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000
FXUS61 KAKQ 040839
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
439 AM EDT Sat Apr 4 2020

.SYNOPSIS...
Strong low pressure well offshore of the local area continues to
move away from the coast today as high pressure builds over the
area. High pressure moves offshore on Sunday. A weak cold front
approaches the area late Sunday before crossing part of the area
on Monday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 345 AM EDT Saturday...

Low pressure well offshore of the VA/NC coast continues to track SE
and away from the area early this morning. However, there is one
last shortwave near the MD/PA border that is moving south toward the
area. N-NNE winds have diminished and are light/calm well inland,
but are still gusting to ~15 mph near the coast. Skies are
mainly clear over most of the area, with mostly cloudy-overcast
skies over the Lower Ern Shore. Temperatures have fallen into
the 40s-low 50s in most areas, with a few upper 30s across
interior srn/SE VA. Expect temperatures to fall no lower than
40F across most of the area by sunrise, with mid-upper 30s over
portions of interior S/SE VA. The weak shortwave in northerly
flow aloft will drop southward toward the area today. Not
expecting any pcpn from this feature (outside of perhaps a few
sprinkles over the Ern Shore) but clouds will be on the increase
across most of the region today. Expect skies to become mostly
cloudy over much of the area by aftn. There will be a bit more
sunshine across the Piedmont and very little (if any) sun over
the Lower MD Ern Shore. As such, temperatures will be warmest
across the VA Piedmont where mid to upper 60s are forecast.
Expect low to mid 60s for the I-95 corridor with mid 50s-low 60s
for coastal zones. Weak high pressure currently centered over
the Great Lakes/OH Valley builds overhead tonight. Lows range
from around 40F E/SE (closest to the center of the high) to the
low 40s W. Some of the CAMs are hinting at the possibility of
patchy fog across the Lower Ern Shore as well as portions of SE
VA/NE NC. Will leave this out of the grids for now, but will
re-assess later this morning.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 345 AM EDT Saturday...

Weak return southerly flow commences on Sunday as high pressure
moves offshore. Continued dry with highs in the low 70s inland,
with mainly mid-upper 60s near the bay/coastal SE zones, and
low-mid 60s over the Lower Ern Shore. Shortwave energy in WNW
flow aloft will approach the area late Sunday-Sunday night. At
the same time, a weak cold front slowly moves south toward the
area (but remains to our NW through Sun night). A few showers
will likely develop to our W late Sun before potentially moving
across the area Sun night. Will keep it dry through 21z Sun.
Will have PoPs of 15-30% over the area Sun night to account for
isolated to perhaps scattered showers. Lows Sun night will be in
the upper 40s and low 50s. A 15-30% chc (highest SE) for a few
showers will continue Mon AM as the aforementioned front crosses
the region from N to S. Some re-development of showers is
expected along/ahead of the front Mon aftn (mainly over far srn
VA/NE NC) as temperatures warm into the low-mid 70s and dew
points rise into the mid 50s. Forecast soundings do show some
weak instability across NE NC Mon aftn, so cannot rule out a
rumble of thunder or two (although upper forcing will be meager
at best). Elsewhere (on the north side of the front), pcpn
chances end by mid-late aftn. Warmer on Monday with highs
ranging from the upper 60s near the coast to the low-mid 70s
elsewhere. The weak boundary moves back N as a warm front Mon
night as low pressure tracks ewd across the nrn Plains. Will
keep slight chc PoPs across NE NC through 06z Tue, with a slight
chc of a shower late over the Lower MD Ern Shore.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 400 PM EDT Friday...

A series of weak, low amplitude waves will move through the region
early next week, providing slight chances of showers Monday night
through Wednesday. A weak warm front lifts N Monday night into
Tuesday before stalling to the N and lingering through Wednesday. A
backdoor cold front moves through the region Wednesday
night/Thursday but should be mostly dry. A cold front moves through
Thursday night/Friday morning from the W and provides another
isolated chance of showers. Greatest PoPs will be Tuesday morning
(30-45% chance)and Wednesday morning (25-40% chance).

Highs are expected to be in the mid-70s on Mon and Thurs, upper 70s
to near 80F on Tues and Wed, and low-mid 60s on Fri. Lows expected
to range from the low 50s N to the upper 50s S on Mon, Tues, and Wed
nights. Lows are expected to then cool to the low 40s N to the upper
40s S Thurs and Fri nights behind the stronger cold front.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
As of 135 AM EDT Saturday...

