ern Currituck (through 7 PM Thu). SCAs remain in effect
through 7 AM Thu for the Ches Bay, Lower James River, and Currituck
Sound. The SCA for the ocean is now in effect through 7 AM Fri (due
to very high confidence in seas remaining aoa 5 ft).

On Thursday, the high is expected to build SSW toward the area, and
Humberto will be far enough offshore to allow the pressure gradient
to relax some. As a result, NE winds slowly diminish from early Thu
AM through the day on Thu. The current forecast has wind gusts
dropping below SCA thresholds by early Thu afternoon. The high is
expected to settle into the region from Fri-Sat before moving to the
SE of the area by Sun. Winds turn to the N then NW on Fri before
becoming SW by early Sat AM. Sustained winds will remain aob 12 kt
from Fri through the weekend. However, seas (and waves near the
mouth of the Bay) will be slow to diminish. SCAs may need to be
extended for the mouth of the Ches Bay through Fri AM/ocean through
Sat (due to waves/seas) in future forecast packages.

&&

.TIDES/COASTAL FLOODING...
As of 12 Noon EDT Wednesday...

Added CF Advy for Hampton/Norfolk for Money Point/Sewells Pt
reaching low-end minor thresholds with upcoming tide cycle this
aftn. Additional nuisance to low minor levels possible late
tonight and again tomorrow.

As of 530 AM EDT Wednesday...

Tidal anomalies have risen to 1-1.5 ft above normal in areas
adjacent to the Ches Bay/rivers. Nuisance to minor tidal
flooding is expected in areas from the Lower MD Ern Shore to the
srn shore of the Ches Bay/upper James River during today`s high
tide. Therefore, Coastal Flood Statements/Advisories have been
issued accordingly. With the persistent NE wind, tidal
anomalies will remain elevated/slowly rise through Thursday. As
a result, additional Statements/Advisories will be needed for
both tonight and Thursday`s high tide cycles. At this time, it
looks like any tidal flooding from today-Thu will mainly be
minor. However, water levels may come very close to moderate
flood thresholds at Bishop`s Head, Lewisetta, and Jamestown
during the high tide cycle Thu aftn. Tidal anomalies slowly fall
from Thu night-Fri as winds continue to diminish. However,
lingering nuisance to (low-end) minor tidal flooding is possible
through Fri.

The current forecast keeps water levels just below minor flood
thresholds along the Atlantic coast of MD, VA, and NC. However,
there is a very slight chc that water levels exceed minor flood
thresholds on the oceanside of the VA Ern Shore/NC during the
higher astronomical tides today/Thu.

A high rip current risk is forecast for today, and will likely
continue into Thursday, as swell from Humberto propagates toward
the coast.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...High Surf Advisory until 7 PM EDT Thursday for NCZ102.
VA...Coastal Flood Advisory until 8 PM EDT this evening for VAZ075-
     077-078-089-090-093-095>097-524-525.
     High Surf Advisory until 7 PM EDT Thursday for VAZ098.
MARINE...Small Craft Advisory until 7 AM EDT Friday for ANZ650-652-654-
     656-658.
     Small Craft Advisory until 7 AM EDT Thursday for ANZ630>634-
     638.
     Small Craft Advisory until 1 AM EDT Thursday for ANZ636.

&&

$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...AJZ/MAM
LONG TERM...MAM
AVIATION...AJZ/MAM
MARINE...ERI
TIDES/COASTAL FLOODING...