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-- Discussion containing changed information from previous version are highlighted. --
313
FXUS61 KAKQ 271942
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
342 PM EDT Sat May 27 2017

.SYNOPSIS...
-- Changed Discussion --
A weak cold front will sink south through the region this
evening and overnight. The front will drop into the Carolinas
Sunday, and then return north as a warm front Sunday night.
Another cold front approaches from the northwest on Memorial
Day.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
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Storm complex was ongoing this afternoon across east-central KY
pushing east with the upper wave. Showers and a few storms were
also oriented E-W along the cold front across MD and WV. Dry air
in the mid levels has kept convection at bay thus far evident in
the CU field as clouds develop, but then entrain dry air.

Though convection is being delayed, there is till concern over
the development of showers and storms in the NW flow as the
front drops south and upper wave approaches from the west.
Instability is still lacking this afternoon, but there may still
be a window this evening where things come together mainly along
and south of I-64. Given the thermal profiles if we do see
severe storms the primary threat will be hail and damaging
winds. 0-1km MLCAPE values are still progged to reach 1000-1500
J/kg wither side of the NC/VA border, with a decent mid/upper
level speed max resulting in 0-6km bulk shear of 40-50kt.
Downdraft potential remains rather high if storms can develop
given thermal profiles.

Any showers or storms which develop should push quickly east
and southeast with little to no precip possible in the southeast
after midnight. The chc for showers/tstms diminishes NW- SE
tonight with lows generally in the 60s.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
-- Changed Discussion --
The initial shortwave trough pushes offshore Sunday morning,
with shortwave ridging building over the Mid-Atlantic. The
surface cold front drops into the Carolinas Sunday with N/NE
flow developing across the region in the wake of the mid-level
trough and surface cold front. Variably cloudy with some patchy
morning stratus or fog possible. Cooler over the Ern Shore with
highs in the low/mid 70s. Highs generally in the low/mid 80s
for central/srn VA and interior NE NC.

The surface boundary returns newd into the region late Sunday
aftn into the evening and early overnight hours. This will
combine with another shortwave trough resulting in an increasing
possibility of showers/tstms approaching from the west during
the evening and overnight hours. 0-6km bulk shear rapidly
increases to 35-45kt after 00z resulting in a chc of a few
strong to marginally severe tstms mainly during the evening.
Mostly cloudy with lows in the 60s.

A cold front will be crossing the mountains Monday morning, and
then continue ewd Monday aftn. Additional showers/tstms are
expected Memorial Day aftn/evening. There is some model
disagreement with respect to coverage, so PoPs will remain
30-50%. Increasing WSW flow aloft ahead of a trough digging
across the Great Lakes will yield 0- 6km bulk shear values of
40-50kt. This will combine with 1000-2000 J/kg of 0-1km MLCAPE
resulting in the potential for severe thunderstorms. Partly
sunny then mostly cloudy on Memorial Day with highs ranging
through the 80s, with the potential for near 90 SE, and 70s
along the Atlantic coast of the Ern Shore.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The long term period beginning Tuesday night features near normal
temperatures and generally low chances for precipitation. Weak and
poorly defined frontal boundaries affect the area and confidence in
the details of the precipitation forecast are rather low.
Thunderstorm chances Wednesday were kept relatively low as weak high
pressure builds in. A frontal boundary moves in for Thursday and
settles just off the coast Friday and Saturday. Highest POPs (30 to
40 percent) are currently set for southern portions on Friday
afternoon and evening.

High temperatures are forecast to range from 80 to 85 Wednesday and
Thursday and the upper 70s to around 80 Friday and Saturday.
Readings will be a bit lower near the coast. Lows are expected to
range from 60 to 65.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
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As of 17z...conditions were fairly quiet across the area with solid
VFR conditions. River breezes were apparent on the NEXRAD
reflectivity and winds at ORF were out of the northeast off the Bay.
Still expect convection to develop late in the afternoon and have
TEMPO groups for thunderstorms at RIC from 22 to 00Z and at the three
southeast sites from 00 to 02z. These will be updated as needed.
Strong to possibly severe winds gusts (50kt or higher) will be
possible with the thunderstorms.

Model consensus suggest widespread stratus for Sunday morning which
would be reasonable given wet ground conditions from precipitation
     limited low level mixing and developing onshore flow. Included
low ceilings at RIC with a broken to overcast sky across the
area through.

OUTLOOK...The chance for showers/tstms returns Sunday evening/night
and again Monday aftn/evening. Minimal chances for aftn/evening
showers/tstms persist into Tuesday through Thursday. Stratus
and patchy fog will be possible each morning.
-- End Changed Discussion --

&&

.MARINE...
Latest surface analysis places a weak ridge of high pressure over
the water with an area of low pressure over the Ohio Valley. Winds
are generally light and variable, with speeds at or below 10 knots.
Waves ~1 foot and seas 1-2 feet. The ridge axis slides offshore this
morning as low pressure approaches from the northwest. An associated
cold front reaches the waters this afternoon. Flow becomes south to
southeast around 10 knots. Seas 2-3 feet. Low pressure pushes across
the waters tonight as the front drops over North Carolina. Flow
becomes northerly at 10-15 knots. Low pressure stalls offshore
Sunday as high pressure nudges in from the northeast. Flow becomes
onshore through Sunday evening at 10-15 knots. The next area of low
pressure lifts over the eastern Great Lakes region Sunday night and
into eastern Canada on Memorial Day. A trailing cold front reaches
the waters late Monday into Monday night, stalling along the coast.
The front washes out as high pressure slowly builds in from the west
through Wednesday. Winds generally at or below 15 knots. High
pressure prevails through the end of the work week.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.

&&

$$
SYNOPSIS...AJZ/JAO
NEAR TERM...AJZ/JAO
SHORT TERM...AJZ/JAO
LONG TERM...LSA
AVIATION...AJZ/LSA
MARINE...SAM