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Area forecast discussion 
National Weather Service Wilmington NC
630 am EDT Tuesday Jun 2 2015

Synopsis...
a cold front will make its way slowly toward the area today before
stalling nearby Wednesday...then becoming diffuse by the weekend.
There is a risk for showers and thunderstorms each day. The
thunderstorms will be most numerous through Thursday and some will
contain heavy rain. Another cold front will approach the area next
Monday.

&&

Near term /through tonight/...
as of 610 am Tuesday...no changes to the forecast with the latest
update. Previous discussion follows:

Long-anticipated change to the ongoing dry pattern in store
beginning today as deep moisture increases in advance of a slow-
moving cold front. Front will likely not actually make it into the
forecast area during the near term...however at the upper levels
an advancing h/5 trough with an embedded closed low and
accompanying cool air aloft will combine with a deeply moistened
column and daytime heating to substantially increase the
likelihood of convection today. Model soundings and radar loops
show probability of precipitation increasing from west to east today with best chances for
rain this afternoon and evening. Projected quantitative precipitation forecast values on the
modest side...ranging from a quarter inch near the coast to about
three- quarters of an inch inland through the near term...so as of
now not too keen on former heavy rain wording. Storm Prediction Center does have US in
a marginal risk area for severe storms today with the biggest
threat being from locally strong winds.

Substantial cloud cover and precipitation will help keep a lid on daytime
temperatures as compared to recent days...especially inland.
Forecast maximum temperatures today in the middle 80s most places and lower
80s at the coast. Overnight minimums in the middle to upper 60s.

&&

Short term /Wednesday through Thursday night/...
as of 330 am Tuesday...cutoff low over southern Appalachians/western
Carolinas will March slowly eastward and weaken a bit as it
reaches overhead by Friday morning. Plenty of moisture and energy
rotating around the low will enhance convection across the coastal
Carolinas through the period. This will combine with cold front
dropping down from the north in addition to convergence associated
with surface trough or reflection of upper low and along sea
breeze/land breeze and any other localized boundaries to produce
more widespread clouds and convective activity through middle week.
Steering flow remains very weak and therefore there will not be
much driving the showers/thunderstorms lending to potential for flooding.
May be tough to time exact periods of enhanced convection
associated with shortwave energy aloft which will also be followed
by some periods of increased subsidence lending to a decrease in
activity over spots. Overall expect unsettled weather with more
widespread shower/thunderstorm activity and possibly an isolated wet
microburst with damaging winds. Expect smaller diurnal ranges in
temperatures with plenty of moisture and clouds in place. Temperatures may not
even reach 80 during the day as 500 mb heights lower as cutoff moves
closer overhead. Overnight lows will be in the middle 60s to near 70.

&&

Long term /Friday through Monday/...
as of 300 am Tuesday...cutoff low should open up to trough as it
weakens slowly reaching overhead Friday morning. Looks like the best
energy associated with this upper level feature will shift off
shore by Friday afternoon as it begins to slip off the coast. At the same
time high pressure will build down behind from the north but looks
like lingering frontal boundary may hang around nearby as it
becomes more diffuse. A deeper northwest flow on the back end of the
upper low will provide a bit of drying and subsidence aloft heading
into the weekend...before flow flattens out. Expect residual low
level moisture and boundary to produce clouds and localized
showers/thunderstorms over the weekend...but the increased subsidence and
drier air aloft should keep convection more localized for the most
part with some brightening of skies. By Sun night into Monday
winds continue to veer around as high pressure shifts off the
northeast coast with a southerly return flow setting up by Monday
morning ahead of next cold front. Middle to upper trough will dig
down from the Great Lakes pushing this cold front east Monday into
Tuesday with increased shower/thunderstorm activity ahead and along front.
After a slightly less warm start to the long term...expect temperatures
to warm in increasing sunshine and rising heights as cut off low
departs by the weekend.

&&

Aviation /12z Tuesday through Saturday/...
as of 12z...an upper low centered to our west will send US a series
of short waves over the next 24 hours. This combined with high
precipitable water...old outflow boundaries...and the sea breeze
boundary will all contribute to multiple rounds of convection through
the forecast period. It will be difficult to time the
convection...but it is safe to say the showers and possible storms
will be most numerous in the afternoon and early evening...however
overnight convection is also expected. Mainly southerly flow is
forecast.

Extended outlook...a good chance for showers and thunderstorms
Wednesday through Saturday...mainly in the afternoon. Brief periods
of IFR conditions possible in the showers/thunderstorms.

&&

Marine...
near term /through tonight/...
as of 610 am Tuesday...no changes to the forecast with the latest
update. Previous discussion follows:

Light southerly winds of right around 10 kts will continue today
and tonight in advance of a very slow-moving cold front. Seas will
stay in their current 2 feet range through the period. We will
likely see more shower and thunderstorm activity over the
waters...especially this afternoon and evening.

Short term /Wednesday through Thursday night/...
as of 330 am Tuesday...a cold front will drop south as cutoff low
in the middle to upper levels over western Carolinas shifts east
reaching the Cape Fear waters by Friday morning. Overall gradient
remains weak allowing for more variable winds especially as
surface reflection to low and frontal boundary move slowly across.
Light southeast to S winds Wednesday morning will become more variable as front
drops south. Winds may reach up to 15 kts in southerly flow Wednesday
even and then become more variable to north-northwest by end of period. Seas
will be 3 feet or less most of the period...but except up to 4 feet
Wednesday night. However...locally higher seas will occur in and near
thunderstorms.

Long term /Friday through Saturday/...
as of 330 am Tuesday...cutoff low in the upper levels over the
coastal Carolinas Friday morning will lift off to the northeast
leaving a lingering front to become more diffuse through the
weekend. Overall expect light and variable winds Friday morning to
shift around becoming more northerly as front sags south. By
Saturday winds may come around to the southeast as sea breeze develops
and front weakens. Winds should shift around becoming more on
shore through Saturday as front remains nearby. Overall winds
should be light around ten knots or less. Seas will remain
basically 3 feet or less.

&&

Ilm watches/warnings/advisories...
SC...none.
NC...none.
Marine...none.

&&

$$

Synopsis...rgz
near term...rek
short term...rgz
long term...rgz
aviation...43
marine...rek/rgz

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