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000
FXUS61 KAKQ 160201
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
1001 PM EDT Mon Oct 15 2018

.SYNOPSIS...
A cold front crosses the area overnight, then stalls over the
Carolinas on Tuesday. An area of low pressure moves along the
front Tuesday night, with high pressure building back in from
the north later Wednesday and Wednesday night.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 955 PM EDT Monday...

Latest analysis reveals surface high pressure is located well
offshore of the Southeast coast this evening, with low pressure
over southern QC and a trailing cold front extending south
across the coastal northeast into western portions of VA into
the western Carolinas. Still very mild ahead of the front this
evening with pre-frontal temperatures still well in the 60s to
low 70s at 02z.

No major change to forecast rationale overnight. Front will drop
across the area late, with some scattered showers to drop SE
across the MD Ern Shore overnight, reaching SE VA/NE NC toward
morning. The best forcing remains N of the area, but there
should still be enough low-level convergence and lift for
showers to spread across mainly the ern third of the area.
Moisture will be limited with QPF less than 0.25". Wind gusts to
20 mph will follow the front overnight...with a few gusts to
~25-30 kt possible with the frontal passage over coastal
sections.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
As of 400 PM EDT Monday...

The initial shortwave trough is forecast to move offshore early
in the morning, with 30-40% PoPs for showers across SE VA/NE
NC, and ~20% from central VA to the MD Ern Shore. By aftn, PoPs
are forecast to be ~20% for srn VA/NE NC and <15% across the N.
Mostly cloudy to overcast across the srn half of the area
Tuesday, and generally mostly cloudy N, although partial
clearing is possible across the MD Ern Shore. The cold front is
expected to move through NE NC by mid-morning, and then stall
across NC by aftn. Temperatures area expected to range from the
mid 50s N to mid 60s S to begin the day, and then only rise to
the upper 50/around 60F N, and remain steady, or even drop a few
degrees in the aftn across the S (especially NE NC). Another
shortwave trough and area of weak low pressure tracks along the
front late Tuesday night into early Wednesday morning. This will
bring additional rain to SE VA/NE NC where PoPs are ~60% and
bordered by 30-40% from the SW Piedmont to the VA Ern Shore, and
aob 20% farther N. Lows Tuesday night range from the mid 40s
NW, to the mid 50s SE.

Canadian high pressure to the NW will push the stalled front
off the coast by Wednesday afternoon and ending the chance for
PoPs across the region. Highs range from the mid 60s N to near
70 S with decreasing clouds. Wednesday night will likely be the
coolest night of the season thus far with cool high pressure
building over the region and a clear sky. Lows will likely drop
into the mid-upper 30s for the Piedmont into portions of the
interior coastal plain and lower 40s elsewhere (away from the
coast). There is a potential for frost Wednesday night,
especially well inland.

Sunny and cool Thursday with high pressure over the region.
Highs are forecast to be in the upper 50s N to low 60s S, with
dewpoints in the 30s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 400 PM Monday...

This period starts off with a 1030+ mb high pressure system
over the area Friday morning. Combo of clr skies along with
nearly calm winds allows for max radiational cooling. MEX
numbers suggest widespread mid-upr 30s for lows except in the
40s along the coast. Thus, the confidence for patchy frost
across the Piedmont is increasing.

The high quickly moves offshore Fri with mid-high level
moisture quickly spreading east from the system to the west. Day
starts off with sun, then increasing clouds. Dry with highs in
the 60s.

Leaned toward the slower ECMWF timing of the moisture fields
rather than the quicker GFS given the strength of the high
moving offshore. The next front progged into the area Fri night
then moves south into the Carolinas Sat. Data suggests southern
stream energy getting tapped and ejecting ne along the front.
Thus, moisture returns with this more of a stratiform rain
rather than showers. Will carry chc pops Fri night. Best
moisture flux / lift Sat morn then gets pushed se Sat aftrn.
High chc to low end likely pops thru 18Z SAt, then start
tapering pops off nw after 18Z but keeping likely pops across
the se. Lows Fri night 50-55. Highs Sat in the 60s.

