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167
FXUS61 KAKQ 201849
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
249 PM EDT Fri Sep 20 2024

.SYNOPSIS...
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High pressure looks to linger across the Southeast with a series of
shortwaves passing through our area ahead of a developing area of
low pressure. Off and on rain chances will persist through the
forecast period. Cooler temperatures are expected to start next
week.
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&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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As of 245 PM EDT Friday...

Key Messages:

- Patchy fog possible overnight.

A low pressure system remains situated off the Northeast coast this
afternoon. A potent area of high pressure is centered over southern
Texas and extends out towards the Gulf Coast states. Standard
afternoon cumulus clouds have developed over our CWA, creating
passing partly cloudy to mostly cloudy skies for the remainder of
the daytime hours. Most, if not all, of the local area will be dry
today, though can`t totally rule out an isolated shower across NE
NC. Otherwise, another round of patchy fog is expected tonight as
skies become mostly clear and winds go calm. Low temperatures will
bottom out around 60 degrees away from the coast.
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&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
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As of 245 PM EDT Friday...

Key Messages:

- Showers and storms expected Saturday evening into the overnight
hours.

- Becoming mostly dry and cooler to start the new week.

The ridge of high pressure will move a bit eastward along the Gulf
Coast this weekend while weakening. Shortwaves will ride along the
northern edge of the ridge into our neck of the woods. The first is
expected to move in later Saturday afternoon with increasing rain
and storm chances. Hi-res model guidance continues to keep the best
chances of rain/storms along and west of I-95 Saturday evening into
the early overnight hours. The Storm Prediction Center does have our
northwest CWA corner in a Marginal Risk for severe weather on
Saturday. The primary threat would be localized gusty winds,
especially where more daytime heating occurs and the storms move in
first. The HRRR tries to have a second round of activity move down
from the north during the early morning hours of Sunday and affect
areas east of I-95, but the NAM Nest and RAP aren`t as excited about
it. Did include a slight chance of rain for coastal locations
before sunrise on Sunday. Kept PoPs low for Sunday evening
aside from isolated showers across NE NC as we should
temporarily dry out.

Moisture lingers along the top of the ridge ahead of another
shortwave on Monday. The shortwave doesn`t move much through the
day, so any rain chances will likely be focused across the far
western edge of the CWA. High temperatures will be in the lower 80s
on Saturday, then cooling into the mid 70s by Monday.
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&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
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As of 245 PM EDT Friday...

Key Messages:

- Low-end precipitation chances linger.

The area of high pressure looks to be traversing the far southeast
coast on Tuesday before sliding just offshore midweek. An initial
shortwave will cross the middle Mississippi River valley on Tuesday
before ejecting into the Great Lakes ahead of a developing cut-off
low further west. Here locally, we will be in southwesterly flow in
between the high pressure and low pressure, allowing moisture to
continue to slide in around the edge of the ridge. Rain chances
will try to nudge back in on Tuesday, but may get held up to
the western corner of the CWA depending on the position of the
high. Beyond that, models disagree on the position of the broad
area of low pressure, thus confidence in the forecast for
midweek and after is low. Generally, would expect low-end rain
chances to persist for now. Temperatures will gradually warm a
bit as thicknesses rise with the ridge pushing up the coastline.
Highs are forecast to be in the upper 70s to around 80 degrees.
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&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
As of 130 PM EDT Friday...

Standard afternoon SCT-BKN040-060 CU has developed for most of the
area. Expect that to dissipate closer to sunset as we lose the
daytime heating. Could see another round of fog overnight resulting
in patchy IFR conditions near terminals. Kept it as a mention of 3SM
at RIC and PHF for now where confidence is a little higher, but
would expect lower VIS and possibly more terminals to be included in
the impacts with the next TAF issuance. Conditions improve after
12-14z Saturday. Winds are generally E/NE at 5-10kt this
afternoon, then becoming 5kt or less tonight.

Generally VFR conditions expected for most of the day on
Saturday, however, rain and storm chances return to western
locations later in the afternoon and evening hours after this
TAF period ends.

Outlook: Rain and storm chances expected during the evening
hours of Saturday, potentially impacting terminals with lower
VIS. Best chances as of now are for RIC and points west.
Activity may linger into the overnight period. Coastal spots
could see showers to start Sunday.

&&

.MARINE...
As of 430 AM EDT Friday...

