Scientific Forecaster Discussion
fxus62 kilm 241035
Area forecast discussion
National Weather Service Wilmington NC
635 am EDT Sat Jun 24 2017
remnant tropical moisture from previous storm Cindy will pass
across the region this afternoon through early Sunday, bringing
a good chance of rain, which may be heavy at times overnight.
Slightly cooler and much drier air will move into the region
early next week. A warming trend is expected mid to late of
Near term /through tonight/...
as of 3 am Saturday...water vapor imagery shows a plume of
moisture across the Tennessee Valley poised to move east today
as broad troughing sets up across the eastern U.S. A cold front
will move across the Carolinas slowly through tonight
associated with the trough. This along with the Piedmont trough
when combined with precipitable water values of well over two
inches points to widespread convection this afternoon extending
into the overnight hours. We have maintained likely to
categorical pops for this time. Localized flooding will likely
be the primary threat although there is some shear present and a
wet microburst or two is possible. Temperature forecast is
straightforward with highs around 90 and overnight lows in the
Short term /Sunday through Sunday night/...
as of 3 am Saturday...by daybreak Sunday the axis of maximum
precipitable water values will be edging offshore, taking the potential for
the heaviest of rainfall with it to sea. Surface convergence
however will linger farther inland intrinsic with the surface
trough, and thus rain should be ongoing at this time, in a
scattered to likely fashion, favored across the eastern zones
where the overlap with higher column moisture prevails. Through
the day on Sunday showers should be tapering off from west to
east primarily due to 800 mb-h6 drying. The surface trough/front
will cross the coast Sunday afternoon so maximum temperatures
Monday may be a few degrees cooler compared to Sunday even
though the air may be slightly rain-cooled Sunday. Relatively
cooler air to usher in Tuesday, middle and upper 60s and drier.
Moisture will linger along and near the coast Monday where
isolated convection may form, but could just end up as cumulus.
Long term /Monday through Friday/...
as of 300 PM Friday...mid level troughiness sharpens through
Tuesday. Initially a dry westerly flow but a slightly more
moisture-laden west-southwest flow through Tuesday. Daytime temperatures
will be held a bit below climatology through this time frame.
The trough axis appears to swing through on Wednesday bringing a
more decided drying. The rest of period will be characterized
by a building upper ridge over the southeast and Bahamas. This
will mark a transition back towards seasonable temperatures and
isolated convection mainly during the diurnal maximum.
Aviation /12z Saturday through Wednesday/...
as of 1035z...isolated MVFR cigs this morning, then expect
mostly VFR conditions, until later today as showers and
thunderstorms become increasingly widespread, as deep moisture
returns to the area along with the Piedmont trough with a cold
front late in the period. Certainly some MVFR and even IFR is
possible in and near +shra and thunderstorms. Moisture tropical in
nature may restrict visibilities below 1/4sm in torrential rain late
this afternoon and overnight. Showers to decrease in coverage
and intensity from west to east after 12z Sunday.
Extended outlook...MVFR/IFR conditions are possible in
thunderstorms Saturday night and into Sunday. Thunderstorms are
expected to be most numerous Saturday evening and overnight.
near term /through tonight/...
as of 3 am Saturday...quite gusty across all areas this morning
and the coastal waters are no exception. The winds oddly enough
are from a belt of strong 850mb winds that can be traced back
to Tropical Storm Cindy. The stronger winds will essentially
remain over the waters while subsiding inland. Expect a roving
range of 20-25 knots to at times 15-20 knots through tonight.
Seas will be 4-6 feet with a Small Craft Advisory continuing.
Short term /Sunday through Monday night/...
as of 3 am Saturday...this will be an improving marine period as
both winds and seas drop off, as a front nears and moves off the
coast. SW wind-waves will dampen through the day Sunday, but an
opposing northwest-north later Sunday will cause a bit of sea state
confusion but conditions will still improve because the Post
frontal winds will not be all that strong. Monday however a
slight high pressure surge could bring 20 knots gusts so seas may
hold in a 2-4 foot range. Sunday morning visibilities offshore
may range from 1-3 nm in areas of heavy showers and storms.
Long term /Tuesday through Wednesday/...
as of 300 PM Friday...not a typical summertime pattern in place
for most of the period. A sharpening mid level trough will be
in place. A series of weak surface boundaries may come through
but with only very minor fluctuations of wind direction, though
a northerly component will dominate. Wind speeds never really
look to exceed 10kt by much though a few higher gusts will be
possible. Seas will average 2 to occasionally 3 ft with near
shore wave shadowing much more pronounced than usual this time
of year where SW winds much more common.
SC...beach hazards statement through this evening for scz054-056.
NC...beach hazards statement through this evening for ncz106-108.
Marine...Small Craft Advisory until 6 am EDT Sunday for amz250-252-254-