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000
FXUS61 KAKQ 131120
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
620 AM EST Thu Dec 13 2018

.SYNOPSIS...
High pressure will prevail over the Mid-Atlantic region through
today. Low pressure approaches from the southwest tonight into
Friday, then tracks across the local area late Fri through
Saturday. An upper level trough will remain over the area
through Sunday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 250 AM EST Thursday...

The local area will remain protected by sfc hi pres invof the
Carolinas as weakening lo pres and its associated sfc trough
pass by to the N. Meanwhile...trough aloft will begin to sharply
amplify invof central/srn Plains w/ lo pres development
occurring over NE TX. Another dry day is expected here...w/
temperatures nudged a little closer to normal. Will maintain
readings remaining blo guidance over the lingering SN cover
inland. Otherwise...BKN-OVC SC-AC nrn areas...CI across the S.
Winds remain light and generally from the S. Highs in the m-u40s
inland to the l-m50s far SE VA-NE NC.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
As of 250 AM EST Thursday...

Lo pres will be making steady progress E into the lower MS
Valley tonight-Fri while hi pres shifts off the E coast.
Models...w/ the GFS oddly leading the way showing in-situ CAD
development Fri over interior VA as coastal front moves inland
along the coastal Carolinas. Deeper layered moisture will be
overspreading the FA on Fri...w/ highest PROB for RA mid-late
morning W then increasing to the E through the afternoon. The
increase in moisture will aid in snow melt inland...as well as
keep temperatures blo guidance. Also...there will be a concern
for FG w/ the warmer/moist air over the linger SN cover. Highs
Lows tonight in the l-m30s...except near 40F right at the coast
in SE VA-NE NC. Highs Fri in the l-m40s central/W to the m50s-
around 60F E and SE.

Widespread RA expected Fri night into early Sat as lo pres
tracks into the TN Valley...pushing an occluded closer to the
FA. RA from late Fri through Fri night may be heavy at times.
Highest QPF right now is expected to be in SE VA-NE NC (away
from the melting SN). Will be holding off on any Flood
Watch...keeping mention of locally +RA and possible (urban and
eventually minor river) flooding in HWO. Steady or rising
temperatures Fri night w/ potential for areas of FG (both on
land and water) as dew points rise.

Models showing nebulous sfc pres pattern over the FA Sat...which
suggests keeping conditions cloudy though PoPs likely lower.
Highs in the u40s-l50s W to the l-m60s SE VA-NE NC.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 355 PM EST Wednesday...

Still some model differences in the long term, but it is appearing
likely that showers will linger into at least Sunday afternoon. Both
12Z ECM and Canadian have the upper level low pressure system moving
further to the south (over North Carolina) while the 12Z GFS brings
this low pressure further north over Virginia. FV3 also agrees with
the ECM/Canadian on general low placement, but is drier compared to
the other models. Have trended towards the more southern placement
of the upper level low, thus have trended PoPs upward during the day
Sunday. Both the ECM and Canadian show surface cyclogenesis off the
NC coast late Sunday into Monday, allowing for the threat for rain
to continue across the east into overnight Sunday. Through this
period, the ECM is the most aggressive with QPF, showing an
additional 1.00" plus of precipitation for portions of the region
while the American models are much drier during this timeframe.
Temperatures on Sunday will range from the upper 40s NW to the
mid/upper 50s further SE. Low temperatures will range from the
low/mid 30s to the lower 40s.

By Monday afternoon, high pressure returns to the area bringing dry
weather for the remainder of the long term period. Temperatures will
trend cooler by Monday with high in the lower 50s on Monday and only
mid to upper 40s for Tuesday. Overnight lows will range from the 30s
to upper 20s.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
As of 620 AM EST Thursday...

VFR conditions through the 12Z TAF forecast period. BKN high
level clouds mixed w/ SCT-BKN SC/AC. SSE winds aob 5 KTS. Lo
pres approaches from the SW Fri and moves across the area Fri
night into Sat bringing widespread RA and degraded flight
conditions. An upper level trough lingers over the area into
Sun.

&&

.MARINE...
As of 330 AM EST Thursday...

With sfc high pressure centered over New England w/ associated sfc
ridging extending SSW to the NC/SC coast, winds are out of the S at
5-10 kt over the waters early this morning. Tranquil marine
conditions will remain in place through late tonight as high
pressure will continue to dominate our local weather. A slow moving
area of low pressure is progged to impact the area late Fri
through this weekend. E/SE winds increase to 10-15 kt during
the day on Fri before briefly increasing to 15-20 kt Fri night
(highest over the ocean) as an area of sfc low pressure
develops across the Carolinas. Winds decrease and become more
variable by Sat PM as the aforementioned sfc low moves offshore
and a secondary sfc low (coupled w/ a closed upper low) moves
over the mountains of VA/WV. Winds then become more N/NW by Sun
aftn/evening (and increase to 15-20 kt as the secondary area of
low pressure moves offshore. Winds turn more to the NW on
Mon/Mon night and remain in the 15-20 kt range (with higher
gusts) to start next week behind the departing system. Have
advertised 5-7 ft seas starting Friday night with seas remaining
elevated through the weekend and perhaps even Monday as NW
winds increase. Therefore, SCAs will likely needed for the
ocean zones starting Friday night. Winds remain below SCA levels
for the most part this weekend. However, cannot rule out a
brief period of ~20 kt gusts over the southern Chesapeake Bay
(in addition to isolated gusts to 25 kt over the ocean) Fri
night.

&&

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

&&

$$
SYNOPSIS...MAM
NEAR TERM...ALB
SHORT TERM...ALB
LONG TERM...AJB
AVIATION...ALB/MPR
MARINE...ERI