Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
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FXUS61 KAKQ 211850
Area Forecast Discussion
National Weather Service Wakefield VA
250 PM EDT SUN AUG 21 2016
A cold front will cross the Mid Atlantic region through tonight.
High pressure builds in from the northwest Monday and remains over
the area for much of the upcoming week.
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
-- Changed Discussion --Warm/humid afternoon across the FA w/ vrb clouds and SSW wnds
averaging 10-20 mph. Temps from the u80s-l90s...w/ heat indices
Isolated-SCT shras/tstms continuing to pop...mainly interior
eastern VA so far this afternoon. A little more organized area of
shras/tstms exiting the higher terrain and approaching far WNW
counties. Parameters for strong/severe tstms not that impressive
(thus far). Highest effective shear N of the FA...dCAPE low
(limiting potential for downdrafts)...winds aloft relatively weak.
Overall CU field having difficulty attaining signficant vertical
extent. Models remain weak w/ convective parameters through this
evening as cold front from the W arrives. A bit better SRH
possible for areas NNE of RIC (to the Lower MD Eastern Shore)
where convection may attempt to consolidate this evening (before
Shras/possible tstms shift to the coast after midnight...then end
late. Partial clearing expected wrn portions as winds shift to NW
(post cold front) and drier air begins to arrive. Lows in the
l-m60s NW to l70s SE. NNW winds to become gusty by late tonight
(highest ern portion/along the coast).
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.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
Cold front pushes well S and E of the FA on Mon...to be followed
by sfc hi pres building into the region from the NW. Much
drier/more comfortable air will be overspreading the FA during the
day. N winds will be a bit gusty (highest E portion/at the coast)
in the morning before waning. FEW/SCT CU...otherwise mostly sunny
w/ highs in the m80s.
Sfc hi pres settles over the area Mon night through Tue before
drifting slowly off the coast into Wed. Expecting continued dry
and pleasant through the period. The wind (averaging aob 10 mph)
will become NE Tue...then continue into Wed. Highs Tue-Wed
ranging from the u70s/l80s at the coast...to the l-m80s inland.
Morning lows in the u50s-l60s inland...to the m60s for SE coastal
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Surface ridge axis locates along the coast Thursday as surface
winds become south to southeast. Further modification of dewpoints
and temperatures expected, but dry conditions prevail. Daytime
temps warm into the upper 80`s across the area (cooler again
nearest the coast). Medium range guidance is less amplified than
24 hours ago with a northern stream trough digging into the upper
Midwest and Great Lakes region. The result is a slower and weaker
cold front for late in the week. Have silent POPs for Friday now
with the slower frontal timing, with highs warming into the upper
80`s to low 90`s thanks to southerly winds. The front progged to
now drop into the area Friday night, but with upper level high
pressure over the Southeast states, it will be difficult for the
front to push through the area. Guidance also indicates limited
moisture along the front, so will keep POPs silent Friday night
and Saturday as well. Warm again Saturday with highs in the upper
80`s to low 90`s.
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
A cold front approaching from the nw will move across the region
through 04Z, bringing an increasing chc of showers/tstms this
afternoon and early evening. A few showers/tstms are developing
as of 1730Z, but expect the greatest coverage to be between 20Z
and 00Z. A much drier airmass arriving behind the cold front late
tonight and Monday, persists through Thursday as high pressure
builds over the region. A 4 to 6 hour period of gusty NW winds
expected in the 11Z to 17Z time frame Monday at KSBY/KORF/KPHF,
during period of strongest cold advection behind the front.
Otherwise, after this evening, VFR and light winds will prevail
Weak frontal boundary remains over the region early this morning.
Winds are generally south to southeast at or below 10 knots. Waves 1-
2 feet and seas 2 feet. A cold front currently over the Ohio Valley
drops into the area this afternoon, and crosses the waters this
evening. Southerly winds increase to 10-15 knots ahead of the front
this afternoon, with seas increasing to 2-3 feet. A northwest surge
is expected over the waters tonight as low level cold air advection
combines with low level winds of 25 to 30 knots and warm waters.
Speeds increase to 15 to 25 knots, with several hours late tonight
of solid 20 knots winds over the Bay. Waves build to 3-4 feet late
tonight along with seas of 3-5 feet, highest 20 nautical miles out.
SCA headlines were raise late last night for all waters, including
several hours of SCA conditions in the eastern Virginia rivers. High
pressure nudges in from the west Monday morning as cold air
advection wanes and gradient winds relax. Expect SCA conditions to
subside by late Monday morning or early Monday afternoon with
northernly winds subsiding to 10-15 knots. The surface high builds
north of the waters Monday night and Tuesday, as flow becomes
northeast at 10-15 knots. Onshore, sub-SCA flow persists through
Thursday as high pressure slides off the Northeast coast. The next
front approaches the region Friday, but stalls over or north of the
waters early next weekend.
Due to an azimuth motor failure, the KAKQ 88D will be out of
service until sometime on Monday.
MARINE...Small Craft Advisory from 6 PM this evening to noon EDT Monday
Small Craft Advisory from 10 PM this evening to 10 AM EDT
Monday for ANZ633.
Small Craft Advisory from 4 AM to noon EDT Monday for ANZ650-