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Area forecast discussion 
National Weather Service Mount Holly New Jersey
424 am EST Tuesday Mar 3 2015

Synopsis...
high pressure will move farther out to sea through today. As low
pressure moves through southeast Canada tonight, a warm front will
lift through the area overnight, followed by a cold front during the
day Wednesday. The front will push to our south into Thursday while
low pressure develops and moves along the boundary. High pressure
will return to the middle Atlantic region for Friday and Friday night.
A frontal passage is expected Saturday into Saturday night, followed
by high pressure again Sunday into Sunday night. Another frontal
passage is expected Monday into Monday night.

&&

Near term /until 6 PM this evening/...
high pressure was located over our region at 400 am. Temperatures
were mainly in the teens up north and in the 20s elsewhere. High
clouds were approaching from the west.

The high will slide off the coast today. Clouds will lower and
thicken and precipitation will arrive from the west this afternoon.

Based on the forecast temperature profiles, the precipitation should
begin as snow but transition quickly to sleet in our southern and
central counties. We could see a change to rain shortly after the
onset in our far southern counties. Temperatures should rise into
the middle 20s in the north, around 30 in our central counties and
into the middle 30s in the south by evening.

The presence of sleet should keep the snow/sleet accumulations
somewhat limited. We may see an inch or two of snow/sleet in our far
north through this evening, with around an inch possible from Berks
County, Pennsylvania eastward into central New Jersey. Less than an
inch of snow/sleet is anticipated for locations to the south.

&&

Short term /6 PM this evening through 6 am Wednesday/...
strong warm advection aloft will continue into this evening. We will
lose any potential for snow or ice pellet development and our event
should transition quickly to one of freezing rain and rain. Warming
at the surface will work its way gradually northward tonight.
However, locations in the Poconos and in far northern New Jersey may
not quite get to the 32 degree mark by daybreak on Wednesday.

We have made a few minor adjustments to the Winter Weather Advisory,
most notably the addition of Monmouth County, inland Ocean County
and southeastern Burlington County. The advisory remains in place
mainly over concerns for accumulating ice. It appears as though the
southern part of the advisory area could see a few hundredths of an
inch, while up to around a tenth of an inch of ice is possible in
the northern part of the advisory area.

Much of the coastal plain is forecast to rise into the 40s tonight
with a southeast to southwest wind. Readings are expected to be
mainly in the 30s in areas to the northwest of the Interstate 95
corridor.

The guidance has been trending downward with rainfall amounts. We
are expecting anywhere from a quarter to three quarters of an inch
which should not cause much of a problem even with some snow melt.

&&

Long term /Wednesday through Monday/...
the start of the long term forecast begins with a messy forecast,
but improving weather does return by the end of the week and
weekend.

A cold front will be making its way across the area during the day
Wednesday as precipitation should be on going. Temperatures will
be rising as a warm front will have lifted north of the area, and
everyone is expected to change over to rain. There could be some
lingering freezing rain across far northeast Pennsylvania and
northwest New Jersey, so we extended the advisory a couple of
hours. As the front continues through the area and sags just to
our south, we may get a break in precipitation late in the day as
the lead short wave moves past our area. However, this will only
be temporary.

The next short wave aloft is expected during the evening and
overnight, while an area of low pressure develops along the
frontal boundary to the south. This should push another area of
precipitation across the area during the evening and into the
overnight. With the front to our south, temperatures are expected
to cool through the night. While precipitation may begin as rain,
it is expected to transition to a wintry mix, before changing over
to all snow. The GFS and European model (ecmwf) are closer to one another with
their thermal profile and show this transition better than the
NAM. The NAM has a large warm nose well above the surface and
would lead to more sleet. While we think there will be a couple of
hours of sleet when the transition begins, the forecast is more
in line with the GFS/ECMWF.

The low pressure moving along the front will push offshore to our
south early on Thursday and move to our east through the day.
Meanwhile, the main trough aloft will be approaching during the
day and help kick the whole system away from the area by the end
of the day. However, before this all moves out, the snow will have
to progress through the remainder of the area.