Skies are mainly clear across VA/NC early this morning, with BKN
CIGs around 5000 ft at SBY as strong low pressure well off the
VA/NC coast continues to drift SE away from the area. Skies
become BKN inland/BKN-OVC near the coast today as a secondary
upper shortwave drops toward the area from the N. However, CIGs
at RIC are likely to remain VFR (4000-5000 ft). CIGS will likely
drop to MVFR at the other terminals by late morning-midday.
There is still a very slight (10-15%) chance of a light rain
shower at SBY through this morning, but any light pcpn that does
fall will not have any operational impact. CIGS scatter out
from this evening through the first part of tonight as high
pressure settles into the area. There is a slight chc of patchy
fog at the coastal terminals after 06z Sun, but confidence in
this is low attm. N-NE winds will average 8-12 kt through the
TAF period, with a few gusts to 20 kt likely at ORF/ECG.

Outlook...VFR conditions are expected for much of Sunday
although a weak front will approach from the west late in the
day. Unsettled weather sets up for early next week with chances
of rain Monday through Wednesday, with occasional degraded
flight conditions possible.

&&

.MARINE...
As of 400 AM EDT Saturday...

Sfc low pressure now located well off the VA coast, with winds
now slowly diminishing across the region. Allowed SCAs to expire
for all rivers except the lower James. SCAs remain in effect
through 7 or 10am for the lower James, most of the Bay, and
Currituck Sound but will stay in effect much longer/into Sun
for the mouth of the Bay for swell that will bring waves of 4
ft+ despite the diminishing wind. For the coastal waters, SCAs
remain in effect through Sun night, initially today we will
continue with gusts to 25kt, but the main hazard will be from
seas that will increase to 7-9 ft later today/tonight before
gradually subsiding to 5-6 ft Sun aftn/Sun night. This will be
from 12-13 sec long period swell from the low pressure well
offshore.

High pressure will settle across the local area Sun, before
drifting SE to the NC coast Sun night. Winds will be light and
mainly onshore Sunday, then become SE ~10 kt Sunday night. Seas
may stay above SCA criteria (5 ft) into Monday though current
forecast has them subsiding to ~4ft by then. A weak cold front
is expected to shift the winds to the N on Mon for much of the
marine area but there is no real cold air surge and the front
is expected to wash out or lift back N Mon night.

&&

.TIDES/COASTAL FLOODING...
As of 400 AM EDT Saturday...

N to NE winds 15-20 kt this morning will gradually diminish and
the main concern for tidal/coastal flooding will be a result of
long period (12-13 sec) swell from strong low pressure well off
the mid-Atlantic coast. Seas have been underperforming thus far
but are now building to 6-7 ft across the northern coastal
waters and to 4-6 ft over the S. Have scaled back by about a
foot for the maximum seas that are expected later today into
tonight (building to 8-9 ft offshore and 7-8 ft nearshore). Have
held off on a High Surf Advisory as the chance for nearshore
waves to 8 ft looks less likely now (though will continue to
monitor this closely).

However, the currents data at the mouth of the Chesapeake Bay is
showing that the last tide did not ebb (at all) with another
flood tide increasing as of this writing. Seeing the response
into the lower and middle Bay now so have extended the Coastal
flood Advisories to cover both the upcoming high tide later
this morning as well as the following high tide this evening.
Also did this for the advisories along the Atlantic coast. Some
locations may struggle to hit minor flood thresholds with the
high tide this morning (but all will be at least within a few
tenths). With the increasing swell coupled w/ winds slowly
diminishing and shifting more to the NE, expect to see the
increasing anomalies translate northward and bring the potential
for moderate flooding into the mid/upper Bay by this evening
and into Sunday. Thus have raised a Coastal Flood Watch from
portions of the northern Neck and over the bayside of the MD
eastern shore for Somerset, Wicomico, and Dorchester. As we see
how the water levels respond later today, the Watch can be
converted either to an Advisory or a Warning as appropriate.



&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...Coastal Flood Advisory until 9 PM EDT this evening for MDZ024-
     025.
     Coastal Flood Watch from this evening through Sunday afternoon
     for MDZ021>023.
NC...Coastal Flood Advisory until 9 PM EDT this evening for NCZ102.
VA...Coastal Flood Advisory until midnight EDT tonight for VAZ078-
     084>086-089-090-093-095>097-523>525.
     Coastal Flood Advisory until 9 PM EDT this evening for
     VAZ098>100.
     Coastal Flood Watch from this evening through Sunday afternoon
     for VAZ075-077.
MARINE...Small Craft Advisory until 6 AM EDT Monday for ANZ650-652-654-
     656-658.
     Small Craft Advisory until 7 AM EDT this morning for ANZ630-
     631-638.
     Small Craft Advisory until 6 PM EDT Sunday for ANZ634.
     Small Craft Advisory until 10 AM EDT this morning for ANZ632-
     633.

&&

$$
SYNOPSIS...ERI
NEAR TERM...ERI
SHORT TERM...ERI/RHR
LONG TERM...RMM
AVIATION...ERI
MARINE...CP/LKB
TIDES/COASTAL FLOODING...