Area Forecast Discussion
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FXUS62 KILM 271124
Area Forecast Discussion
National Weather Service Wilmington NC
724 AM EDT Thu Apr 27 2017
High pressure offshore will bring a warming and dry trend late
this week and through the weekend. A weakening and lingering
cold front will bring a slight chance of showers or a
thunderstorm tonight or early Friday. Daily max and min
temperatures today thru the weekend will run 10 to 15 degrees
above normal. A stronger frontal system will bring a chance of
convection late Monday and early Tuesday followed by high
pressure for the middle of next week with temperatures back to
.NEAR TERM /THROUGH TONIGHT/...
As of 330 AM Thursday...Moderately strong warm advection will
push afternoon high temperatures a solid category above
climatology. Most areas away from the immediate marine influence
will heat up into the mid 80s. Moisture too will be on the rise
in the warm advection zone though most of it may remain just to
our west. There are considerable differences regarding not only
the eastern progress of the moisture but also the sense of
timing. The 00Z EC supports the far less agressive WRF but did
raise POPS a bit in deference to the much wetter GFS as well as
to match with neighboring WFOs. Any storms that do make some
progress into western zones this evening will then fizzle out as
they both encounter the ridging offshore and also lose daytime
heating. Again the GFS maintains action through the night mainly
along the coast with a tongue of warm advection and a bit of a
low level jet. Will carry 20 POPS to cover for this possibility.
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
As of 330 AM Wednesday...Models now consistent with stalling the
approaching cold front just west and north of the FA early
Friday. Weak dynamics and avbl instability, models indicating 2k
to 3+k CAPE, will all combine to carry widely scattered showers
or thunderstorms across portions of the FA. Convection will
also occur along the pinned sea breeze boundary by Fri midday
thru the aftn. Fri highs will see widespread 80s with a few 90
degree readings possible inland from the coast.
For Fri night thru Sunday morning, ridging both aloft and at the
sfc will be the primary drivers for sensible wx conditions
across the FA. The building heights 590+ dam and subsidence
overhead will help keep convection to a minimal, if any at all.
The sea breeze will be active in terms of cu development along
it, however any vertical growth of the cu will be suppressed.
Sat highs will see widespread 80s again. With southerly flow in
the lower levels during Sat thru Sat night, the marine
influence will push further inland, also aided by the sea
breeze, and keep 90+ degree readings well inland, ie. along or
west of the I-95 corridor. Summertime readings for min temps can
be expected with mid to upper 60s to around 70 at the coast
where latest SSTs are in the 70s now.
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 300 PM Wednesday...Surface and mid level high pressure
just off the east coast will maintain deep southerly flow on
Sunday. However, subsidence on the periphery of the ridge aloft
should keep diurnal convection to a minimum. Cannot rule out an
isolated sea breeze shower but any activity would be short lived
and very isolated. Temperatures will be above to well above
Surface and mid level ridge start to weaken and drift east Mon,
allowing a cold front into the region. Front moves across the area
Mon night, likely accompanied by some convection. Although the
parent low will be over the Great Lakes (along with the bulk of the
dynamics) there are still at least a few signals pointing to some
potential for strong/severe storms ahead of the front. Strong low
level jet will be in place along with modest divergence aloft and
potential for PVA as shortwaves rotate around the base of the
trough. Confidence is low at this point as timing and instability
remain in question but is something to keep an eye on.
Front moves off the coast early Tue with high pressure building in
from the west during the day then shifting overhead Tue night before
moving offshore Wed. Flow aloft will remain west to southwest Tue
and Wed as dry air and subsidence help dry the region out with
temperatures running near climo.
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
As of 12Z...Mainly VFR conditions through this afternoon. A weak
cold front will make it`s closest approach from the west tonight
and early Fri before washing out altogether during Friday. MVFR
conditions possible this evening thru the overnight period. For
now will just indicate VCTS or VCSH during that time span.
Ceilings may lower to MVFR or even IFR if you choose the NAM
model. For now, will be more optimistic and indicate MVFR. Winds
will start out SSW 5 to 10 kt and increase to S 10 to 15 kt
with g20 kt this afternoon and evening. The higher gusts will
occur across the coastal terminals due to an active sea breeze.
Extended outlook...Isolated MVFR showers early FRI. Thereafter,
VFR through Sunday. Periods of IFR/MVFR in convection late
Monday into early Tuesday.
NEAR TERM /THROUGH THURSDAY/...
As of 330 AM Thursday...Light SW winds will be increasing in
speed today as a healthy cold front and upper wave approach from
the west. The upper system will be shunted to our north however
and the surface boundary will stall well west of the area. This
likely spares the region from needing an advisory though late
in the period there could be a few 25kt gusts as low level
jetting remains along the coast to promote mixing.
SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 330 AM Thursday...Sfc high pressure, ie. Bermuda high,
centered well offshore and ESE of the Carolinas, will be the
primary driver for winds and seas across the area waters. The
sfc ridge axis extending west from the high`s center will extend
westward and onshore in the vicinity of Cape Romain thruout this
period. This will result in Southerly winds across the local
waters, except SSW-SW from Cape Fear northward due to the
ridging placement. Windspeeds will run 10 to 15 kt with gusts to
20 to 25 kt possible especially the nearshore waters during the
evolution and any inland progression of the sea breeze.
Significant seas will run 2 to 4 ft thruout, except up to 5 ft
early Fri. Dominant direction will be from the SE early Friday
and more southerly late Fri thru Saturday night. Dominant
periods Fri will run 6 to 8 seconds then drop to 4 to 7 seconds
Fri night thru Sat night due to wind driven waves becoming the
LONG TERM /SUNDAY THROUGH MONDAY/...
As of 300 PM Wednesday...Bermuda High will maintain southwest
flow through much of the period. Speeds 10 to 15 kt Sun will
increase late Sun as gradient becomes more defined. Cold front
approaches from the west as the surface high shifts east. Speeds
increase to 15 to 20 kt Sun night and peak at 20 to 25 kt Mon
with low level jet approaching 40 kt. Seas around 3 ft Sat into
Sun will start building Sun night, approaching 8 ft on Mon.
Headlines may be required as early as Sun evening.