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153
FXUS61 KAKQ 221534
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1034 AM EST Tue Jan 22 2019

.SYNOPSIS...
Arctic high pressure moves off the coast this evening. A series
of low pressure systems will track northeast along the mountains
Wednesday and Thursday. The associated warm front lifts north
of the area Wednesday with the trailing cold front crossing the
region late Thursday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 1030 AM EST Tuesday...

Going forecast looks good. Still chilly as of 10am with most
places in the 20s. Expect a rebound into the low-mid 30s north
and mid-upr 30s south under sunny skies.

As of 200 AM EST Tuesday...

Ridge axis overhead this morning slowly pushes to the coast by 00Z.
After a frigid start, temps begin to moderate a bit under mstly
sunny skies. Highs low-mid 30s north, mid-upr 30s south.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
As of 200 AM EST Tuesday...

Sfc high remains near the coast this evening then pushes farther
offshore after midnite. Despite an increase in high clouds, temps
quickly drop back into the 20s after sunset. Clouds continue to
increase/thicken ahead of the next system apprchg from the west
after midnite. Temps then steady out or begin to slowly rise into
the upr 20s to lwr 30s late.

Models differ on some vry light upslope moisture progged to move ne
across the Piedmont arnd 12Z Wed. Oddly, the GFS is dry while the
NAM/SREF show some spotty light pcpn dvlpng east of the mts. Given
temps arnd 32, thermal profiles suggest this pcpn falls as lgt fz
rain/fz drizzle for an hour or two arnd 12Z Wed from about CXE-FVX-
LKU. Will carry this in the grids attm but no headlines anticipated
given low confidence this will actually occur.

Otw, a warm front lifts north across the local area Wed. Models now
backing off on the amount and coverage of pcpn Wed. Expect most areas
to stay dry except for wrn/nrn most zones where 20-30 PoP will be
kept. Much warmer with temps ranging from arnd 50 nw to lwr 60s sern
coastal areas.

Strong southerly flow Wed night into early Thu will keep mins warm
Wed night before the arrival of the more widespread rain after midnight.
Lows 45-50 north/west to low-mid 50s se. Low pressure tracks across
the area late Wed nite and Thu morning before exiting off the coast
Thu aftrn. Strong lift and srn stream moisture noted for periods of
mdt to lclly hvy rainfall for about a 6-8 hr period at any given
location (generally west of I-95 prior to 12Z/Thu and along/east
of I-95 from 12-18Z/Thu). QPF amounts will avg 0.75" to 1.25".
Models also differ on just how fast the moisture exits Thu aftrn.
For now will split the difference and go with pcpn tapering off
to some light rain or sct shwrs late Thu. Highs Thu in the 50s
except lwr 60s se. Any lingering rain exits the coast Thu eve
behind the systm. Decreasing clouds/colder. Lows mid 20s-mid
30s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 230 AM EST Tuesday...

A secondary, dry cold front crosses the region during the day Friday.
Am not expecting much in the way of PoPs with this system. Highs
only make it up into the 40s Friday afternoon with temperatures
dropping into the upper teens to 20s across the region for Friday
night. Dry and cool conditions will persist for the first half
of the weekend as high pressure remains in control during this
time period.

22/00Z runs of both the GFS/ECMWF have backed off on the threat
for a storm system late in the weekend across the area. Adjusted
the grids a bit but did keep slght chc PoPs in to allow later
shifts to drop/raise PoPs as needed based off later model trends.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
As of 615 AM EST Tuesday...

VFR conditions thru the forecast period as high pressure moves off
the coast thie eve. Some high level clouds overspread the area
late with a mid level cloud deck overspreading the Piedmont after
midnite. N aob 10 KTS wind slowly shift to the south later today.

Outlook:
Low pressure and assctd frontal bndrys will affects the area Wed
into Thurs. This system will likely bring more rain and flight
restrictions, especially from 06-18Z/Thu.  High pressure briefly
returns Thursday night, before another cold front/sfc trough crosses
the area on Friday (conditions look to remain VFR Thu night and Fri).

&&

.MARINE...
As of 945 AM EST Tuesday...

Went ahead and extended the SCA until 1 PM for ANZ658 as Buoy
44100 was still reporting ~6 ft seas as of 9 AM. Expect seas to
fall below SCA thresholds this aftn.

Previous Discussion: Conditions are improving across the marine
area early this morning as high pressure builds into the
region. Winds are decreasing from north to south with
northwesterly winds 15-20 knots for the Bay and ocean zones
north of Cape Charles Light with 15-25 knots for points south.
Waves are running 1-3 feet in the Bay with seas 4-7 feet
offshore (highest values near and south of the VA/NC border).
Winds will decrease further today as high pressure settles
overhead.

Winds will swing around to southerly as the high moves offshore late
this evening with generally 10-15 knots expected in the Bay and
offshore. Low pressure to our west will approach the area on
Wednesday. With a tightening pressure gradient, winds will increase
15-20 knots and seas build 3-5 feet offshore with waves in the Bay
increasing to 2-3 feet. The low and its associated cold front will
cross the region late Wednesday and early Thursday. Latest guidance
is suggestive of a period of southerly Gales for the offshore
zones Thursday morning with significant pressure falls and
robust 925mb winds in excess of 50 knots. Will hold off on
issuing a Gale Watch with this package given some model
disagreement and the fact that the threat is 4 periods away.
Winds will become northwesterly behind the front but it appears
significant cold advection will be lacking with this system and
winds should stay near or below SCA thresholds. Seas build 5-9
feet (especially north) early Thursday with 3-4 foot waves
expected in the Bay. Conditions are forecast to improve for the
end of the week as high pressure returns.

&&

.TIDES/COASTAL FLOODING...
As of 945 AM EST Tuesday...

While tidal anomalies are expected to slowly rise throughout
the day, am expecting water levels to fall to between 1 and 1.5
ft below MLLW during the low tide cycle this aftn at
Chincoteague and Oyster. Therefore, went ahead and issued a Low
Water Advisory for the Atlantic coast from Chincoteague to Cape
Charles (valid from 12-5 PM today). Elsewhere, water levels
should remain just above advisory criteria during low tide.

&&

.EQUIPMENT...
As of 1030 AM EST Tuesday...

The KAKQ radar is down due to a pedestal slip ring assembly
failure. Due to the time to procure/ship the needed parts, and
the repair time, the radar will remain down through at least
Friday.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Low Water Advisory until 5 PM EST this afternoon for ANZ652-
     654.
     Small Craft Advisory until 1 PM EST this afternoon for ANZ658.

&&

$$
SYNOPSIS...MPR
NEAR TERM...MPR/MRD
SHORT TERM...MPR
LONG TERM...AJB/MPR
AVIATION...MPR
MARINE...ERI/RHR
TIDES/COASTAL FLOODING...
EQUIPMENT...