va discuss
Office: AKQ
FXUS61 KAKQ 191112
AFDAKQ
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
712 AM EDT Fri Apr 19 2024
.SYNOPSIS...
Weak high pressure centered over New England early this morning,
will shift off the coast during today. A cold front will move
across the region late tonight into Saturday morning. Low
pressure will track from the southeast coast, east northeast
and out to sea Sunday into Monday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 400 AM EDT Friday...
Early this morning, weak high pressure was centered over New
England, while weak low pressure was located well off the VA
coast. Also, low pressure was over wrn OH with a cold front
extending from the low swrd through KY and TN. Onshore flow from
the combination of the high and low to our NE or E, was bringing
low level moisture and lots of stratus into the region. Temps
were ranging from the upper 40s to the upper 50s.
The high and low to our NE and E will shift farther E and out to
sea today through tonight, allowing the low to our NW to pull a
cold front twd and across the area today through tonight. A
backdoor front that is south of the area early this morning,
will try to retreat back to the north during today, as the cold
front approaches. The high temp forecast will largely depend on
how fast that front retreats (and also how quickly the low
stratus burns off). Have continued to trend the forecast cooler
(esply near the immediate Atlc coast and on the Eastern Shore),
where temps likely won't get above the upper 50s to mid 60s.
Still think it warms well into the mid to upper 70s across
interior srn VA and NE NC. The greatest amount of uncertainty
with respect to temps today remains near the RIC Metro/I-64
Corridor (where model solutions still range from the 60s to
lower 70s).
Rain chances will return this aftn. Rain will be sctd at first
before increasing in coverage a bit more after 800 pm this
evening into Sat morning. Any chances for tstms will likely be
focused across the west/southwest portion of the CWA since the
backdoor cold front will be retreating across the east, though
still cannot rule out a stray rumble of thunder farther north
this evening into Sat morning, due to increasing elevated
instability. There is a low-end, marginal threat for severe
storms across far SW portions of the area (Mecklenburg County),
but again this will depend on how far north the front can
retreat. Damaging wind gusts would be the main threat with any
stronger storms. This is not looking like a major rain event,
or even moderate rain for that matter. QPF forecasts are still
showing barely .10-.25" in a few spots, though that may even be
a stretch. Lows tonight will range through the 50s.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 400 AM EDT Friday...
The front likely moves ESE of the FA by the middle of Sat morning,
and isolated to perhaps sctd showers (isolated tstm) will likely
linger over ESE portions of the region through late Sat morning
into early Sat aftn. We should see at least partial clearing
over the NW 1/3 to 1/2 of the area by Sat aftn, as drier air
filters in behind the front. As of now, forecast highs Sat will
be in the upper 60s to mid 70s.
A stronger shot of CAA arrives Sat night into Sun morning. Low
temps will drop into the 40s to around 50. Sun through Sun night,
a southern stream low pressure system is progged to move out of
the Gulf Coast states and off the SE coast. This means that rain
chances will return, likely by Sun aftn across the southern
half of the forecast area. Temps will likely be cooler across
southern portions of the forecast area (due to clouds and
increasing rain chances), with highs only in the lower 60s
(potentially even upper 50s in spots). The northern 2/3rds of
the forecast area will see highs in the lower to mid 60s (cooler
across the Eastern Shore). Rain chances will continue over the
srn/SE counties Sun evening into early Mon morning. Lows will
range through the 40s to near 50.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 415 AM EDT Friday...
Any lingering rain will end over extrm SE counties Mon morning,
as the low tracks farther out to sea. Under a partly to mostly
sunny sky, high temps Mon will range through the 60s (warmest
central and wrn counties). High pressure briefly builds over
the area, then slides offshore during Tue, before another cold
front brings shower chances to the region Wed into Wed evening.
Although it will be very cool Tue morning (upper 30s to upper
40s), temps should rebound nicely into the mid 60s to lower 70s.
The cold front will push out to sea Wed night, with high
pressure building into/over the area for Thu. Highs in the
upper 60s to mid 70s Wed. Lows Wed night in the upper 30s to
upper 40s. Highs on Thu mainly in the lower to mid 60s.
&&
.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
As of 700 AM EDT Friday...