Key Messages:

- Small Craft Advisories have been issued for all coastal waters
  from later today extended through Sunday.

- Additional Small Craft Advisories may be needed in the
  Bay/lower James later this weekend.

- Winds increase Sunday with persistent long period swells
  keeping seas elevated into the middle of next week.

Sfc low pressure (~1003mb) lingers well off the NJ coast, with
high pressure centered across New Foundland/Labrador. The
stronger pressure gradient remains offshore today, with NW winds
shifting to the NE later today, but remaining in the 10-15kt
range (or less). Seas build to 4-5 ft N later this morning,
eventually spreading S by late aftn/evening. Have added SCAs for
the coastal waters S of Parramore down to NE NC so all coastal
waters are now under headlines.

The latest model trends are a bit slower and weaker with respect
to the sfc high building S into the local waters this weekend.
There is still a decent surge of NE winds expected on Sunday,
but winds may be too marginal for headlines outside of the
lower Bay/mouth of the Bay. Winds over coastal waters look to be
15-20 kt with gusts to 25kt. Building swell combined with
elevated winds should allow seas to build to 5-7 ft in the N and
4-6 ft S Sunday-Monday. A slow improvement is expected Tue-
Wed, though SCAs for seas are still probable through midweek
given the long period easterly swell.

&&

.TIDES/COASTAL FLOODING...
As of 645 AM EDT Friday...

Tidal departures are fairly uniform across the entire area,
generally from +1.0 to +1.5 ft above astro tide levels. With
rather high astro tides given the full moon cycle as well as the
typical higher autumn tides, these departures have been enough
to lead to widespread minor flooding over the past few days.
Over the next 24-48 hrs, the onshore flow will persist with sfc
low pressure lingering well offshore and high pressure over
eastern Canada nosing a bit to the south into the weekend.
Indications are for tidal departures to increase into the +1.5
to up to +2.0 ft range by later Saturday through Sunday
(potentially continuing through the middle of next week). It is
still a bit uncertain, but there is enough confidence at seeing
moderate flooding into the mid/upper Bay as well as Va Beach and
Currituck NC by later Saturday to issue a Coastal Flood Watch
w/ this package. Subsequent shifts may need to extend this out
through Sunday since that will likely be at least comparable if
not slightly higher than what occurs Saturday aftn/evening. It
will also be close to moderate flooding at a few sites on the
VA eastern shore. Have held off on any Watches in these areas
for now, but have extended Coastal Flood Advisories through at
least Saturday aftn for all remaining zones.

In addition, a High rip current risk is in effect today and will
be in effect Saturday as well.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
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MD...Coastal Flood Advisory until 10 AM EDT Saturday for MDZ021>023.
     Coastal Flood Watch from Saturday afternoon through Sunday
     evening for MDZ021>023.
     Coastal Flood Advisory until 4 PM EDT Sunday for MDZ024-025.
NC...Coastal Flood Advisory until 6 AM EDT Saturday for NCZ102.
     Coastal Flood Watch from Saturday morning through Sunday
     afternoon for NCZ102.
VA...Coastal Flood Advisory until 6 AM EDT Saturday for VAZ076-078-
     085-098-521-522.
     Coastal Flood Watch from Saturday morning through Sunday
     afternoon for VAZ098.
     Coastal Flood Advisory until 8 AM EDT Saturday for VAZ075-077.
     Coastal Flood Watch from Saturday afternoon through Sunday
     evening for VAZ075-077.
     Coastal Flood Watch from Saturday morning through Sunday
     evening for VAZ076-078-085-099-100-521-522.
     Coastal Flood Advisory until 6 PM EDT Saturday for VAZ083-084-
     086-089-090-093-095>097-518-520-523>525.
     Coastal Flood Watch from Sunday morning through Sunday
     afternoon for VAZ084-523>525.
     Coastal Flood Watch from Sunday morning through Sunday evening
     for VAZ089-090-093-095>097.
     Coastal Flood Advisory until 5 AM EDT Saturday for VAZ099-100.
MARINE...Small Craft Advisory until 6 PM EDT Sunday for ANZ650-652.
     Small Craft Advisory until 6 PM EDT Sunday for ANZ654-656-658.
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&&

$$

SYNOPSIS...JKP
NEAR TERM...JKP
SHORT TERM...JKP
LONG TERM...JKP
AVIATION...JKP
MARINE...LKB/MAM
TIDES/COASTAL FLOODING...LKB