All in all, it looks like our entire area will see an
accumulating snowfall, with the I-95/I-295 corridor possibly
seeing the most snow with as much as 6-8 inches possible, with
less on either side. This would have a large impact on the
morning rush Thursday.

All precipitation should be ending by the evening Thursday.
Clearing conditions will return to the area, along with another
shot of cold air. Overnight lows are expected to once again return
to single digits for much of the area overnight Thursday into
Friday morning.

High pressure briefly returns to the area Friday into Friday
night. This will continue the cold weather. Temperatures will
remain well below normal, although Friday night is not expected
to be as cold as Thursday night.

A frontal boundary is expected Saturday into Saturday night,
although there is not much moisture associated with it at this
time. So for now the forecast will remain dry.

High pressure once again briefly returns to the area Sunday into
Sunday night, before another frontal boundary approaches Monday
into Monday night. Again not much moisture is expected with this
frontal boundary either, so for now we will keep the weather dry
through Monday.

&&

Aviation /09z Tuesday through Saturday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

The following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

VFR conditions are expected through around 1900z to 2000z, then
conditions will deteriorate rapidly as snow and sleet build into our
region from the west.

We are anticipating mainly IFR conditions for this evening and
tonight. The snow and sleet should transition through freezing rain
then to rain for tonight.

A light and variable wind this morning is expected to settle into
the southeast and south for this afternoon and evening around 5 to
10 knots. The wind may shift toward the southwest late tonight.

A low level southwesterly jet is expected to develop over our region
tonight. As a result, we have included low level wind shear.

Outlook...
Wednesday...MVFR/IFR conditions with periods of rain expected.

Wednesday night-Thursday...rain early, changing to a wintry mix then snow overnight and continuing into Thursday. Accumulating snowfall is expected for the taf sites overnight Wednesday into Thursday.

Thursday night...improving to VFR during the evening.

Friday-Saturday...mostly VFR.

&&

Marine...
high pressure will pass of the coast and move out to sea today. A
north to northwest wind around 10 knots this morning should become
southerly for this afternoon. The wind is expected to be south to
southwest for tonight. Wind gusts may begin to approach 25 knots
tonight and waves could build near 5 feet on our ocean waters. It
appears to be a marginal situation. However, a Small Craft Advisory
may be needed eventually.

Outlook...
Wednesday-Wednesday night...sub-Small Craft Advisory conditions
expected, although winds may gust near 20 knots. A frontal
boundary is expected later Wednesday into Wednesday night.

Thursday-Thursday night...Small Craft Advisory conditions
expected to develop behind the cold front and continue into
Thursday night.

Friday-Saturday...sub-Small Craft Advisory conditions return.

&&

Phi watches/warnings/advisories...
PA...Winter Weather Advisory from 3 PM this afternoon to 6 am EST
Wednesday for paz060>062-105.
Winter Weather Advisory from 3 PM this afternoon to 1 am EST
Wednesday for paz070-071-101>104-106.
Winter Weather Advisory from 3 PM this afternoon to 9 am EST
Wednesday for paz054-055.
New Jersey...Winter Weather Advisory from 3 PM this afternoon to 6 am EST
Wednesday for njz007>010.
Winter Weather Advisory from 3 PM this afternoon to 1 am EST
Wednesday for njz012>020-027.
Winter Weather Advisory from 3 PM this afternoon to 9 am EST
Wednesday for njz001.
Delaware...Winter Weather Advisory from 3 PM this afternoon to 1 am EST
Wednesday for dez001.
Maryland...Winter Weather Advisory from 3 PM this afternoon to 1 am EST
Wednesday for mdz008-012.
Marine...none.

&&

$$

Synopsis...Robertson
near term...iovino
short term...iovino
long term...Robertson
aviation...iovino/Robertson
marine...iovino/Robertson

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