Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KAKQ 201424
Area Forecast Discussion
National Weather Service Wakefield VA
1024 AM EDT TUE SEP 20 2016
-- Changed Discussion --A frontal boundary remains stalled near the coast through
Wednesday. Meanwhile, low pressure will linger over the outer
banks of North Carolina into tonight, then drifts southwest to
along the southeast coast during Wednesday. High pressure slowly
builds into the region late in the week.
-- End Changed Discussion --
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --Late this morning, a frontal boundary remains stalled near the
coast...while remnant lo pres was spinning over the outer banks of
NC. Deep layered tropical moisture feed will continue along the
coast and affect ern and srn portions of the cwa this aftn into
this evening. Widespread shras and isolated tstms are expected
fm the VA Ern Shore SSW acrs the area. While, the cntrl VA
piedmont N of RIC WSW to FVX area will have just isolated or sctd
showers. Rainfall amounts of 1-4 inches are expected near the
coast, esply in S Hampton Roads to coastal NE NC ,up to 1 inch
possible to about the I 95 corridor in cntrl/s cntrl VA. Thus,
a Flash Flood Watch will remain in effect for far SE VA and
coastal NE NC (through this evening). Though there is some
concern farther N along portions of the ern shore (where the last
few runs of RAP13 guidance suggest enhanced rain potential-and
some of that area received excessive rain on Mon). Otherwise,
mostly cloudy to cloudy over the local area this aftn...highest
PoPs (to 100%) in SE VA-NE NC...tapering to 15-30% well to the WNW
away fm the coast. Highs will range fm the mid 70s to near 80.
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.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
Frontal boundary and lo pres sfc-aloft will remain along the coast
from VA to the Carolinas through Wed...before breaking down slowly
during the end of the week. A continuation of hi pcpn chances
tonight-Wed...mainly over SE VA and NE NC...before slowly lowering
heading into Thu. Additional moderate-heavy rainfall possible and
later shifts may need to consider extending Flash Flood Watch if
necessary. Continuing to remain mostly cloudy across all but far N
and W areas in FA into Thu.
Lows tonight/Wed night from the m60s NW to the l70s SE. Highs
Wed/Thu in the u70s SE to the l80s NNW.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
The mid-level circulation dampens and begins to retreat
Thursday night into Friday as an upper ridge builds across the Ohio
Valley and a trough digs over se Canada. This should result in
gradually improving conditions. Sky cover should trend from mostly
cloudy to partly cloudy, with 20-30% PoPs Thursday night trending to
~20% Friday. Lows Thursday night range from the upper 60s to around
70, with highs Friday in the low/mid 80s. The trough digs over the
Northeast US Saturday into Sunday, which pushes a cold front swd
through the Mid-Atlantic Saturday night into Sunday. Partly sunny
and warm Saturday ahead of the front with highs in the low/mid 80s.
12z/19 data suggests temperatures will actually trend toward
seasonal averages Sunday into Monday, which is highs in the
mid/upper 70s and lows in the mid/upper 50s. There is only a slight
chc PoP associated with the frontal passage as moisture is limited.
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
Stalled frontal boundary near the coast and a tropical moisture
feed nwd will continue to produce widespread shras (isolated
tstms and moderate/heavy ra) and periods of IFR/MVFR conditions
through the day (highest prob at PHF/ORF/ECG). Otherwise...IFR-
MVFR conditions will persist elsewhere...though shras will likely
be more SCT.
Forecast for the next several days has low level of confidence as
upper level low and associated weak surface low remains stalled
invof coastal NC/SE VA. Periods of showers and a few thunderstorms
will be possible at least through Thursday with some IFR possible.
High pressure is slow to build into the region from the N by later
Update as of 7 AM...latest obs continue to show ENE winds 15-20kt
with gusts to 25 kt across the lower Ches Bay and southern coastal
waters with a slight uptick in seas as well (up to 4 ft now).
With the hi-res guidance now showing little if any lull in the
winds through the day have decided to go ahead and begin the SCA
for the aforementioned areas.
Previous discussion...The low associated with the remnants of
Julia will linger in the vicinity of the NC coast through
Wednesday morning and then gradually push farther inland by late
Wednesday into Thursday. Winds thru much of today will generally
remain ENE 10-15 kt but there may be periods of brief elevated
winds to 20-25 kt in heavier showers. Due to the influence of
Julia, the gradient then tightens late this afternoon and
especially tonight/Wednesday with an E wind increasing to 15-20kt
across the ocean/lower Bay/lower James. Seas build to 4-6 ft as
early as this evening across the southern ocean waters and by Wed
morning as far north as Chincoteague. Waves will reach 3-4ft in
the lower Bay and up to 5 ft at the mouth. Have issued SCAs for
these areas beginning late this afternoon into Wed. The gradient
begins to weaken Wednesday night into Thursday, with the wind
diminishing and seas gradually subsiding. The low finally
dissipates by Friday, with a cold front approaching from the north
Increasing onshore flow tonight into Wednesday has the potential to
push tidal anomalies to around 1.0-1.5ft above normal across the
lower Bay and lower James. This could push some locations near minor
flooding thresholds during high tide Wednesday afternoon. Elsewhere,
expect tidal departures to average 0.5-1.0ft above normal.
A beach hazard statement will be in place today due to a high threat
of rip currents across the southern beaches.
NC...Flash Flood Watch through this evening for NCZ015>017-031-032-
VA...Flash Flood Watch through this evening for VAZ095-097-098.
MARINE...Small Craft Advisory until 6 PM EDT Wednesday for ANZ632-634-
Small Craft Advisory from 6 AM to 6 PM EDT Wednesday for
Small Craft Advisory from 10 PM this evening to 6 PM EDT
Wednesday for ANZ652-654.