Scientific Forecaster Discussion
fxus61 kakq 170140
Area forecast discussion
National Weather Service Wakefield Virginia
940 PM EDT sun Jun 16 2019
high pressure anchored off the southeast coast for most of the
upcoming week. A weak frontal boundary approaches from the
northwest Monday and Tuesday.
Near term /until 6 am Monday morning/...
as of 940 PM EDT Sunday...
Removed all pops from the grids overnite per the latest high res
data showing the convection across the nrn Delmarva stays north
of the area as it moves east while the convection from the
complex to the west weakens as it stays west of the fa overnight.
Fair to pt cldy overnite with lows in the upr 60s-lwr 70s.
Short term /6 am Monday morning through Wednesday night/...
as of 330 PM EDT Sunday...
A weak frontal boundary will sag slowly Monday and Tuesday, with
a gradual increase in shower/storm coverage expected, as a series
of weak perturbations ride quasi-downslope flow aloft along the
approaching frontal boundary. Strong sfc heating and seasonally
robust low-level moisture increasing to +1.5 to 2 S.D. By
Tuesday evening) will lead to the potential for a few strong to
severe storms on Monday, mainly along and north of the I-64
corridor closer to enhanced mid-level westerly winds. Storm Prediction Center has
continued a slight risk over the northern one-third of the local
area...stretching generally from Louisa east-southeast to the Eastern
Shore...where the potential for more organized convection is
greatest. A marginal risk area continues for the rest of the
area for tomorrow. Effective shear is marginal at best, but
given strong heating/lift could yield a few damaging wind gusts
and locally heavy rainfall. Daytime high temperatures will
continue to be quite warm with low 90s expected on Monday.
Overnight low temps will be mild, in upper 60s and low 70s.
Dropped pops a bit Monday night, as meager shear likely portends
to convective activity quickly waning with loss of heating...with
the possible exception of the northern third of the area closer
to the boundary. Otherwise partial clearing overnight and
remaining mild with overnight lows in the mid 60s to low 70s.
Tuesday will be much like Monday with the front inching closer
the area. Slightly increased shower and storms chances are
forecast with the potential for a few strong storms across the
region once again. Highs Tuesday will continue in the upper 80s
and low 90s. Unsettled weather pattern continues for Wednesday
with moist SW flow and strong daytime heating allowing for
additional scattered to numerous showers and storms. Highs in
the upper 80s and low 90s with overnight lows remaining in the
upper 60s and low 70s.
Long term /Thursday through Sunday/...
as of 330 PM EDT Sunday...
A shortwave will be moving off the coast Wednesday night with a
few linger showers. Another trough will be deepening in the
central MS River Valley and expected to move east into our area.
This will bring a decent chance of showers/thunderstorms
(50-60% along a weak cold front) later Thursday afternoon and
into Friday morning as a sfc low tracks over PA and off the New Jersey
coast. A ridge aloft will build over the western Great Lakes as
the trough moves off the mid Atlantic coast, putting the area in
a northwest flow aloft. This will dry US out over the weekend with
slightly drier air at the sfc as well. There may be storms
moving southeast out of the mountains Sunday in the northwest flow, mainly NE
Guidance have been increasing the temperatures for Thursday
ahead of the cold front, highs will be near 90 to the low 90s.
Behind the front, highs will be in the mid to upper 80s Fri-sun.
Beaches will be cooler on Saturday with an onshore flow (highs
ranging from upper 70s to low 80s).
Aviation /02z Monday through Friday/...
as of 700 PM EDT Sunday...
VFR conditions thru the forecast period as the offshore high
dominates. SW winds aob 10 kt. Sct convection psbl across the
north Mon aftrn. Kept pcpn out of fcst but did go with a broken cumulus
deck at both ric/sby after 18z.
Outlook: scattered diurnal convection psbl thru most of the week.
Greatest chcs will be north of a ric-sby line.
as of 330 PM Sunday...
Surface high pressure is anchored off the southeast coast this
afternoon, with low pressure and a frontal boundary over the lower
Great Lakes/northeast. A modest pressure gradient is being created
between these features, which will cause winds to remain elevated on
the ches Bay, lower James River and coastal waters north of
Parramore Island thru early evening before diminishing. For that
reason, scas will remain in effect thru 7 PM for the lower James and
ches Bay for SW winds 15-25 kt. Similar winds for the northern
coastal waters, with seas of 3-5 ft lingering through about 10 PM.
Have extended Small Craft Advisory in time to account for this.
High pressure remains anchored off the southeast coast Monday
through Thursday, as a stationary boundary remains to our N/NW. At
this time, sub-Small Craft Advisory conditions are expected to prevail with a SW wind
averaging 10-15kt, and seas/waves averaging 2-3ft/1-2ft. There is an
increasing chc of aftn/evening showers/tstms Monday through
Thursday, and there is a potential for nocturnal wind shifts to north/northwest
(especially across the nrn portion of the marine area) in the wake
of any organized convective systems.
as of 940 PM EDT Sunday...
The Flood Warning at Sebrell was cancelled this eve.
Marine...Small Craft Advisory until 10 PM EDT this evening for anz650-