Area Forecast Discussion
Issued by NWS Wilmington, NC-- Remove Highlighting --
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FXUS62 KILM 272316
Area Forecast Discussion
National Weather Service Wilmington NC
716 PM EDT SAT AUG 27 2016
Warm late summer conditions will prevail through the weekend. The
chance of showers will increase as well, as moisture from the
tropics moves across the area early next week. A strong cold
front is expected to move across the region late this week.
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
As of 630 PM Saturday...Latest 88D radar depicts a westward
moving of a cluster of thunderstorms across the NW portions of the
ILM CWA. Extrapolating this activity thru sunset, takes it out of
the ILM CWA by sunset. This will leave mainly popcorn type showers
and isolated thunderstorms which will decay especially with the
loss of the days insolation. During the remainder of the evening
and overnight, will see mostly clear skies near the coast and a
slow scouring of the convective debris clouds once the pcpn
activity ends. Very minor tweak to the overnight lows, with 70 to
75 degree readings inland, increasing to the 75 to 79 range for
the coastal counties.
As of 315 PM Saturday...Analysis of todays sounding data and latest
guidance shows convection will be limited today due to very dry air
and weak lapse rates aloft, a marginally unstable column and strong
upper ridging. Expecting only isolated to widely scattered showers
and thunderstorms into this evening as a result, mainly away from
the coast, with no severe weather likely. This activity will move
ahead of a slowly advancing and weak cold front which is the only
substantial trigger we will see today for convection.
For tonight, surface high pressure to the north will continue to
push the aforementioned cold front south towards the forecast area
as it further weakens and dissipates. There will be little to no
impact from this feature overnight, with no weather and only a
subtle wind shift to the NE assuming the front makes it this far
south. Guidance assumes that it will, with some post frontal stratus
in the early morning hours. Model consensus gives us minimum
temperatures in the mid 70s tonight.
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
As of 315 PM Saturday...The remnants of long-dead Fiona, now
manifesting itself as a loosely organized low with some tropical
features, is forecast to drift slowly west towards the local area
through the period as either a tropical-like wave or a weak low
pressure system. Due to the weakness of this feature, its slow
westward movement and poor prospects for development it is expected
that there will be little to no impact on the local area during the
short term. We will see a gradual return of deep moisture through
the period and improved chances for mainly diurnal convection.
Sunday looks to be the better day for rain chances as subsidence and
dry air to the west of the aforementioned system will help suppress
convection. Daytime temperatures will be seasonal or even a little
below depending upon extent of cloud cover. Nighttime temperatures
will remain a bit above normal with dewpoints remaining elevated in
the lower to mid 70s.
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 315 PM Saturday...Uncertainty is the theme for the extended
as several components namely tropical or possible tropical
entities are poised to affect the area. First, the moisture and
system moving across the Caribbean may shift to the north and west
and link up with yet another system, the remants of Fiona which
are forecast to move due east with possible redevelopment. A mid
level low churning off the southeast coast will be modulating the
moisture for the most part. Usually with systems similar to these,
the moisture remains mostly confined to the eastern half of the
system as continental air is just too much to overcome with weak
advection. Overall the strategy of chance to isolated pops for
Tuesday and Wednesday looks good with higher values along the
The end of the period is suddenly looking a bit messy as well. The
mid level trough that pushes a front through the area Friday and
Saturday looks somewhat weaker and mid level drying remains to the
north. I have incrementally increased pops and cloud cover to
Temperature forecast is at the mercy of the moisture and is low
confidence as well but didn`t make wholesale changes from the
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --As of 00Z...There is a chance of VCTS and MVFR from
reduced visibilities on convection northeast of KLBT that will move
across by02 utc. Also these scattered thunderstorms have a smaller
chance of moving across KFLO as heating of the day wanes. In any case
will include VCTS for both sites through at least 03 UTC.
With northeast flow expected in the lower levels tonight there is
a Chance for low level stratus before daybreak. Confidence is not
high as the low level flow weakens at all sites later tonight.
Have included a scattered deck of stratus generally after 09 utc.
Also will include MVFR for BR at KFLO and KILM.
After sunrise winds are expected to be from the northeast to east
at less than 10 knots with a broken deck of clouds at or above
EXTENDED OUTLOOK...Increasing chance of TEMPO sub VFR each day as
tropical moisture/shower potential increases through Tuesday. VFR
-- End Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
As of 645 PM Saturday...High pressure will re-establish its
ridging from the NE states tonight. This will result in east winds
around 5 kt becoming east to northeast around 10 kt toward
morning. Exception is nearshore thru the mid to late evening hrs,
where the sea breeze has produced a fading e to se wind at 10 to
15 kt. Have backed down on the pcpn coverage to isolated and that
will mainly occur during the pre- dawn Sunday hours. Significant
seas will run 2 to 4 ft which have mainly been a function of a 2
to 4 foot swell at 9 second periods mainly from the remnants of
Fiona. This will continue thru the overnight with wind-driven
waves having little input, other then a small chop on top of the
As of 315 PM Saturday...High pressure to the north will push down
a weak and dissipating front south towards the waters overnight.
There will be little to no impact from this feature, with no
weather and a negligible wind shift. We can expect gradually
increasing long-period swell from distant tropical systems, but
seas will overall remain in their present 3 to 4 ft range. East
winds will maintain at around 10 kts or so through the period.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 315 PM Saturday...The remnants of long-dead Fiona,
now manifesting itself as a loosely organized low with some
tropical features, is forecast to drift slowly west towards the
waters through the period as either a tropical-like wave or a weak
low pressure system. Due to the weakness of this feature, its slow
westward movement and poor prospects for development it is
expected that there will be little impact upon the local waters.
Expect NE to E winds in the 10 to 15 kt range through the short
term. Seas will stay mainly in the 3 or 4 ft range, although some
5 footers over our outer waters are possible due to the
contribution of swell energy from distant yet slowly strengthening
LONG TERM /TUESDAY THROUGH THURSDAY/...
As of 315 PM Saturday...With all that may be going on the winds
will be somewhat benign. For Tuesday and into early Wednesday
winds will be mostly from the northeast and ten knots or less. A
weak pattern later Wednesday will be followed by a possible
frontal passage Thursday with a shift to northwest winds. Not much
in the way of CAA with the front so speeds remain ten knots or
less. Significant seas will be 2-4 feet but longer period swell
may continue to warrant some rip current hazards.