Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington NC
653 am EST sun Mar 1 2015
light rain will spread across the area today as moisture overruns
a cool surface airmass. A cold front will move through on Monday
and set up a cool Tuesday. Wednesday will warm up into the 70s on
Wednesday ahead of another cold front that will bring unsettled
weather Thursday into Friday. Cool weather will last into the
Near term /through tonight/...
as of 3 am Sunday...isentropic lift over cooler air near the surface
continues at this time and is forecast to continue through much of the day
into tonight. This should result in periods of rain into tonight.
There remains the threat that it will begin as or transition to
freezing rain northwest through middle morning before changing to all
rain. Maximum temperatures will range from around 40 northwest to around 50
along the coast. Rain will end from west to east tonight with lows
in the upper 30s to lower 40s.
Short term /Monday through Tuesday night/...
as of 3 am Sunday...monday's highs may end up close to climatology just
ahead of a cold front. Moisture associated with this boundary will
be largely confined to the lower levels. So while cloudy conditions
prevail rainfall chances will be little. That may change Monday
night as moisture aloft begins to overrun the surface wedge brought
about by the frontal passage. Generally any rain will be light and likely
confined to southern zones. These rainfall changes should ooze
northward on Tuesday as the warm air advection strengthens over the
boundary layer. Should rain continue to re-enforce The Wedge then a
cool day is on tap and statistical output is fairly supportive of
such. But raw model output shows The Wedge breaking down and it
seems that temperature deviations from climatology may be a bit smaller than
previously forecast especially over southern zones.
Long term /Wednesday through Saturday/...
as of 3 am Sunday...Wednesday still looks to be the warmest the area
has experienced in some time as many locations save for beaches warm
into the low 70s despite ample cloud cover. Rain chances appear low
and confined to northwestern zones with the approach of a cold front that
comes through Wednesday night. Rain chances linger into Thursday as
the baroclinicity lagging behind the surface boundary pushes south
and east across the area. Temperatures take a big hit with highs
possibly once again mired in the 40s. Did not go quite as cold as
MOS guidance as that would be too large a change and prone to flip
flopping between various guidance runs. Weak confluent flow aloft
keeps high pressure building into the area over the weekend while
some moisture may slosh back atop the boundary layer according to
the ec. GFS more in line with previous forecast in keeping moisture
farther south and bringing some sun locally over the weekend. Either
solution favors temperatures well below climatology...the GFS would imply larger
deviations at night than the cloudier solutions.
Aviation /12z Sunday through Thursday/...
as of 12z...MVFR ceilings are occurring at the inland terminals this
morning. At kilm ceilings are borderline IFR while kcre/kmyr have VFR
ceilings. Just intermittent light rain has occurred.
Strongest lift...albeit mostly in the low/middle levels...is forecast to
begin around middle morning. Expect MVFR conditions to continue and
spread to the kcre/kmyr terminals. Kilm may encounter the best
flight conditions today with IFR not expected to develop until late
this afternoon. Overall though there will be an increasing
likelihood of IFR as lift increases this morning and persists into
the afternoon. Rain should increase today but taper off from SW-NE
this afternoon into early this evening.
Extended outlook...IFR becoming VFR Monday. Periods of MVFR/showers
late Tuesday into Thursday. Otherwise VFR.
near term /through tonight/...
as of 6 am Sunday...small craft remains in effect northern waters
through 10 am this morning for seas of 4 to 6 feet. Otherwise expect
3 to 5 footers today to subside to 2 to 4 feet by tonight. NE winds
of 15 to 20 knots today are expected to become S to southeast at 10 to 15 knots
this afternoon...then shift to the west tonight.
Short term /Monday through Tuesday night/...
as of 3 am Sunday...cold frontal passage brings offshore/nwrly winds
that will remain moderately light early on. As the day wears on high
pressure building into the middle Atlantic region will veer the flow to
more northeasterly and add a few knots of wind speed and perhaps a
foot to offshore dominant wave height. Even so no flags or headlines
anticipated. By Tuesday the parent high will have progressed a bit
eastward offshore while a weakening ridge axis is maintained into
the Carolinas. Coastal front developing will turn the flow more
onshore possibly grabbing some advisory-worthy 6 feet seas and
dragging them into the very outer reaches of some of the forecast
Long term /Wednesday through Thursday/...
as of 3 am Sunday...the approach of a fairly strong cold front will
bring a tightened low level jet on Wednesday. The airmass ahead of
this boundary will be quite warm and it remains to be seen how much
of this wind will mix to the surface as cooler SSTs inhibit vertical
mixing over the shelf waters. Have been carrying 6 feet seas but
starting to think this may be a tad overdone and advisory level
conditions a little hard-pressed to materialize. Given it being far
out in time however did not make any real changes. Behind the
boundary on Thursday though some cooler air should pour into the
region. This seems like a better time frame for winds and/or seas to
satisfy Small Craft Advisory conditions.
SC...Freezing Rain Advisory until 11 am EST this morning for scz017-
NC...Freezing Rain Advisory until 11 am EST this morning for ncz087-
Marine...Small Craft Advisory until 10 am EST this morning for amz250-