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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 290724
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
324 AM EDT Thu Jun 29 2017

.SYNOPSIS...
High pressure will reside off the Mid Atlantic Coast through
Friday. A trough of low pressure will set up over the area for
late Friday night through Saturday.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
1023mb high pressure is centered just off the coast this
morning. Other than some high clouds filtering across the
region, we have quiet conditions with comfortable temperatures
in the 50s and 60s. The high will push further offshore through
tonight with dry wx prevailing. SSW flow will start to increase
today resulting in a warmer afternoon and a slight increase in
humidity. Mostly sunny with highs in the mid to upper 80s.
Mostly clear tonight with lows in the mid to upper 60s.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure remains centered offshore Friday and Saturday,
resulting in warm afternoons with increased humidity levels.
Dry wx will prevail thru at least the first part of Friday for
the entire region. An isolated shower or tstm could affect the
far southern tier of the area Fri aftn/eve. Then, isolated to
sctd showers or tstms will be possible Sat aftn into Sat
evening, as a trough of low pressure sets up over the region.
Highs on Fri will range from the mid 80s to lower 90s. Lows Fri
night mainly in the lower 70s. Highs on Sat in the upper 80s to
lower 90s.
-- End Changed Discussion --

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Long term period will feature a fairly typical summertime pattern
with a cold front weakening near or just N of the area Sat night/Sun
morning. Still capping PoPs at 20-40% Sat night (highest N) as
more significant forcing stays NW closer to the decaying front.
Sunday will see the front wash out across the local area, will
maintain 20% PoPs N/NW and 30% PoPs most other areas (up to 40%
over northeast NC). Highs in the upper 80s to lower 90s. Mon/Tue
will see the local area generally in light flow and minimal
forcing. It will be very warm and humid with enough aftn/early
evening instability for ~20% PoPs most areas (and with a little
more instability will keep PoPs to near 30% for interior NE NC)
Highs 90-95 F inland and mid- upper 80s/lower 90s near the
coast. Lows generally 70-75 F. GFS/ECMWF diverge with respect to
details late Tue/Wed, the ECMWF suggesting building heat and
lower PoPs while the GFS supports slightly cooler wx and a higher
chance for daily tstms. Have genly split the difference and
just carried 20 to 30% PoPs during climo favored timeframe (late
aftn and evening). Highs continue to be 90-95 F inland and
upper 80s/around 90 F along the coast.

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
High pressure moves off the coast today allowing for more of a
southerly flow. A cold front over the Midwest will approach
this weekend and then stall to the north of the area.

High confidence that VFR conditions will continue through the 06Z
TAF period. Mainly clear skies and variable to light S winds
are anticipated overnight. Scattered cumulus, around 6000 feet,
develops mainly after 16Z. Winds increase a bit out of the
south by this afternoon, occasionally gusting to 15-20 knots.

Outlook: Afternoon/evening showers and thunderstorms will be
possible Saturday through Monday.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
Latest weather analysis features Sfc high pressure now centered
along and just offshore the SE VA coast. Low-Level SSE flow
continues this morning ~10-15 kt. A weak surge has allowed winds
to increase over the past few hours, but are still predominately
sub-SCA.

After a brief lull this morning through early afternoon, expect
a slightly stronger surge as pressure gradient tightens between
high pressure offshore and low pressure crossing the upper Great
Lakes/Southern Ontario. SCA headlines for S surge (wind gusts to
20 to 25 kt) now in place for all of the
Ches Bay from this afternoon through late this evening, and through
early Friday morning for Bay zones N of New Pt Comfort. Timing of
strongest winds appears slightly earlier per both hi-res CAMs and
synoptic models coming with the initial surge from mid to late afternoon
through midnight tonight.

Farther south in the Bay and across the rivers, the gradient
slackens a bit faster and therefore expect SCA winds to end a bit
sooner, thus the midnight end time. Farther north, NWPS and Wavewatch
indicate seas increasing to near SCA threshold this evening, mainly
north of Parramore Island. Wavewatch/NWPS blend suggests mainly 4 ft
seas in these areas with the potential for seas approaching 5 ft
out 20 NM offshore. Given that timing is into the second period, and
any SCA over the northern coastal zones would be short-lived and
marginal, will hold off on SCA headline over the coastal waters for
now. Farther south should stay at or below 3-4 ft through the
period. Similar conditions Fri aftn/evening, with another surge
expected Friday afternoon and evening. However, guidance still
maintains that this surge will be slightly slightly weaker compared
to Thu night. A slow moving cold front approaches from the NW Sat
but weakens by the time it reaches the local area on Sunday. Outside
of any tstms, good boating conditions expected over the
upcoming holiday weekend, with sub-SCA conditions expected with
winds 10-15 kt or less and seas mainly 2-3 ft and waves 1-2 ft.
-- End Changed Discussion --

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory from 1 PM this afternoon to midnight EDT
     tonight for ANZ632-634.
     Small Craft Advisory from 1 PM this afternoon to 4 AM EDT
     Friday for ANZ630-631.
-- End Changed Discussion --

&&

$$
SYNOPSIS...JDM
NEAR TERM...JDM
SHORT TERM...JDM
LONG TERM...LKB
AVIATION...AJB/JDM
MARINE...MAM