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000
FXUS61 KAKQ 191946
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
346 PM EDT Mon Aug 19 2019

.SYNOPSIS...
Isolated to widely scattered afternoon and evening showers and
thunderstorms will continue through Wednesday as a weak trough
of low pressure will persist across the region. A stronger cold
front moves though the area late Thursday into Thursday night.
High pressure then builds into the area for the weekend.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 305 PM EDT Monday...

Scattered thunderstorms have developed over the Piedmont through
the Delmarva along the weak lee trough. Some of the storms are a
little stronger across the far north due to the proximity of the
weak upper disturbance noted on Water Vapor. Could not rule out
a severe storm or two late this afternoon into this evening due
to the strong DCAPE in excess of 1000 J/KG and fairly steep low
level lapse rates. Expect these storms to continue through
early this evening then dissipate soon after sunset due to loss
of daytime heating. Otherwise, tonight will be mild but
generally clear with lows only in the low to mid 70s.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
As of 305 PM EDT Monday...

Much of the same for the next few days. May see better activity
east of I-95 tomorrow as the models suggest a weak trough
extending SE across the area. This will serve as a focus for
shower/storm development during the afternoon, with locally
heavy rainfall not out of the question due to the slow movement
of any thunderstorm activity and precipitable water values
around 2 inches. Shower/storm activity will diminish Tue evening
then develop again mainly across the Piedmont Wed aftn along the
lee trough. A stronger frontal boundary moves toward the area
Thursday which will serve as the focus for thunderstorms Thu
aftn/evening. Will go with 40/50 PoPs across the entire area
Thu. Highs Tuesday will once again be in the low/mid 90s, while
Wednesday/Thu may be just a tad cooler due to a little more in
the way of cloud cover. However temps will still be in the lower
90s. Heat index values will once again top out in the 100-104
range on Tuesday.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 305 PM Sunday...

A potent area of low pressure (sfc-aloft) continues to slowly track
tracks across Quebec Thu night-Fri while the trailing cold front
approaches the region from the NW. Convection will likely be ongoing
through a good portion of Thu night as the front (slowly) crosses
the area. Model consensus has the front stalling across srn VA by
12z Fri, while the 12z/19 GFS continues to forecast the front to
clear the area by late Fri AM. On the other hand, the latest
ECMWF/GEM both have the front moving very slowly southward across
the area on Fri before clearing the area sometime this weekend. The
cold front potentially stalls (or very slowly moves southward) from
Fri-next weekend. If the ECMWF/GEM solution verifies and the front
slowly moves across srn portions of the CWA from Fri through the
weekend, this would lead to continued chances of scattered aftn-
evening convection across srn VA/NE NC. Far northern portions of the
CWA likely remain dry next weekend (or see only isolated, diurnally-
driven showers/tstms) as sfc high pressure over the Great
Lakes/Northeast tries to build toward the region. For now, went with
a model blend and have 20-50% PoPs on Fri/Sat (highest S/lowest N).
Dry/comfortable wx prevails late Sun-early next week as sfc ridging
continues to build over the area.

Highs mainly in the low-mid 80s through the extended period with
lows in the 60s (except around 70F in coastal SE VA/NE NC).

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
As of 300 AM EDT Monday...

Expect mostly VFR though the forecast period. Isolated
showers/storms could impact SBY and RIC this aftn into this
evening which may cause brief flight restrictions but the
chances are not high enough to put into the terminal at this
time. SBY may see some 2SM BR vsbys late tonight into early Tue
morning as well.

Outlook: A trough will track across the area late Tue aftn into
Wed morning, bringing a 20-40% chc of showers/tstms. The chc
for showers/tstms lessens Wed, and then increases Thu as a cold
front approaches from the NW. The potential for showers/tstms
could linger into Fri, if the cold front slows down or stalls
over the region.

&&

.MARINE...
As of 300 PM EDT Monday...

No headlines through mid week. S-SW winds will remain below 15 kt.
Waves 1-2 ft, seas 2-3 ft. A cold front approaches by later in the
week. Pressure gradient is expected to tighten ahead of the front
beginning later on Wednesday into Thursday. At this point winds
appear to stay below SCA but will be examined closely over the
coming days. Waves will still be about 1-2 ft but should see a
slight increase in seas to 2-4 ft. Models suggest the front should
clear the area on Friday which will result in a wind shift to a
northerly component.

&&

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

&&

$$
SYNOPSIS...TMG/MRD
NEAR TERM...MRD
SHORT TERM...AJZ/MRD
LONG TERM...ERI
AVIATION...TMG/MRD
MARINE...CMF