Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Mount Holly New Jersey
415 PM EST Sat Nov 28 2015
a cold front will move southward through our region tonight. High
pressure will build into the area from eastern Canada and New
England on Sunday night and Monday. Low pressure develops east of
the Carolinas Monday night and move northward off the New Jersey
coast on Tuesday. A cold front will move through our region on
Wednesday. High pressure builds in from the west late in the week.
Near term /until 6 am Sunday morning/...
the cold front has sagged across the central part of the area
early this afternoon, and will continue to slowly sag southward
into this evening, eventually pushing south of the area overnight.
Light rain continues to fall along and behind the boundary. As
additional short wave/vorticity impulses approach and move into
the area overnight, the rainfall is forecast to increase in
coverage and become more widespread. It looks like the area with
the best chance for the more steady rainfall overnight will be the
southern half of New Jersey, southeast Pennsylvania, as well as
the Delaware-Maryland-Virginia. The rainfall continues to be expected to be mostly
light, with total amounts of a tenth to a quarter of an inch. The
northern half of the area will have rainfall through this evening,
but once the rain moves out of this area, it should remain rain
free the rest of the night.
Short term /6 am Sunday morning through 6 PM Sunday/...
there should be rainfall ongoing across the southern portions of
the area during the morning hours Sunday, before pushing to our
south as the moisture/lift associated with the short
wave/vorticity impulses pushes south of the area. Rainfall should
continue to be on the light side, with around a tenth of an inch
of rain across the southern areas during the morning before the
rainfall tapers off.
High pressure begins to build out of southern Canada into New
England Sunday night, with our area on the southern periphery.
This should help keep everyone dry, with the exception of extreme
southern Delaware-Maryland-Virginia where some lingering showers may affect the
area. Any showers will be light though.
Long term /Sunday night through Saturday/...
the main focus for this portion of the forecast will be a storm
system impacting the region during the Tuesday-Wednesday period.
Some showers may linger on Monday in Delaware-Maryland-Virginia associated with a
stalled frontal boundary to our south. Attention then turns to a
storm system moving through the Great Lakes region, which leads to a
overrunning regime Monday night into Tuesday, as the front to our
south returns northward as a warm front. As mentioned previously,
there is the potential for at least some freezing drizzle Monday
night into Tuesday morning. Both Tuesday and Wednesday will be the
warmest days of the week, with temperatures several degrees above normal.
There could be some heavy downpours during the day on Wednesday,
prior to a cold frontal passage Wednesday night.
Otherwise, generally fair weather is expected from Thursday through
Saturday, with temperatures near normal.
Aviation /21z Saturday through Thursday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.
MVFR ceilings are starting to make their way southward into the area
this afternoon as Abe/rdg/ttn have lowered so far. These lowering
ceilings will continue to move southward, and should affect all sites
by this evening. IFR conditions are also possible during the
overnight into Sunday morning, but we've only included this for
Acy/miv who have the greatest potential. The lower ceilings are
expected to continue into Sunday morning, and begin to lift and
potentially clear out from north to south as drier air moves in
from the north.
Westerly winds ahead of the front will become northwest as the
front moves through the area. Later this evening and overnight,
winds will become north north to northeast and continue through
Sunday. Speeds will generally be 5-10 knots or less.
Monday...generally VFR except MVFR possible at both Acy and miv.
Monday night through Tuesday night...MVFR and possibly IFR in low
clouds and periods of rain.
Wednesday...MVFR conditions should gradually improve to VFR from
southwest to northeast.
Wednesday night through Thursday...generally VFR conditions
anticipated at this time.
we decided to keep the Small Craft Advisory going for hazardous
seas as buoy 44091 remains bouncing around 5 feet. Buoy 44009 and
44065 are below 5 feet, so it won't be long before 44091 falls
below as well. So we'll keep the ending time of 6 PM for now. Once
the seas fall below 5 feet, they should remain below 5 feet
through Sunday. A cold front will sag south of the waters tonight
and will remain to our south Sunday, while high pressure builds to
our north Sunday night. Seas and winds may again approach or reach
Small Craft Advisory levels late Sunday night.
Monday through Tuesday...low pressure moving through the coastal waters
will likely necessitate the need for a Small Craft Advisory /sca/
for seas during this time frame.
Wednesday and Thursday...a cold frontal passage on Wednesday will
lead to westerly winds, with the best chance of those winds
meeting the Small Craft Advisory criteria on Thursday.
the WSR-88D located at Fort Dix New Jersey will be down at least until
Monday, November 30. The parts needed to repair the radar are on
Marine...Small Craft Advisory for hazardous seas until 6 PM EST this
evening for anz450>455.