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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 181411
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
1011 AM EDT Sun Jun 18 2017

.SYNOPSIS...
High pressure off the southeast coast continues the warm and humid
conditions through Monday. A cold front approaches from the west
late Monday...then stalls over Southeast Virginia and Northeast
North Carolina through the middle of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Another warm/humid day on the way...w/ sfc hi pres still located
in the wrn Atlantic. Deeper layered SSW flo will be lead to a
bit lower PoP the rest of the day as compared to previous two.
Maintaining 15-20% PoP over much of the FA...otherwise
(becoming) partly sunny. Highs in the u80s-l90s...except 80 to
85F at most beaches. Heat indices reaching 95 to 100F (esp
inland).
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
Any lingering convection weakens/disspiates after sunset. Otw, pt
cldy warm and humid with lows in the low-mid 70s.

Things get interesting Monday through Tuesday as ample moisture
combines with a slow moving cold front. At this point, data
suggests most of Monday (through about 21Z) will not be an issue
as only sct pre-frontal convection develops. In fact, enough
heating early in the day allows temps to reach the upr 80s to
near 90. Its after 21Z that a line of convection drops south
into the AKQ fa then slowly drifts SSE across the region Monday
night. This is where SPC has kept us in a DAY 2 slght/marginal
risk for severe storms (enhanced risk just north of the AKQ fa)
with damaging winds being the main threat but can`t rule out
some large hail accompanying the initial storms given the
instability the environment will have to work with. Thus, kept
low chc pops through 18Z then ramped up to likely across the
piedmont after 21Z.

Models show the event turning into a heavy rain producer Monday
night as slow moving (training) storms ever so slowy drift SSE
given the high pw`s as the boundary becomes parallel to the flow.
Best support for heavy rainfall will be across the northern half
of the fa between 00Z-06Z Tue where 1-2+ inches of rain could
easily fall. Thus, kept categorical pops but added R+ to the
grids most areas of VA/MD. May eventually need some sort of a
flood watch as well. The steadiest and heaviest rainfall may not
get to sern VA/NErn NC until after midnight. By then, the intensity
is progged to weaken a bit with high chc to likely pops. Lows in
the upr 60s-mid 70s. Will continue to highlight this event both
in the HWO and social media.

The front sags south and is progged to stall across SERN VA / NErn
NC Tuesday. Thus, pops continue across the southern half of the fa
Tuesday ramping up to likely after 18Z with the potential for heavy
rainfall across those areas. Drying out across the north. Cooler
with highs 80-85.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A frontal boundary lingers in vicinity of the coastal plain of
SE VA and the Carolinas Tuesday night/Wednesday resulting in
some lingering 30-40% PoPs in those areas. Adjusted pops across
the SE Tuesday evening upwards a bit based on the progged frontal
position. The latest data supports relatively dry conditions
Thursday then potential for diurnal convection Friday into next
weekend but uncertainty is high at this time. Highs in the 80s
Wednesday/Thursday, then maybe creeping back into the low 90s
Friday/Saturday. Lows in the 60s and 70s.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
Expect the MVFR ST cloud deck to slowly lift into a VFR SCT-BKN
CU layer later this morning. Kept VCSH next few hours at ECG per
current radar loop of the shwrs moving NNE along the Outer Banks.

Only ISLTD convection expected between 18Z-00Z. Thus, the chc is
still to low to include at any one TAF site attm. Went with a BKN
CU deck instead.

Outlook...A cold front drops into the area Monday night and Tuesday.
Strong to psbl severe storms along with hvy rain with this boundary.
Sct convection expected through mid week as the boundary stalls across
the area.

&&

.MARINE...
The pressure gradient tightens today ahead of a cold front that
will push across the Midwest towards the TN Valley this
afternoon/evening. South winds 5-15kt this morning will increase
to 15-25kt (gusts up to 30kt coastal waters) this afternoon.
Seas 3-4ft this morning will build to 4-6ft north of Cape
Charles Light and 3-5ft south. Waves in Ches Bay will average
2ft this morning and then build to 3ft this afternoon with
pockets of 4ft in the middle of the Bay. SCA flags are in effect
for the nrn coastal waters with the rest going into effect at
100 PM this afternoon. A lull in SCA conditions should be
anticipated for Currituck Sound and Ern VA rivers late tonight
through Monday morning. However, the pressure gradient tightens
up even more by Monday afternoon with the cold front closing in
on the Appalachian mountains. A return to SCA conditions early
Monday afternoon (S-SW winds 15-25kt all waters with gusts up to
30kt coastal waters) has resulted in an extension to SCA flags
through Monday night Bay/Sound/Rivers and through Tuesday morning
for coastal waters. Seas are expected to build to 5-7ft north
of Cape Charles Light during this secondary surge. Waves still
averaging 3ft.

SCA conditions subside by Tuesday morning with SW winds diminishing
below 15kt all waters, however SCA flags for coastal waters will
continue through the morning due to seas being slightly slower to
subside below 5ft. For Tuesday afternoon through the rest of the
week, generally southwest winds at sub-SCA speeds will prevail.
Seas 2-4ft. Waves 1-3ft.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 1 AM EDT Tuesday for ANZ635>638.
     Small Craft Advisory until 6 AM EDT Tuesday for ANZ630>634-658.
     Small Craft Advisory until 10 AM EDT Tuesday for ANZ654-656.
     Small Craft Advisory until 1 PM EDT Tuesday for ANZ650-652.
-- End Changed Discussion --

&&

$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB
SHORT TERM...ALB/MPR
LONG TERM...JDM/MPR
AVIATION...MPR
MARINE...BMD