Onshore flow was bringing low level moisture into the region
early this morning, resulting in IFR and low MVFR CIGs at the
TAF sites. IFR/LIFR CIGs will linger through this morning,
before improving to MVFR by late this morning or early this
aftn. Clouds will then linger through the day today with
VFR/MVFR CIGs. Finally, sctd showers (maybe isolated tstms) move
in from W to E for late this aftn into Sat morning.
Outlook: Rain chances generally end after Sat morning, but
return later Sun into early Mon, as low pressure tracks from
the southeast coast, east northeast and out to sea Sun into
Mon.
&&
.MARINE...
As of 330 AM EDT Friday...
Latest analysis shows a backdoor cold front now well south of
the local waters. Surge of E-NE winds has gradually weakened, as
high pressure builds south from the northern Mid-Atlantic. Will
allow SCA over the lower bay to expire at 08z. SCAs remain in
effect into at least late this morning with choppy E-NE wind
wave lingering into midday across the northern and central
coastal waters, with significant seas slightly lower (3-4 ft) to
the south of the VA/NC border. E-NE winds ~10-15 kt veer to the
E-SE this afternoon ahead of another cold front which drops
across the region late tonight (Fri night) into Saturday morning.
Winds veer around to the NNW post frontal Sat morning, but
should be mainly sub-SCA given weak cool-air advection. Winds
remain onshore ~10 kt over the waters Sat aftn and evening, as
a weak coastal trough/coastal front remains over the area. WNW
winds do increase Sat night into Sunday, but look to remain
sub- SCA at this time, with deepening low pressure along the
front nudging it farther E-SE and offshore. Meanwhile, 1022+mb
high pressure builds in from the west. Waves mainly 1-2 ft this
weekend, seas 2-3 ft north, 3-4 ft south. Would not be surprised
to eventually (briefly) need SCA over southern coastal waters
south of Cape Charles by the time we get into the day on Monday,
but will keep just below for now.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ650-
652.
Small Craft Advisory until 10 AM EDT this morning for ANZ654-
656.
&&
$$
SYNOPSIS...TMG
NEAR TERM...TMG
SHORT TERM...AJB/TMG
LONG TERM...AJB/TMG
AVIATION...TMG
MARINE...AM/MAM
Office: RNK
FXUS61 KRNK 191528
AFDRNK
Area Forecast Discussion
National Weather Service Blacksburg VA
1128 AM EDT Fri Apr 19 2024
.SYNOPSIS...
A cold front will move east across our area today, exiting to
the coast tonight. Temperatures will return to a more seasonal
levels this weekend. A front over the southeast could keep
chance of showers across southern Virginia into North Carolina
Sunday, before high pressure nudges in Monday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 1050 AM EDT Friday...
Key Messages:
1) Low clouds in the Piedmont through early afternoon
2) Showers/scattered storms today. Marginal risk of severe storms
especially along/south of the VA/NC border this afternoon.
Tracking area of showers with embedded thunderstorms crossing
I-77 corridor. This appears to be associated with mid-upper
level vorticity which can be seen per water vapor imagery.
Activity has been producing about 1-2 tenths of an inch of rain.
Models weaken this area precip as it nears the Blue Ridge,
encountering a stable easterly wind. Shallow wedge of marine air
extends from Blue Ridge all the way to the coast associated
with low level stratus. This wedge generally defines a surface warm
front which extends from ROA-GSO with east winds over the
piedmont and southwest winds through the NRV over to about the
Blue Ridge. With afternoon heating would think low stratus and
stable will erode but not confident it will be quick enough for
any substantial build-up of CAPE.
In general...lots of cloud cover inhibiting solar insolation,
but do think opportunity for sunny breaks to provide for some
increasing instability mid-late afternoon, esp along and south
of the VA/NC border. Latest convective allowing models suggest
best chance for shower/storm redevelopment to occur over the NC
foothills and piedmont with marginal risk for severe
storms...wind and hail being the primary threat. Even with the
CAMS, not a high confidence forecast as models are varying on
coverage of storms.
