National Weather Service United States Department of Commerce

 


163
FXUS62 KILM 261918
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
317 PM EDT Mon Jun 26 2017

.SYNOPSIS...
An upper disturbance will bring a few showers late on Tuesday
followed by a reinforcement of cooler and drier air through mid
week. Summer warmth and humidity will return late week into next
weekend with isolated to scattered thunderstorms.

.NEAR TERM /THROUGH TUESDAY/...
As of 300 PM Monday... Just a few stratus/stratocumulus clouds
trapped underneath the frontal inversion for the remainder of the
day. They have proved enough to keep temperatures just a bit below
climatology. Guidance has shown that this moisture will erode for
all but coastal areas early tonight. Then later tonight into
tomorrow morning the offshore boundary will weaken if not wash out
entirely. This may allow for some very shallow moisture to creep
back onshore but not to where fog seems likely to form. Later
Tuesday a cold front driven by a healthy upper trough and vort max
will approach from the northwest. The upper system appears likely to
be the main rain-maker Tuesday since deep moisture recovery will not
have time to occur. This may mean that NC deserves some slightly
higher POPs than SC but for now prefer a broad-brush 30 area-wide
since measurable rainfall may not happen at all.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 3 PM Monday...Any lingering showers and thunderstorms will be
ending as the a shortwave exits to the northeast Tue night. The
shortwave drags a secondary cold front across the area early Wed
with a cooler and much drier air mass building in for the middle of
the week. Precipitable water values drop under 0.75 inches Wed and a
mid level subsidence inversion develops as the 5h trough exits and
weak 5h ridge starts to build. High pressure northwest of the area
early Wed shifts east, passing north of the area Wed evening. The
high ends up off the coast as the period ends with weak return flow
just starting to develop. Subsidence and the abundance of dry air
will ensure the period is dry once any lingering activity Tue
evening comes to an end. Temperatures will run below climo through
the period with lows in the low to mid 60s and highs in the mid 80s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 3 PM Monday...Long term period will be marked by the return of
weather more typical of late June as Bermuda high pressure ridges
back into the area. High temperatures will increase from the mid to
upper 80s Thursday to the upper 80s to lower 90s for the remainder
of the period. Lows will increase from upper 60s to lower 70s
thursday night to the low to mid 70s for the remainder of the
period. Thursday should be the last dry day with isolated to
scattered showers and thunderstorms, mainly in the afternoon and
evening, during the rest of the period.

&&

.AVIATION /18Z MONDAY THROUGH FRIDAY/...
As of 18Z...Generally MVFR most locales with widespread
stratus/stratocumulus present due to a front stalled across the area.
Medium confidence regarding precipitation associated with this
boundary. Showers and storms should generally move up the GA/SC
coast into SC/NC coast this evening but in weakening states that
will be hard pressed to further lower flight category for long. The
front moves offshore overnight. Moisture may hang tough at the coast
overnight while inland areas see a drying trend.

Extended Outlook...Flight restrictions possible with isolated
showers and thunderstorms early Monday and again Tuesday during the
afternoon hours.

&&

.MARINE...
NEAR TERM /THROUGH TUESDAY/...
As of 300 PM Monday...With a frontal boundary offshore weakening if
not completely washing out overnight winds will show considerable
variability and speeds will remain minimal. Seas also quite minimal
with no appreciable swell energy to speak of. Just as a light
onshore flow seemingly starts getting established early Tuesday
afternoon another cold front pushes through turning winds to N or NE.


SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 3 PM Monday...Northerly flow will develop early in the period
as high pressure to the northwest builds in following the passage of
cold front. Gradient behind the front is not particularly tight and
speeds will remain under 15 kt Tue night. Surface high is quick to
move east Wed and Wed night. Northeast flow Tue night into Wed
shifts to easterly Wed evening and eventually southeast by the end
of the period. Speeds Wed and Wed night will be 10 kt or less. Seas
will be around 2 ft through the period.

LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 300 PM Monday...SE winds around 10 kt will become S to SW by
Thursday night and continue through Saturday though speeds could top
out around 15 kt by Saturday. Seas around 2 feet are expected most
of the period with a few 3 footers possible Saturday.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.

&&

NEAR TERM...MBB
SHORT TERM...III
LONG TERM...XXXI
AVIATION...MBB