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fxus61 kakq 280603 
afdakq

Area forecast discussion
National Weather Service Wakefield Virginia
203 am EDT Fri Apr 28 2017

Synopsis...
a cold front approaches the region overnight, stalling over the
area overnight before weakening. Strong high pressure then
prevails just off the southeast coast for the rest of Friday
through the weekend...bringing warmer and more humid conditions
to the area.

&&

Near term /until 6 am this morning/...
latest wx analysis reveals surface low pressure over NE Ohio/northwest
PA. Surface front remains well west of the area, with 01z
mesoanalysis revealing a capped/stable environment over the
local area. Have therefore cut back to slight chc T mention
overnight. Otherwise, held on to high chc to low end likely pop
for scattered showers overnight. However, have slowed timing
slightly per radar/Sat data and cams are in good agreement in
bringing a broken line of showers through the area overnight,
which will diminish in areal coverage as it crosses the ric
Metro from SW to NE after 03z. Far southeast zones stay dry most of the
night, with a second area of showers developing after 08z/4 am
as the front drops across the Piedmont before washing out across
the area early Friday morning. Quantitative precipitation forecast overnight on the order of a
tenth of an inch or less.

Cooled overnight lows by a degree or two given current obs and
expectation of scattered showers through the night. Low to mid 60s
northwest zones...mid to upper 60s southeast coastal sections.

&&

Short term /6 am this morning through Sunday/...
the front washes out along the coastal plain Friday morning
with lingering showers and storms possible across NE NC and
extreme southeast Virginia into late morning. Precip totals for Friday should
be 0.05 inches or less as pwats steadily decrease. Another warm
day on tap with highs reaching the mid 80s inland VA, lower 80s
inland NE NC and Maryland/Virginia Eastern Shore, and mid 70s to lower 80s
beaches.

Weak high pressure builds in behind the front as it washes out
off the Carolina coast. The nrn part of the front gets pushed
north-northeast by Friday aftn as it sticks with parent low in nrn
Ontario/wrn Quebec. Meanwhile, stacked high pressure begins to
dominate off the southeast coast. This will allow a warming
trend to remain steadfast through the weekend. Lows Friday night
in the 60s under mostly clear skies. Breezy southwest winds
expected to develop on Saturday and promote excellent mixing
conditions under mostly sunny skies. Highs Saturday in the
upper 80s to lower 90s inland and in the low-mid 80s beaches.
High cirrus to spread into the area from the northwest as a weak
cold front to the north melds/merges with a warm front lifting
into nrn Virginia from a low in the srn plains. Best dynamics for any
shower/thunderstorm development is mainly north of the area,
however far nrn counties could see better precip chances (up to
30% pop) Saturday aftn/evening... whereas the rest of the area
is anticipated to remain dry within the subsequent warm sector.
The combination of the warm front located north of the area and
southwest winds of 5-10mph Saturday night will result in warm
overnight lows in the upper 60s to low 70s (mid 60s beaches).
Once again, the region remains well within a warm sector on
Sunday with a cold front crossing the mid-Mississippi Valley.
Highs 86-90f inland and 75-84f immediate coast.

&&

Long term /Sunday night through Thursday/...
there will be increasing chcs for showers and tstms FM the west
late Sun night into Mon morning, as a cold front pushes into the
mtns. That cold front will push thru the mts by late Mon, then
cross the area and move off the coast Mon night into Tue
morning. Have maintained high chc to likely pops for showers/tstms
FM Mon aftn into Tue morning. Lows Sun night will range thru the
60s. Highs on Mon in the upper 70s to mid 80s. Lows Mon night
mainly in the upper 50s to mid 60s. Weak high pressure will
provide dry wx for later Tue morning thru Wed, as it slides
from the Gulf Coast states to off the southeast coast. Highs on Tue
and Wed mainly in the mid to upper 70s. Lows Tue night ranging
thru the 50s to near 60. Another low pressure area will lift FM
the lower MS valley twd the Ohio Valley Wed night thru Thu. This
will result in increasing chcs for showers or tstms, esply
during Thu. Lows Wed night in the mid 50s to lower 60s. Highs on
Thu in the upper 60s to mid 70s.

&&

Aviation /06z Friday through Tuesday/...
latest surface analysis depicts the cold front over the central
Appalachians with a weak surface trough over the local area.
Widely scattered showers with embedded thunder (ts indicated at
kric) have lifted into central Virginia early this morning,
with another area of showers developing over eastern North
Carolina. Main threat from thunderstorms will be locally heavy
rain. Widespread VFR conditions observed with southerly winds
generally at or below 10 knots. Scattered showers with embedded
thunder lift across the eastern local area between 08-12z this
morning as a weakening cold front drops over the Piedmont.
Increasing low level moisture will drop ceilings to MVFR for a
period between 11-17z this morning across the southeast. NAM/met
guidance remain pessimistic with IFR conditions, but believe
moisture is being overdone in the low levels so have kept
conditions MVFR. Thereafter, showers push offshore with another
chance of afternoon showers/thunderstorms across southeast
Virginia and northeast North Carolina. Winds become southwest
then south at or below 10 knots.

Outlook...mainly dry weather expected over the weekend. Next
frontal boundary expected late Monday into Tuesday with
possibility of shwrs and tstms.

&&

Marine...
late this aftn, a weak cold front was pushing into the mtns.
Winds were mainly south-southwest 10 to 15 kt over the waters. That weak
front will approach FM the west tonight, then dissipates as it
slides into the nrn waters Fri morning. South winds will
increase a bit tonight, helping to maintain or build seas to 4
to 6 ft over the nrn three coastal zns. So, have maintained Small Craft Advisory
for these zns into Fri morning. Otherwise, expect south-southwest winds to
remain below Small Craft Advisory criteria.

A disorganized pressure pattern will produce south-southeast winds arnd 10
kt or less over the waters during Fri. Generally south-southwest winds 15 kt
or less will prevail over the wates Fri night thru sun, as sfc
high pressure sets up off the mid Atlc/southeast coast. Waves 1 to 2 ft
and seas 2 to 4 ft.

Another deep low pressure system will move thru the upper Midwest
early next week. This along with an approaching cold front will
increase the pressure gradient locally, with sca's likely Mon
and Mon night.

&&

Climate...
it appears likely that Richmond and Norfolk will end the month
with the warmest April on record. Warm temperatures during most
of the month combined with an unseasonably warm period to end
April are expected to push the average temperature above that
which occurred in 1994. At Richmond, the previous record was
63.2 and at Norfolk it was 64.7. Both were set in 1994. This
month's temperatures could be around a degree above those
values.

&&

Akq watches/warnings/advisories...
Maryland...none.
NC...none.
Virginia...none.
Marine...Small Craft Advisory until 1 PM EDT this afternoon for anz650-
652-654.

&&

$$
Synopsis...mam
near term...bmd/mam
short term...bmd
long term...tmg

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