Area Forecast Discussion
Issued by NWS Wilmington, NC-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS62 KILM 221749
Area Forecast Discussion
National Weather Service Wilmington NC
149 PM EDT SUN MAY 22 2016
-- Changed Discussion --Low pressure and an associated cold front will move farther
offshore. An area of low pressure aloft will bring a slight
chance of showers this afternoon and again on Monday. Typical
Summertime temperatures and mainly dry weather will develop by the
middle of the week with above normal temperatures into next
-- End Changed Discussion --
.NEAR TERM /THROUGH TONIGHT/...
As of 1215 PM Sunday...The CU/SC field has transitioned nicely
across the fa once insolation was able to make it to the sfc. Have
expanded this cu field across much of the ILM SC CWA given latest
vis sat imagery trends. Will also expand the POP field across the
remaining Temps aloft will slowly drop ahead of the upper low
dropping southward. Model consensus places the cold core upper
lows furthest southern extent across eastern NC by daybreak Mon.
500 mb temps by morning will have dropped from -14 degrees C early
this aftn to -20 degrees C by daybreak Mon.
A s/w mid-level trof rotating around the upper low is progged to
push across portions of the FA late in the pre- dawn Mon hours and
continuing thru daylight Mon mid- morning. Models have been
consistent with this along with avbl moisture. The question is
will there be enough instability to mention thunder during the
pre-dawn Mon hrs. For now, have kept thunder out until daylight
Mon where just enough insolation becomes avbl. With more
cloudiness and threat of pcpn tonight than previously fcst, will
tweak min temps upwards by a degree or 2.
As of 845 AM Sunday...Post frontal very light rain or drizzle
accompanied by patchy fog will occur this morning as a
stratus/stratus fractus post frontal cloud deck persists thru the
mid to possibly late morning hrs. This pcpn activity will occur
mainly across the ILM NC CWA. From midday thru early evening...the
cloudiness across the area will transition to a cu/sc field with
breaks in the cloudiness, especially across the ILM SC CWA. Temps
thru the morning hrs have been adjusted lower, mainly across the
ILM NC CWA to account for this cloud deck and spotty pcpn. Temp
trends will resume to the previous fcst after the noon hour.
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 300 AM Sunday...Cold mid-level temperatures associated with
upper level low pressure near Virginia Beach Monday should spark
more scattered showers Monday afternoon. Coverage should be a bit
less than on Sunday due to drier low-level conditions yielding
less instability. Temperatures should remain well below normal
with highs only reaching the lower 70s for coastal SE North
Carolina, mid 70s from Lumberton to Myrtle Beach, and maybe some
upper 70s from Darlington to Florence. (Normal highs are in the
lower to middle 80s this time of year!) Surface high pressure
building eastward from the Plains states will reach the Carolinas
Monday night providing light winds and mainly clear skies.
Radiational cooling should drop lows into the mid 50s for most
locations away from the beaches.
On Tuesday light winds and plenty of sunshine coupled with warm
advection as the upper low and surface high both move offshore
should allow temperatures to soar into the 80s away from the
beaches. Mainly clear skies will continue Tuesday night with lower
to mid 60s.
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 300 AM Sunday...Middle to later half of the week will be
marked by surface high moving off the coast and weak ridging
aloft. Surface high just off the coast Wed migrates to the a more
typical Bermuda High location Thu through Sat. As the high
offshore drifts east a 5h ridge will build over region, leading to
warming and drying conditions during the period. Latest GFS and
ECMWF depicting a much stronger 5h ridge than just 24 hours ago.
The mid level ridge remains a "dirty ridge" with moisture aloft
emerging from the southwest and topping the ridge. While chances
will be very low this will at least mean isolated afternoon
convection will be possible late in the week. Will carry silent
afternoon/evening pop Thu through Sat but confidence is low.
temperatures will run above climo through the period.
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --As of 18Z...IFR stratus has broken up leaving mainly MVFR/VFR
conditions for this afternoon. A cold front will continue to
drift farther off shore as a mid to upper low and associated cold
pool aloft move into and across area tonight into Monday. This
cold pool will produce some convection through this afternoon
across the TAF sites but will dissipate into this evening. Light
winds with mainly scattered skies will follow for tonight.
Included a bit of MVFR fog for coastal terminals.
Extended Outlook...Possible MVFR conditions on Monday, otherwise
-- End Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
As of 1215 PM Sunday...Cyclonic flow around the upper low dropping
south will result in nNW to N winds at 10 to occasionally 15 kt
thruout this fcst period. significant seas will hold around 3 ft
for the waters from Cape Fear northward...and 2 to 3 ft south of
the Cape to South Santee River. A decent 1 to 2 foot ese ground
swell at 8 to 9 second periods will primarily dominate today into
tonight. The offshore nnw-n wind chop will become more evident
the further away from the immediate coast 1 progresses. This wind
chop will be limited in growth due to the offshore nature of the
wind and resulting small fetch to grow.
Showers and isolated storms may move off the mainland later this
aftn and evening. A mid-level s/w trof will begin to push across
the waters toward daybreak Mon, resulting with another bout of
pcpn moving off the mainland during this time frame.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 300 AM Sunday...Low pressure will develop Monday morning
along this morning`s cold front which should be located a couple
hundred miles offshore. The low will move northward and away from
the area, but will help to keep northerly winds blowing around 10
knots with some 15 kt winds possible Monday morning north of Cape
Fear. Scattered afternoon showers may again develop Monday due to
the cold and unstable conditions aloft.
For Monday night through Tuesday night the focus will shift to high
pressure building in from the west. This high should bring
delightful weather with light winds and no appreciable rain
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
As of 300 AM Sunday...Surface high centered just east of the
waters Wed morning will drift farther east Wed night, setting up
in the typical Bermuda High location Thu. Southwest flow is
expected across the waters through Thu night with speeds on the
low end of the 10 to 15 kt range. Sea breeze is likely to develop
each afternoon, resulting in onshore flow close to 15 kt near the
coast. Seas 2 ft or less Wed and Thu.