A cold front extends from PIT-BNA. This front will cross the
area this evening, introducing lower dewpoints and cooler
temperatures for tonight and Saturday. Shower chances may linger
until about midnight, then wane thereafter. Skies likely to
stay fairly cloudy most of the night with some clearing toward
dawn. Variations exist in the models with respect to cloud
cover late tonight so low confidence in tonight's sky
conditions and temperature. More cloud cover will keep lows
elevated and cooler if skies clear. For now went close to MOS
with mid to upper 40s west to mid 50s east.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
As of 145 AM EDT Friday...
Key Messages:
1. Near normal temperatures, cooler on Sunday.
2. Precipitation chances increase Sunday south of VA border.
3. Dry weather on Monday.
By the start of the weekend, the cold front that will have crossed
the area Friday will be situated along the Atlantic Coast, and
extending into the southeastern US. The front will stall along the
Gulf Coast states, leading to rain for most of the weekend for that
area. The upper low associated with this front will track
northeastward through Saturday, pulling the cold front away from the
coast. As the front shifts farther east, low pressure
strengthens some and the precipitation may reach as far north
as the VA/NC border by Sunday. However, with a surface high
pushing into the area from the west, the highest probabilities
for precipitation stay farther south. The surface high will
expand eastward, and become centered over the Ohio and Tennessee
Valleys by Monday, keeping the central Appalachians dry for the
start of the work week.
The 500mb flow will become more zonal through the weekend, but
turning more northwesterly over the area by the beginning of the
week, as the upper trough lifts farther away. This, and the surface
high, will lead to a few days of cooler temperatures, although they
will be closer to seasonal normals. Sunday looks to be the coolest
day of this forecast period, as the colder air fills in behind the
front.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
As of 200 AM EDT Friday...
Key Messages:
1. Increasing temperatures Tuesday.
2. Another chance for rain on Wednesday, highest chances in the
mountains.
3. Dry weather returns for Thursday.
The surface high pressure that will have kept the area dry through
Monday will shift southeast, but still keeping the area mostly dry
through Tuesday. A surface low pressure system will track across the
northern tier of the US through the beginning of the work week,
while its cold front reaches from the upper Midwest into the central
Plains by Tuesday. This will advance towards the east, crossing the
Appalachians by Wednesday. This will be the next chance for
precipitation for the area, with the highest chances in the
mountains late Tuesday into Wednesday. The 500mb trough associated
with this surface front will stay well to the north of the area,
along with the better upper dynamics, which will limit the coverage
of precipitation over the area.
Southwesterly flow ahead of the cold front will bump temperatures up
to above normal on Tuesday. After the frontal passage Wednesday,
high pressure pushes southward back into the area, which will bring
dry conditions back, but also drop temperatures below normal for the
second half of the work week.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
As of 639 AM EDT Friday...
Key Messages:
1). MVFR, possible IFR east of the Blue Ridge through 14z.
2). Decaying area of precipitation with MVFR ceilings spread
into the western parts of the CWA after 12Z.
3). Scattered showers/thunderstorms potentially redevelop along
frontal boundary mid-late Friday afternoon, but low confidence
on coverage east of WV.
High clouds working in from convective blowoff over the Ohio
Valley. Low clouds on easterly flow advancing westward toward
LYH/DAN and will likely see some MVFR, possible IFR at LYH/DAN
in the 12-16z time frame, and even ROA may be getting this.
Area of convection over KY appears to weaken as it moves toward
our mountains this morning, so am keeping showers out except
BLF, as thinking coverage may not be as great east of here. Will
mainly have VCSH in the west this morning except BLF where MVFR
cigs/vsbys are likely in the 11-17z time frame.
By late morning into the afternoon, storms will be scattered
around so have VCTS everywhere except LYH/DAN where think
coverage is more widely scattered later in the day.
Looking at mainly dry after 00z with VFR returning for most,
except holding on to lower MVFR cigs at BLF, possibly LWB.
Appears skies clear out late in the west and parts of the east
though confidence is low.
Winds today will be turning more south to southwest ahead of the
front, then west-northwest behind it Friday evening.
Extended Aviation Outlook...
The aforementioned cold front will exit to the south and east
of the CWA by Saturday. Some MVFR ceilings may linger across the
mountains Saturday morning. North winds will provide some
clearing for late Saturday, but more moisture may surge
northeastward during Sunday and Monday to bring another chance
of rain as low pressure rides across the southeastern states.
