Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Mount Holly New Jersey
408 am EDT Friday Sep 19 2014
high pressure will slide across to the north of the region today and
then shifts offshore tonight. A cold front will cross the area
Sunday night into Monday. High pressure builds in from the west
Monday and persists through the end of the week.
Near term /until 6 PM this evening/...
winds are weak early this morning, but it appears the surface cold
front has made it across most, if not all, of our portion of the
As the day progresses, the surface high behind the front, now
centered over Quebec will slide south and push off the northeast
U.S. Coast. This shift will help produce and onshore flow and
begin to bring in Atlantic low level moisture.
Highs this afternoon will range from near 60 across the Poconos to
the middle 70s across Delaware-Maryland-Virginia.
North winds will become east by days end. Speeds will increase as
well this morning.
There is no precipitation mentioned for today. In general, a lower
confidence sky forecast. Current thinking is that there will be a
good amount sunshine before the onshore flow helps produce the
clouds. If there are more clouds than sun today, the models are
keying on the Poconos, Lehigh Valley, and northwest New Jersey.
Short term /6 PM this evening through 6 am Saturday/...
the period begins and ends with an onshore flow. Models, including
stat guidance, have clouds on the increase overnight. This looks
reasonable. In response to the deepening low level moisture, some
drizzle is possible across our upslope zones west of the Delaware
valley and locales along the coast.
Overnight lows will drop into the upper 40s across out northwest
zones and into the middle to upper 50s across the coastal plain.
Long term /Saturday through Thursday/...
Saturday...Saturday looks to be a pretty dry day across the region.
Although there will be a middle level shortwave rotating through, there
is not an abundance of moisture around and it doesn't look like we
will see much in the way of showers across the area.
Return flow around the departing high pressure will help to bring in
some moister and warmer air. Maximum temperatures will rise into the middle to
upper 70s across much of the region. Temperatures overnight will drop into
the upper 50s to lower 60s.
Sunday...a cold front will gradually push towards the region on
Sunday. However, the fronts progress appears to be on the slow side
and it likely wont reach the region until later in the day and won't
fully move offshore until late Sunday night/early Monday morning. We
have added a slight chance of thunder into the forecast for Sunday
afternoon/night. The instability isn't terribly strong but it is
available and we can't rule out a rumble or two across the region.
Best chances look to be out ahead of the front and chances will
diminish as we head into Sunday night.
Sunday will be the warmest day of the week across our area as maximum
temperatures reach into the 80s. Behind the front, temperatures will drop
and overnight lows will drop into the 50s. Where skies start to
clear a bit more, especially across the northwestern areas, we could
see temperatures drop down into the upper 40s.
Monday...the cold front pushes to the south of the area and we
should see some drier and cooler air moving in on the northwest
flow. Any lingering showers will clear quickly. Maximum temperatures will be
around 8-12 degrees cooler across the region. Most areas will see
maximum temperatures in the upper 60s to lower 70s. Overnight lows will feel
considerably colder, with most place dropping down into the 40s,
with some 50s possible closer to the coast.
Tuesday through Thursday...high pressure starts to build in from the
west on Tuesday. The high gradually shifts to the north of the
region and slowly moves across and into New England through the
week. This will keep the weather pretty dry with a south to
southeast flow across the region. A middle level shortwave will rotate
through the area on Tuesday and may spark off a few showers. For
now, we have kept the forecast dry as the soundings look pretty
Aviation /08z Friday through Tuesday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.
Today...VFR conditions. North winds to start the day, east winds to
finish. Should see the gradient tighten a bit and some winds in the
10 to 15 knots range.
Tonight...with the onshore flow, lowering and thickening clouds can
be expected. For now we'll drop things down to MVFR, 1500-2500 feet.
Some drizzle is possible, especially across kabe, krdg, kacy, and
kmiv. Winds will remain out of the east, but lighten up a bit.
Saturday through Saturday night...mainly VFR conditions expected.
Stratus/fog development possible Saturday night with lower ceilings
and visibilities into Sunday morning.
Sunday through Sunday night...fog/stratus possible early...then
mainly VFR conditions expected much of the day. Lower visibilities
and ceilings possible through the afternoon/evening in
showers/thunderstorms in advance of an approaching cold front. The
front will move through late Sunday into Monday.
Monday through Tuesday...mainly VFR conditions expected. Northwest
winds around 10 to 15 knots on Monday...less windy on Tuesday.
both buoy 44065 and 44025 are finally back!
Today...made some changes to today's northern water grids and added
Small Craft Advisory headlines. Could see some gusts end up in the 20 to 25 knots range.
This will help build 5 foot seas. Further south we'll hold off any
Small Craft Advisory headlines.
Tonight...also made some changes to the grids. We've backed off of
headlines and have delayed the Small Craft Advisory for the southern waters. Across
the northern waters, we'll have the Small Craft Advisory run through about 06z. Looks
like a lower end Small Craft Advisory with winds topping out around 20 knots and seas 5
Saturday...seas look to be elevated heading through
the day on Saturday and will gradually start to subside into
Saturday evening. The Small Craft Advisory has been extended
through late Saturday afternoon at this time. It may need to be
extended into Saturday evening for a period until seas fall below
5 feet. Winds look to remain below 25 knots across the waters.
Sunday...winds and waves are expected to remain below advisory
criteria through Sunday.
Sunday night through Monday...a cold front will cross the area
waters late Sunday into early Monday. Showers and thunderstorms will
accompany the frontal passage. In addition, winds and waves will
start to increase and a Small Craft Advisory may be needed.
Tuesday...sub-advisory conditions are expected as high pressure
moves into the region.
with long period swells still present today, a tightening gradient
and increasing wave heights, in house guidance continues to suggest
a moderate risk today for New Jersey and Delaware.
Marine...Small Craft Advisory from 2 am to 6 PM EDT Saturday for
Small Craft Advisory from 9 am this morning to 2 am EDT
Saturday for anz450-451.