Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington NC
1019 am EDT Wednesday Apr 1 2015
a weak cold front will drop south of the area through this
morning...followed by dry high pressure today. This high will move
offshore Thursday leading to above normal temperatures through
late week. A cold front will cross early Saturday bringing a
chance for showers. Dry high pressure will settle back across the
area Sunday and into early next week.
Near term /through tonight/...
as of 1015 am Wednesday...cloud cover gradually clearing the are
for west to east this morning...with most places becoming sunny by
early afternoon. Our far inland and northern counties are already
in full sun. Forecast in good shape with no updates needed for the
latest update. Previous discussions follow:
Adjustments upward to sky cover was needed with the daybreak
update and a boost upward in dewpoints. No other revisions of note
as a dry front clears the area and high debris clouds sail
overhead through morning. The previous early morning discussion
Another pleasant and quiet Spring day aside from pollen storms
ejecting from local pines. Upstream thunderstorms over the
northern Gulf states and Tennessee Valley will send occasional cirrus
overhead of NE SC and southeast NC this morning. A dry cold front across
central NC will pass across the forecast area around daybreak.
Weak cool air advection and plentiful sunshine should bring
maximum temperatures to the upper 60s over interior southeast NC to the
low/middle 70s across inland NE SC. North-northeast wind flow this afternoon and
coolish near shore sea surface temperatures will cap beaches at
middle 60s. Clear and cool overnight with low settling deep in the
40s most localities...upper 40s beaches and very southern NE SC.
Short term /Thursday through Friday night/...
as of 300 am Wednesday...some very nice early-Spring weather for
the end of the week as high pressure offshore combines with
increasing middle-level ridging to produce warm temperatures with
ample sunshine. High pressure initially centered just off the NC
coast will push east through the period as a cold front approaches
slowly from the northwest. This front will be impeded in its longitudinal
gain thanks to increasing longwave ridging aloft...and thus most
of the impacts from this boundary will occur after the short term.
Before that occurs...warm advection on return flow along with the
raised thicknesses will produce temperatures above normal both Thursday
and Friday...with just a schc of showers until Friday night. Temperatures
Thursday will soar into the middle 70s...with widespread 80s expected
on Friday. Lows each night will also be quite warm around 60 both
nights...slightly warmer Friday night...as warm SW winds persist.
While Thursday will be dry with a lot of sunshine...shower
chances will gradually increase on Friday. Some typical Summer-
like air mass showers are possible during the afternoon...but the bulk
of the precipitation will hold off until after dark and towards daybreak
Saturday as the cold front approaches. Best forcing both at jet
level and within any positive vorticity advection remains well north of the area...and
guidance has backed off on total column saturation. Latest sref
plumes suggest very little quantitative precipitation forecast before the end of the period...and
will lower pop just slightly but maintain chance for Friday night.
The highest pop will be in the northwest zones. Thunderstorms appear
unlikely...and even shower activity looks to remain pretty light
through 8am Saturday.
Long term /Saturday through Tuesday/...
as of 300 am Wednesday...cold front will be on the doorstep
Saturday morning...and showers will likely be ongoing at daybreak.
Extended guidance is in pretty good agreement bringing the cold
front across the County Warning Area late morning...with rapid drying occurring by
Saturday evening. The European model (ecmwf) is a bit more robust with quantitative precipitation forecast Saturday
morning...but will lean on the lower quantitative precipitation forecast/lower pop guidance which
seems more reasonable based off lack of upper support and marginal
column saturation. Will walk pop back downward a bit Saturday
morning but maintain low-chance for the day. Thereafter...a return to
seasonable Carolina Spring weather will develop Sunday and
Monday...and potential into Tuesday as ridging re-develops aloft
and surface high pressure settles offshore. While Sunday will
likely be a bit below climatology...a warming trend begins Monday...with
above normal temperatures possible Tuesday. However...increased moisture
will lead to increasing afternoon shower potential late in the period.
Aviation /14z Wednesday through Sunday/...
as of 12z...frontal boundary has pushed through most of the County Warning Area
as evidenced by satellite. A lot of high clouds will be transiting
the region...courtesy of convective debris advecting in from the
west. Post frontal mainly northerly winds are expected today. High
pressure will remain overhead through the forecast period with
light winds tonight.
Extended outlook...slight chance showers Friday with a better
chance showers/MVFR Friday night into early Saturday. Otherwise
near term /through tonight/...
as of 1015 am Wednesday...no changes to the forecast with the
latest update. Previous discussion follows:
Cautionary headline expired at 6am. Winds shifting to north-north-northeast this
morning as a dry cold front moves north-northwest to south-southeast across the 0-20nm
waters. No thunderstorms or restrictions to visibility expected through
tonight. Seas mainly 2-4 feet highest offshore will settle to 2-3 feet
overnight with diminishing and weakening winds to east-northeast tonight.
Short term /Thursday through Friday night/...
as of 300 am Wednesday...high pressure just about overhead
Thursday morning will push offshore and continue to slowly drift
east through the end of the week. At the same time...a cold front
will approach from the northwest...and this will cause the pressure
gradient to pinch and winds to come around to the SW
Thursday...and then increase in speed quickly during Friday. Winds
early Thursday will be E/se...but quickly transition to SW and
then climb to 10-15 kts Thursday night...and then 20-25 kts Friday
night immediately ahead of the cold front. Wave heights will be
primarily driven by the increasing SW winds...rising from 2-4 feet
Thursday...to 4-7 feet Friday night...and a Small Craft Advisory is
likely beginning late Friday.
Long term /Saturday through Sunday/...
as of 300 am Wednesday...cold front will be just west of the
waters Saturday morning...and a Small Craft Advisory will likely
be ongoing to start the period due to 20-25 knots SW winds and seas
of 4-7 feet. This front will cross east of the waters Saturday
afternoon...turning winds quickly to the northwest and then NE with decreasing
speeds by Sunday morning. Wave heights will drop on the decreasing
winds and become 2- 4 feet by Sunday. High pressure behind this cold
front will build overhead the waters Sunday...which will drive a
very weak gradient which keeps winds light and variable...with
seas only 1-2 feet.