The front and pcpn push offshore Sat night so will hold onto
chc pops Sat evening then end pops with decreasing clouds after
06Z. Lows in the 40s to low-mid 50s along the se coast.

Another high pressure system builds into the area early next week.
Strong CAA Sun will diminish late. Highs mid 50s nw to mid 60s se.

The high builds over the area by 12Z Mon. Clear skies / diminishing
winds results in another cold night with widespread lows in the mid-
upr 30s except the low-mid 40s along the sern coastal areas. Mstly
sunny and cool Mon. Highs 55-60.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
As of 800 PM EDT Monday...

VFR conditions across area terminals this evening. Surface cold
front currently dropping across the northern Mid-Atlantic will
approach from the NW late this evening and overnight. Mainly
VFR cigs are expected with the frontal passage along with
showers, with the best chc at SBY/ORF/PHF. Cigs potentially drop
to MVFR briefly with frontal passage, with a period of MVFR and
light rain/drizzle then expected Tuesday morning behind the
front, most likely at ORF/ECG. A surge of NNW winds are expected
immediately post frontal with gusts to ~20-25kt along the
coast. Remaining mostly cloudy to overcast Tuesday as the front
stalls over NC and a wave of low pressure approaches from the
SW.

Low cigs along with more showers will bring the potential for
flight restrictions into Tuesday night, mainly across srn/SE VA
and NE NC as low pressure tracks along the stalled front.
Conditions improve Wednesday through Friday as cool dry high
pressure builds into the region.

&&

.MARINE...
As of 545 PM EDT Monday...

Based on some of the latest high res data, a rather decent CAA
surge expected later tonight and Tues morn behind the cold front.
Went ahead and added the lower James River to the SCA and
beefed up some of the gusts in the CWF for now.

PVS DSCN:
Yesterday`s high pressure continues eastward into the Atlantic
as a surface trough and cold front associated with low pressure
across Ontario approaches the area. Southwesterly winds 10-15
with sporadic instances of 15-20 kt across the marine zones this
afternoon. Winds will increase into the evening hours as the
pressure gradient ahead of the approaching trough/front tightens
with winds 15-25 kt developing after 00Z. Winds will veer from
southwesterly to northwesterly after frontal passage tonight.
With cooler air and warm water temps across the marine zones
allowing higher momentum winds aloft to mix down, SCA conditions
are expected tonight and into Tuesday. Currently have the SCA
expiring at 15Z but some of the northern zones may fall below
thresholds a bit earlier.

High pressure builds in for a short while on Tuesday afternoon
into early Wednesday prior to a reinforcing cold frontal passage
across the area Wednesday night and early Thursday. Dry and
cold continental air behind this front will allow northwesterly
winds to reach SCA thresholds and may get close to Gale
territory. Will hold off on hoisting any headlines regarding
this second front as it is still a few periods away and
questions remain regarding timing and magnitude of the winds,
but will continue to closely monitor this period in subsequent
forecasts. Quiet marine conditions are forecast to return for
the second half of Thursday and into Friday as surface high
pressure builds into the area.

&&

.HYDROLOGY...
As of 1000 PM Monday...

Numerous river flood warnings continue on the Nottoway,
Meherrin, Appomattox basins, but levels have dropped below flood
stage on the James so have cancelled headlines there. Also, have
re-issued the areal flood warning for locations along the
Mattaponi River where the level is still steady or slowly rising
at Beulahville and a new warning for Bryants Corner SE of KEMV.
See FLWAKQ/FLSAKQ for site-specific details.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 11 AM EDT Tuesday for ANZ630>632-
     634-638-650-652-654-656.

&&

$$
SYNOPSIS...AJZ
NEAR TERM...AJZ/MAM
SHORT TERM...AJB/AJZ
LONG TERM...MPR
AVIATION...AJZ/MAM
MARINE...MPR/RHR
HYDROLOGY...