Area Forecast Discussion
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FXUS62 KILM 270530
Area Forecast Discussion
National Weather Service Wilmington NC
130 AM EDT Tue Sep 27 2016
A front will lift north tonight while a cold front approaches
from the west. This second boundary will stall to our west
until moving again later in the week and pushing through
late Thursday. Drier air will then build in over the weekend.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 1030 PM Monday...It looks like the the warm front has passed
just to the north of the forecast area. Some light showers are
approaching the coast as a coastal trough forms. This is as
forecast. Previous discussion follows:
The stationary front that was located just to the south of the
forecast area is slowly moving northward as the observations at
Kingstree and Georgetown are now reporting a more northeast and
east flow with increased dewpoint seen at Kingstree.
The water vapor imagery also is indicting the mid and upper moisture
has begun it shift northward. Scattered convection has developed
along a boundary from Longs, SC to Kingstree. So will continue with
a slight chance of POPs from SC this evening.
The models continue to show the development of a coastal trough with
a low pressure area forming and moving up the coast just offshore on
late tonight. So with this low pressure area will increase
precipitation chances to ~30-40% along the coast and a 20% chance
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
As of 3 PM Monday...The short term forecast period will be marked
with a cold front sliding into the forecast area and then
stalling. This front will be a focal point for showers and
isolated thunderstorms each day.
On the synoptic scale a large upper-level low just north of Lake
Superior will shift to Ohio Valley by Wednesday night. This feature
will be bringing a significant air mass change but this does not
begin until after the short term forecast period.
The slow moving cold front will be the focus for the heaviest rain
on Wednesday into Wedensday night with QPF values running between
just over 1". Maximum Temperatures on Tuesday and Wednesday are
expected to rise to the middle 80s with the warmer temperatures west
of Interstate 95. For lower temperatures values will range from the
upper 60s inland to the lower 70s at the coast.
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 3 PM Monday...Cold front to come through on Thursday
according to the slightly preferred GFS though some proverbial
points to be made regarding how early or late in the day or at
night. Still worth noting that the EC is still much slower with
FROPA not until Friday night-a solution that WPC is still not able
to rule out. Even with the large and stalled low pinwheeling over
the OH valley over the weekend we will remain well in the dry slot
by Friday (unless EC is correct) which should bring quiet weather.
We may not get into the much cooler air however as it appeared
recently and the later part of the period may simply bring
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
As of 06Z...Slow moving cold front well NW of the terminals, and a
developing weak low pressure along the coast, will maintain ample
cloudiness and possible showers through the valid period. A few
showers have developed along the coast so far this morning, and this
is likely to continue through daybreak. Do not expect coverage to be
widespread enough for a VCSH mention, so have added a TEMPO group at
ILM/CRE/MYR for periodic and brief MVFR. The inland terminals will
likely remain dry as the showers along the cold front to the NW are
forecast to dissipate as they drop SE. While cloud cover will be
significant, much of it will remain the mid-levels, so light fog is
possible overnight at LBT/FLO, with winds just above the surface
likely too strong for any IFR vsby restrictions.
Scattered showers will again be possible during Tuesday aftn/eve,
but coverage is expected to be light enough that no mention of any
restrictions has been added attm. Best chance for showers during the
day will be along the coast, but will handle this potential with
later updates. Winds will be generally from the east and less than
10 kts beneath VFR cigs. More stratus will again be possible Tuesday
night, especially along the coast.
EXTENDED OUTLOOK...Scattered SHRA/TSRA Tuesday through Thursday.
Cold frontal passage Thursday. VFR expected fRI/SAT.
NEAR TERM /THROUGH TONIGHT/...
As of 1030PM Monday...Latest obs continue to show easterly winds
of 10 to 15 kts with seas of right around 3 ft. This fits in well
with the going forecast. No changes made with latest update.
Previous discussion follows:
A stationary front is located near the Georgetown coastal waters
and is expected to shift northward overnight. To the south a
coastal trough will develop with a low pressure area moving to the
southern coastal waters by daybreak.
Winds will mainly be from the east overnight at 10 to 15 knots with
seas ranging between 2 to 4 feet. A 1 to 2 foot easterly swell is
also expected to continue through the period.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 3 PM Monday...As a coastal low shifts northward along the
coast, a slow moving cold front will stall before shifting off the
coast late wednesday night. winds are expected to shift to the
southwest tuesday night but winds speeds are expected to be 10-15
knots. seas will continue to run between 2 and 4 feet. Showers and
thunderstorms are possible throughout most of this period.
LONG TERM/THURSDAY THROUGH SATURDAY/...
As of 3 PM Monday...Cold front coming through on Thursday though
how early or late highly uncertain. There are in fact some
currently not favored but still possible model solutions that are
24 hours or more slower. Best forecast possible at this time is to
show a later day veer from W to NW with no appreciable change in
the very light wind speeds. The cutoff nature of the upper low
driving this front precludes any surge of high pressure into the
area and so the post frontal flow regime stays light as well. NW
winds should be in place both Fri and Sat with seas no higher than
2 to 3 ft.