Area Forecast Discussion
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FXUS62 KILM 252043
Area Forecast Discussion
National Weather Service Wilmington NC
343 PM EST Sat Feb 25 2017
Near record high temperatures today will fall abruptly behind a
cold front this evening. Much cooler temperatures expected
Sunday as high pressure builds into the Carolinas. These cool
temperatures will be short lived as a warm front lifts north
early Tuesday. Near record high temperatures expected again the
middle of next week before a cold front crosses the area on
Thursday. A return to winter like temperatures is possible by
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
As of 300 PM Saturday...Thee see-saw battle with sea fog looks like
it has finally ended. Flow in the lower levels has become more SW-
WSW and has also increased. Latest sat imagery shows cloudiness now
moving off the mainland coasts of the Carolinas. This flow will also
push drier air off the coast as evidenced with coastal obs along
Horry and Georgetown coasts indicating sfc dewpoints having dropped
into the 50s. Fortunately, this should end any visibility issues due
to onshore movement of sea fog with the sea breeze having been over-
ridden by the strong SW- WSW flow in the lower levels. Some tweaking
downward of aftn highs along coastal counties due to the earlier sea
breeze lasting longer than expected and keeping temps pinned from
rising. May see a degree or 3 recovery with highs reaching possible
record highs before all said and done.
Clouds ahead and associated with the eastward moving cold front will
pushing across the area this aftn thru atleast early evening. Only
limited moisture avbl for low level cu/sc and mid level altocu by
the time the cold front makes it to the ILM CWA. Latest model
trends indicate this limited moisture to scour out even more-so as
it progresses east. Latest HRRR indicates this dry scenario for the
ILM CWA with the cold front pushing across the FA and offshore by
mid-evening. By daybreak Sun, models indicate 1000-500mb thicknesses
dropping into the mid 540s and 850mb temps to 0 to +2 degrees C. CAA
will be in full later this evening and overnight under active NW
winds, gusty for several hours immediately after the CFP itself.
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
As of 300 PM Saturday...The flow aloft will de-amplify this period
with nearly zonal flow aloft. At the sfc, Sunday will see the
effects from Cool Canadian high pressure affecting the area with
temps basically at or slightly below the norm thru Sun night. With
fast flow aloft, the center of this sfc high is progged to push
across the coastal areas Sunday night and to well offshore and east
of NC during Monday. Return flow around the departing high will
result in WAA under SE to S flow during Monday with max temps
rebounding back to around 70 away from the immediate coast. There is
a weak mid-level s/w trof that passes just north of the FA during
Mon night. Enough moisture accompany`s this s/w as well a SE influx
of limited moisture at the low levels off the Atlantic. Have
indicated POPs increasing to low chance Mon evening and modest
chance later Mon night. QPF will be on the light side, under one
quarter of an inch.
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 300 PM Saturday...A warm front will be lifting north of the
area Tuesday morning, with very warm conditions expected through mid-
week. Temperatures Tuesday will be well into the 70s, and by
Wednesday with strong WAA and better coverage of sunshine, record
highs may be approached (low 80s for March 1st). While it will
likely be very warm both Tue/Wed, an early-spring unstable
environment will likely permit aftn showers and isolated tstms
across the area, more widespread on Tuesday than Wednesday. A strong
cold front will then cross the Carolinas Thursday with a good chance
for showers and tstms during the morning into the early aftn, before
much cooler and drier weather advects into the region. Thursday will
likely again be warm, with potentially an atypical diurnal curve
through the aftn behind the FROPA, before a trough digs down the
eastern seaboard behind the front. After several days well above
normal, it appears winter will make a return for the first wknd in
March with highs and lows below climo Fri and Sat.
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
As of 18Z...Southwest flow will remain gusty as winds veer to a more
westerly direction as cold front approaches from the west. A small
area of sea fog crept into the Myrtles as the winds backed to a more
southerly direction. This will only last for an hour or so and will
move out of terminals as winds shift back to a more SW direction.
The cold front will cross the terminals without any restrictions to
TAFs. Winds will pick up out of the west just ahead of the front
late this afternoon, with fropa expected this evening. Moderate
northwest flow tonight will become northerly and lighten by 08-
10z in strong CAA.
Extended Outlook...VFR. VSBY and ceilings lowered to MVFR/IFR
with pcp Mon night into Tues and again with SHWRs on Wed.
NEAR TERM /THROUGH TONIGHT/...
As of 315 PM Saturday...Well the sea fog issues have finally abated.
Given latest sat imagery and local obs, the low level flow has
become more of a SW-WSW direction, eliminating whats left of the sea
breeze. With lower sfc dewpoints having begun to push off the
mainland this aftn, the threat for sea fog will also diminish given
this influx of drier air.
The sfc pg has tightened ahead of the approaching cold front and
will yield increasing SW to WSW winds ahead of the cold front.
Speeds will reach SCA values across the ILM NC waters, and SCEC
thresholds for the ILM SC Waters. Winds will veer to the NW after
the CFP around mid evening and persist thru the remainder of the
night. The CAA surge will combine with the tightened gradient to
produce continued SCEC thresholds for the SC Waters with 15 to 20 kt
and gusts up to 25 kt. For the NC Waters, winds will increase to 20
to 25 kt and hold thru the majority of the night. Significant seas
will run a healthy 3 to 5 ft SC Waters and 3 to 6 ft NC Waters. The
ESE 11 second period ground swell has peaked earlier today, however
it will remain a dominant force remainder of today and may equal out
with locally produced wind driven waves with regard to it`s power
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 315 PM Saturday...Sfc high pressure centered just west of the
spine of the Appalachians at Sunday Daybreak. A tightened sfc pg and
diminishing CAA will keep winds frisky for the 1st half of Sunday.
Progressive flow aloft and translating this to the sfc will result
in the high`s center moving to the Eastern Carolinas early by Sun
evening and to well offshore and east of the NC mainland by daybreak
Mon. Winds will diminish to around 10 kt late Sun thru Sun night.
Return E to SE flow on the back-side of the departing high will
increase across the local waters during Monday...further veering to
the S and SW and slightly increasing to around 15 kt Mon night.
Significant seas will drop to 1 to 3 ft by Sun night into Mon
followed by a building trend Mon night, remaining just below any
Advisory or Cautionary thresholds.
LONG TERM /TUESDAY THROUGH THURSDAY/...
As of 300 PM Saturday...Gusty SW winds ahead of a cold front
will plague the waters Tue and Wed, with 10-15 kt winds Tuesday
rising to 15-20 kts on Wednesday. FROPA is expected early
Thursday accompanied by showers and a wind shift to the W/NW
with continued speeds of 15-20 kts through late Thursday.
Highest seas will occur late Wednesday into Thursday just ahead
of the cold front, with 4-7 ft waves are expected and an SCA may
be required. Otherwise, seas will be 2-4 ft during Tuesday on
the light winds, and then Thursday thanks to the offshore
MARINE...Small Craft Advisory until 6 AM EST Sunday for AMZ250-252.