Area Forecast Discussion
Issued by NWS Wilmington, NC-- Remove Highlighting --
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FXUS62 KILM 280311
Area Forecast Discussion
National Weather Service Wilmington NC
1111 PM EDT Tue Sep 27 2016
A cold front approaching from the west will stall through mid-
week before moving across the area Thursday into Friday. Dry high
pressure will build into the area by the weekend.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 11 PM Tuesday...Forecast area is now convection free
and although latest guidance shows small chances for renewed
activity do not feel comfortable completely ruling it out for the
overnight period given storms passing to the north and west of
us. NC counties will see the best chances for renewed convection
after midnight, although confidence not especially high. Relevant
portion of previous discussion from this afternoon follows:
Expect areal extent of convection to diminish during the evening.
Have trended POPs a little lower along the coast, while have
increased them a notch across the Pee Dee and Lumberton areas. A
blend of MAV/MET numbers looks reasonable for overnight low
temperatures in the upper 60s inland to the lower 70s at the
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
As of 300 PM Tuesday...A large upper low will continue to evolve
across the Midwest and Ohio valley Wednesday through Thursday as
it slowly meanders toward the south-southeast. This feature will
gradually push a cold front across the area late Thursday. Given
how amplified the pattern is aloft would not be surprised if the
frontal passage is delayed a little further. Thus the forecast
area will remain in the warmer sector through most of the short
term period and the chance for showers and thunderstorms will
persist as well. An impulse is shown to wrap around the upper low,
likely passing to our northwest during Thursday. SPC continues to
highlight central NC with a Marginal Risk of severe tstms. Part of
this risk area includes as portion of the Lumberton area and
northern parts of the Pee Dee. The highest precipitable water
values remain off the coast through Thursday with much lower values
beginning to filter in from the west Thursday night. As mentioned
earlier, the timing is suspect given the orientation of the front
to the flow aloft. A blend of MAV/MET numbers appears reasonable
each day and night.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 300 PM Tuesday...Deep large cutoff low over the Ohio
Valley on Friday will lift slowly north toward the Great Lakes
over the weekend before heading east and weakening over the
northeast states. At the same time, a broad ridge will persists
across the Atlantic reaching westward toward the southeast coast.
The upper low will drive a front east, and it should be aligned
along or just off the southeast coast on Fri. Although the sfc
winds should shift around to the west and become light and
variable, the deep S-SW flow aloft will keep front stalled with a
deep southerly flow above. The moisture profiles and sounding date
show plenty of dry air wrapping around the potent mid to upper low
keeping it very dry in the mid levels Friday into the weekend.
The lingering boundary should remain near or just east of the
area, but the deep moisture, clouds and convection should stay
east and off shore until later in the weekend, at which time the
upper low will lift far enough off to the north. This may draw
some of the moisture back toward the coast for early next week,
but tough to say if it will make it back into forecast area before
getting pushed away as high pressure builds down from the north.
The next big variable is a tropical system which models show
heading north from the Caribbean, possibly reaching as far west as
Cuba before making the turn north. This may come into play in the
forecast heading into end of the forecast period or the middle of
The dry air wrapping around the upper low should produce drier
weather for the weekend, but the location of the actual sfc
boundary will determine if relatively cooler, lower dewpoint air
makes it in for Fri or the weekend. For now, will show lower
dewpoint air advecting in from the west on Friday and possibly
remaining through at least Saturday with overnight lows dropping
down toward 60 and even below 60 inland Fri night and possible Sat
night. Afternoon highs should still be up around 80 in plenty of
late September sunshine through much of the period.
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
As of 00Z...Potential for MVFR/IFR overnight due to fog development,
along with any heavy downpours on Wednesday. Otherwise expect VFR
with VCSH/VCTS through the period.
Latest radar imagery depicts light showers moving across portions of
the forecast area, which may affect KLBT/KILM over the next few
hours. Otherwise, fairly quiet conditions are expected for the rest
of tonight with light winds. Late overnight into the early morning
hours, latest guidance and trends continue to suggest fog
development across the area, which may create periods of MVFR/IFR.
After daybreak, VFR will prevail with isolated to scattered showers
and thunderstorms. South-southeast winds 5 to 10 kts expected on
EXTENDED OUTLOOK...Scattered SHRA/TSRA through Thursday. A cold
frontal passage late Wednesday into Thursday. Primarily VFR
expected Friday through Sunday.
NEAR TERM /THROUGH TONIGHT/...
As of 11 PM Tuesday...latest obs continue to show very light NE
winds over the waters with seas around 3 ft and no convection.
This is in accordance with the present forecast. No changes
planned with the latest update. Previous discussion from this
Weak area of low pressure will quickly move by the adjacent
waters later this afternoon and evening before departing to the
northeast. The resulting wind field will be variable at 10 knots
or less. Seas will be 3 ft or less tonight.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 300 PM Tuesday...The flow will eventually become
southeasterly during Wednesday in response to a slow moving cold
front approaching from the west. Additional veering to the
southwest with an increase in speed is expected by Thursday
evening just ahead of the cold front. Seas will be 3 ft or less
Wednesday through Thursday morning, then possibly 3-4 ft by
LONG TERM/FRIDAY THROUGH SUNDAY/...
As of 300 PM Tuesday...A cold front will make its way east
through the Carolinas and into the local waters on Friday, causing
winds to shift from SW at 5-10 kts early, to NW at 5-10 kts late.
The sfc pressure pattern will remain weak into the weekend as mid
to upper low dominates the weather. As the upper low lifts north
by the end of the weekend, the boundary should be drawn back west
shifting winds back around. Overall, the winds may become quite
variable, remaining light through the weekend. Seas will be 2 to 3
ft through the weekend with a longer period, up to 13 second, SE
swell mixing in Sat night into early Sun from a developing
tropical system well out in the Atlantic waters.