Area Forecast Discussion
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FXUS61 KAKQ 272037
Area Forecast Discussion
National Weather Service WAKEFIELD VA
437 PM EDT Mon Mar 27 2017
A cold front approaches from the west tonight and crosses the
region late Tuesday through Tuesday night. High pressure builds
in from the north on Wednesday. The high retreats to the
northeast on Thursday as the next system approaches from the
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Latest analysis indicating main area of sfc low pressure
centered over the lower OH Valley, with a weak sfc trough noted
to the lee of the Appalachians near CHO. Some weak ridging aloft
has generally limited showers/tstms east of the Mtns so far,
while coverage of showers and storms is much greater across
TN/KY/WV. Other than a few remaining spotty light
showers/sprinkles exiting the coast, conditions look to stay
mainly dry through late aftn. With the weak sfc trough progged
to shift ENE through northern VA this evening, and some minimal
ML Capes around 500 J/Kg may see a few isolated showers/tstms
move across interior portions of the CWA so will maintain ~20%
PoPs through 9 pm. Otherwise, partly cloudy and warm with
temperatures mainly holding in the 70s and slowly falling into
the 60s by late evening.
Upper level ridging begins to break down later tonight...as the
mid/upper level trough currently centered over southeast
MO/southern IL pushes east overnight. After a period of mainly
dry conditions, PoPs will ramp back up after 04-06Z as the front
approaches from the W and mid-upper level heights fall along
with some increase in mid level lapse rates between 06-12Z.
Low level instability will be very low, but think there is
enough instability aloft to mention a slight chance for tstms
over roughly the western 1/2 of the CWA after 08Z. Will carry
~40% chc PoPs west of I-95 to 20% to 30% or less farther east
and southeast. Warm with lows mainly 55-60 F. With the moist
boundary layer, GFS is indicating a fair amount of fog, but
given a SSW wind of 5-10 mph and warm temperatures, think this
is overdone and that areas of low clouds are more likely.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
Upper level trough pushes into the area Tue, with a model
consensus pushing the main shortwave energy across southern
VA/and eastern NC from 18-00z. Have raised PoPs to likely (60%)
in the aftn over portions of far southern VA and northeast NC
where deepest lift and moisture look to coincide during peak
heating hours. Maintained mainly high chance PoPs (50%)
elsewhere (except for a small area of likely PoPs across the NW.
Continued warm w/ highs mainly in the mid to upper 70s (could be
around 80 F if enough sunshine develops). There will be some
potential for a few stronger storms Tue aftn/evening as speed
and directional shear increases and sfc dew pts will be around
60F. Overall not looking like widespread severe wx as there is
still some question as to how much storm organization there will
be as latest models are hinting at a lot of clouds and an
earlier arrival of precip by late morning. SPC has area in
marginal risk for severe wx and this seems about right given the
current parameters depicted in the models. Overall, highest
shear values look to reside over NC.
Will linger the chance PoPs through the early evening W and to
around midnight along the coast. Drying after midnight with
lows mainly 50-55 F. Becoming partly/mostly sunny Wed after some
early clouds (especially south) as drier air moves in from the
N. Somewhat cooler but still a little above avg with highs
60-65F near the coast and in the upper 60s to lower 70s well
inland. Upper ridge axis quickly moves back into the region by
Thu, allowing return of mid/high clouds during the day. With
fairly low mixing and overrunning clouds, expect a cooler day
with highs mainly ranging from the upper 50s to the lower 60s.
Kept it dry through 22Z despite the increase in clouds.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Good chc for showers and possible tstms later Thu night into
early Sat morning, as low pressure and another associated cold
front approaches and moves acrs the region. Dry wx and high
pressure returns for Sat aftn thru Sun night. Yet another system
may approach fm the west late Mon.
Highs in the upper 50s to upper 60s Fri, in the 60s to near 70
Sat, in the mid 60s to lower 70s Sun, and in the 60s to near 70
Mon. Lows in the 40s Thu night, in the upper 40s to mid 50s Fri
night, in the 40s Sat night, and in the mid 40s to near 50 Sun
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
Generally VFR ceilings are expected for this afternoon and into
the first half of the night for the forecast area. Only a few
scattered sprinkles are left across eastern parts of the area
this afternoon, rain coverage is not high enough to include in
the TAF. Any sprinkles/light showers should continue to
dissipate through the afternoon. Abundant low level moisture
across the region has allowed for BKN cumulus to develop with
bases around 3500 feet. Any cumulus should diminish after
Skies are expected to become mainly clear for the first half of
the night with only some high clouds. MVFR ceilings and
potentially patchy fog may develop late tonight and into early
tomorrow morning, especially at SBY and RIC, due to the moist
airmass in place. Scattered showers and thunderstorms will be
possible during the day on Tuesday, with the potential for a few
storms to be severe Tuesday late afternoon and evening.
Outlook: Unsettled weather conditions will continue into Tuesday
night due to the potential for showers and thunderstorms. Sub-
VFR conditions will be possible once again Wednesday morning due
to low ceilings and the potential for fog. Dry/VFR conditions
return on Wednesday as winds shift to the north. The next storm
system is expected to approach the area Friday bringing the next
chance of adverse aviation conditions.
No headlines in the short term tonight thru Wed. Late this aftn,
high pressure was well off the Mid Atlc coast while low pressure
was cntrd over srn IL/extrm ern KY. The low and its associated
cold front will approach fm the west tonight into Tue morning,
then move acrs the area and off the coast late Tue/Tue night.
SSW winds generally 10 to 15 kt will continue tonight into Tue
evening, then become NW then N Tue night into Wed morning behind
the front. N winds 10 to 15 kt during Wed, as high pressure
starts to build in fm the N. Do not expect SCA conditions to be
met thru Wed. High pressure will continue to build in fm the N
Wed night into Thu morning, then slides out to sea Thu aftn into
Thu night. NNE winds 15 kt or less Wed night, then NE 5 to 15 kt
Thu aftn. E winds 5 to 10 kt becoming SE Thu night.