Confidence in the later scenario is quite low at this time.
Another front approaches by middle of next week though shower
chances and sub-VFR are not expected to be that great.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...PM/WP
NEAR TERM...PM
SHORT TERM...AS
LONG TERM...AS
AVIATION...RAB/WP
Office: LWX
FXUS61 KLWX 191423
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1023 AM EDT Fri Apr 19 2024
.SYNOPSIS...
Low pressure will track well to our north today, causing a cold
front to move through late tonight. High pressure will gradually
build in from the west this weekend into early next week while
waves of low pressure pass well to the south. The next cold
front will reach the area Wednesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Mid-morning update: No major changes were made to the previous
forecast. Previous discussion follows...
Onshore flow between low pressure east of the Delmarva and high
pressure over New England has been advecting marine stratus
westward overnight. These clouds will be most prevalent east of
the Blue Ridge through the morning, with some spilling west into
the northern Shenandoah Valley. Although the low clouds may mix
out toward midday as winds take on a more southerly component,
additional clouds will have advected over the area ahead of the
next weather system.
That cold front will slowly approach from the Ohio Valley
through the day. Shower chances will gradually increase west of
the Blue Ridge through the morning, but it appears doubtful more
than spotty light showers will advance east of the Blue Ridge
into the afternoon. As weak instability increases, a few
thunderstorms are also possible this afternoon west of I-81. The
duration of low clouds will impact temperatures today, with
areas near/northeast of the Potomac remaining in the lower to
mid 60s. Some spots in central Virginia and the valleys west of
the Blue Ridge could top 70 with enough cloud breaks.
The cold front will continue eastward tonight accompanied by
scattered showers. With weak forcing and a downsloping wind
component aloft, it appears showers will have difficulty holding
together, and have capped PoPs at 50 percent or less east of the
Blue Ridge. A stray thunderstorm could cross southern Maryland
with some weak elevated instability, but an overall poor
convective environment should preclude thunder across much of
the area. Some patchy fog could develop with light winds
overnight, but this is less certain. Cooler air begins entering
western areas late, with lows near 40 in the higher elevations,
increasing to the mid 50s to the south and east.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
WNW winds will become gusty behind the front on Sunday, with
gusts of 20-30 mph common. Clearing skies and the downsloping
winds will result in warm temperatures ranging from the mid 60s
to mid 70s in the lower elevations. High level clouds begin to
increase Saturday night with lows from the upper 30s to mid 40s.
The higher Alleghenies will likely fall below freezing.
Low pressure will pass well south of the area Sunday along the
stalled front. High pressure extending eastward from the Plains
will likely keep the area dry, although there is still a 20
percent chance some light rain could reach Nelson to St. Marys
Counties should a northern solution verify. Even though it will
be dry, mid and high level clouds will be prevalent through the
day. These clouds will clear to the east Sunday night, and winds
should be fairly light. This will result in a chilly night with
lows ranging from the mid 30s to mid 40s. With dew points in the
upper 20s and lower 30s, some frost can't be ruled out in rural
valleys, especially west of the Blue Ridge.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
To start off the work week, the hemispheric pattern features a split
flow regime. An expansive longwave trough extending into the high
latitudes will pull away from the northeastern U.S. At the same
time, a weak shortwave in the southern stream is expected to remain
suppressed with no direct influence on the local weather. Eventually
the height falls with this system will induce cyclogenesis off the
southeastern U.S. coast on Monday evening. Ensembles agree on
carrying this area of low pressure well out to sea as high pressure
briefly settles over the southern/central Appalachians on Tuesday
morning. Farther upstream, the next weather maker looms across the
Upper Great Lakes. The associated cold front is likely to cross the
Mid-Atlantic region early Wednesday. The progressive nature of this
system should limit total rainfall amounts. In the wake, a gusty
northwesterly wind is expected through the remainder of the day. The
current forecast package calls for gusts around 20 to 25 mph,
locally a bit higher in the terrain. High pressure returns on
Thursday into Friday which will favor a return to dry weather.
Fairly seasonable temperatures are expected through mid-week with
highs in the mid 60s to low 70s, with 50s across the mountains.
Behind the front, cold advection will help lower temperatures back
down into the upper 50s to mid 60s by Thursday. Regarding overnight
conditions, only Tuesday night appears mild given the warm advection
pattern. Otherwise, multiple nights see low temperatures falling
into the mid/upper 30s which could bring some frost concerns where
the growing season has commenced (everywhere outside the
Alleghenies). For the Allegheny mountain range, lows push near to
below freezing at times through Thursday night.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
Onshore winds have advected marine stratus into the area this
morning. So far these clouds have been primarily very low-end
MVFR, but IFR conditions are ongoing at CHO. These clouds will
likely lift by this afternoon as winds take on a more southerly
component. However, the timing is uncertain, as well as if and
how long some locations may lift into VFR.
A cold front will progress into the area late this afternoon and
tonight. Showers ahead of the front appear scattered at best,
with a slightly better chance at MRB. The showers will be light
in nature and thunderstorms are unlikely. MVFR conditions likely
return this evening as winds will be light near the front, and
IFR can't be ruled out. A drying NW wind will arrive late
tonight and scour out lower clouds.
WNW wind gusts of 20-25 kt are likely behind the front on
Saturday with VFR conditions. Low pressure will pass well to the
south between Saturday night and Sunday night, with any ceilings
mid/high level in nature. W to NW winds will generally be 5-10
kt through this period.
VFR conditions are expected on both Monday and Tuesday. The forecast
should be dry as high pressure largely remains in charge.
Northwesterly winds on Monday will eventually give way to southerly
flow Monday evening into Tuesday. Afternoon winds on Tuesday may
gust up to 20 knots.
&&
.MARINE...
Light onshore flow is present this morning. As winds take on a
more southeasterly component this afternoon and evening,
marginal Small Craft Advisory conditions are expected south of
the Bay Bridge and the Potomac below Dahlgren. A cold front will
cross over the waters tonight, causing winds to turn out of the
northwest. Small Craft Advisory conditions appear likely in
northwesterly Saturday and Saturday night, although there may be
three stages: an initial surge down the waters behind the front
early Saturday morning, diurnal mixing across the northern bay
and upper Potomac through the afternoon, then another surge down
the waters Saturday night.
Winds should be lighter Sunday and Sunday night with low
pressure passing well to the south and high pressure building in
from the west. However, a few 18 kt gusts can't be ruled out
during periods of pressure rises.
Winds over the marine waters remain below advisory levels on Monday.
Winds shift from northwesterly to southerly by late Monday.
Southerly flow on Tuesday likely brings gusts up to 20 knots which
suggests Small Craft Advisories may be needed.
&&
.TIDES/COASTAL FLOODING...
Tidal anomalies have drastically increased this morning, causing
water levels to rise rapidly. Coastal Flood Advisories are in
effect during the upcoming tidal cycle for DC/Alexandria, King
George/Charles, St. Mary's, Calvert, and Anne Arundel Counties.
Annapolis may come close to Moderate flood stage with the
upcoming tide cycle as well. Water levels will likely remain
elevated through the tide cycle tonight as well, and additional
headlines may be needed. Anomalies should finally start to
decrease late tonight into tomorrow as winds turn northerly and
then eventually northwesterly, allowing water to drain out of
the Bay.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory from 3 PM this afternoon to 9 PM EDT
this evening for DCZ001.
MD...Coastal Flood Advisory until 8 AM EDT Saturday for MDZ014.
Coastal Flood Advisory until 4 PM EDT this afternoon for
MDZ016-018.
Coastal Flood Advisory until 4 AM EDT Saturday for MDZ017.
VA...Coastal Flood Advisory from 3 PM this afternoon to 9 PM EDT
this evening for VAZ054.
Coastal Flood Advisory until 4 PM EDT this afternoon for
VAZ057.
WV...None.
MARINE...Small Craft Advisory from 3 PM this afternoon to midnight EDT
tonight for ANZ532>534-537-541-543.
&&
$$
SYNOPSIS...ADS
NEAR TERM...ADS/KJP
SHORT TERM...ADS
LONG TERM...BRO
AVIATION...ADS/BRO/KJP
MARINE...ADS/BRO
TIDES/COASTAL FLOODING...KJP
