Area Forecast Discussion
Issued by NWS Mt. Holly, NJ
Issued by NWS Mt. Holly, NJ
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FXUS61 KPHI 151148
AFDPHI
Area Forecast Discussion
National Weather Service Mount Holly NJ
648 AM EST Sun Feb 15 2026
.WHAT HAS CHANGED...
Decreasing likelihood of dense fog early this morning, though some
patchy fog remains possible.
Snowfall forecast remains largely unchanged, with the highest totals
near and north of the I-195 and PA Turnpike corridors.
Confidence is increasing in above normal temperatures for the
upcoming week, breaking a prolonged cold spell.
&&
.KEY MESSAGES...
1. Fog development remains possible early this morning leading to
pockets of reduced visibility. As temperatures are below
freezing, with many locations falling into the 20s, freezing
fog is a concern.
2. Low pressure moves through the Mid-Atlantic Sunday night through
Monday, bringing rain and snow to the area.
3. Above normal temperatures return to the area by the middle of
next week.
4...An unsettled pattern takes hold for the upcoming week, with
multiple chances for rain, and potentially some mixed precipitation
in northern areas.
&&
.DISCUSSION...
KEY MESSAGE 1...Fog development remains possible early this morning leading to
pockets of reduced visibility. As temperatures are below
freezing, with many locations falling into the 20s, freezing
fog is a concern.
An area of high pressure is overhead early this morning, resulting
in light and variable to calm winds. There will be warmer air moving
northward aloft while at the surface we remain colder, especially
helped by the snowpack still on the ground. This will result in a
prominent inversion which is shown in model soundings. Low-level
moisture looks to get trapped below this inversion. One key part of
this is that our dew points are higher than previous days. All of
this is leading to the potential for patchy fog development.
Another concern with the fog is this being freezing fog as
temperatures this morning are below freezing and in the 20s for
most. Freezing fog can result in a light glazing of ice on
untreated surfaces, particularly elevated surfaces.
KEY MESSAGE 2...Low pressure moves through the Mid-Atlantic Sunday
night through Monday, bringing rain and snow to the area.
Low pressure currently over the southern Mississippi River Valley
will track east along the Gulf Coast states through the day today. A
warm front will develop out ahead of this low, and on this warm
front, overrunning precipitation west of the area will lift into
Delmarva, extreme southern New Jersey, and the Delaware Valley late
this afternoon. Temperatures will be warm enough for precipitation
to be plain rain.
Going into tonight, low pressure tracks into the Southeast, then
lifts north into the Mid-Atlantic area. 00Z model guidance has
largely stayed in line with the low coming off of Cape Hatteras late
Sunday night, then tracking out to sea on Monday.
QPF amounts largely remain the same as a result, as have snowfall
amounts. Given that surface temperatures will generally be in the
low to mid 30s across northern New Jersey and the Lehigh Valley, can
expect snow ratios there to be on the order of 10:1. Farther south,
ratios will be lower, as surface temperatures will be in the mid 30s
or so, and just above freezing. The highest QPF will be across the
southern half of the forecast area, where precipitation will be
mostly rain, on the order of 1/2 to 3/4 inch, with locally as high
as 1 inch. Where it will be snow, QPF should be on the order of
around 1/4 inch.
Most guidance has come into two camps, either showing a narrow
corridor of higher snowfall totals, mainly in the 1-2 inch range,
with less than 1 inch elsewhere or light snowfall totals less than 1
inch everywhere. The 00Z GFS remains a notable outlier from both of
these camps, with a much wider swath of 2-3 inches of snow. As a
result, the likelihood of needing an advisory for any locations has
decreased significantly, though can`t quite be ruled out completely.
Primarily stuck with NBM for Snow Ratios, along with WPC QPF, ending
up with similar totals of 1 to 2 inches of snow for most of New
Jersey north of I-195 and the Lehigh Valley, and less than an inch
elsewhere.
KEY MESSAGE 3...Above normal temperatures are expected for most of
the upcoming week
High pressure builds into the Eastern Seaboard on Monday, then
establishes itself offshore Tuesday through Wednesday. Return flow
sets up at the surface and zonal flow sets up aloft. This allows for
warm air advection to develop, and temperatures will finally push to
above normal levels.
We start the week with temperatures near normal in the low to mid
40s, but temperatures get into the mid to upper 40s and low 50s
from Tuesday through Friday. Highs Thursday and Friday may even
touch 60 over Delmarva.
In terms of overnight lows, Monday Night will feature temperatures
in the upper 20s and low 30s, with this being the last night below
freezing for some locations. Tuesday Night through Friday Night will
feature lows in the 30s, with areas south of I-78 likely staying
above freezing.
After over two weeks now of snow on the ground, warmer temperatures
will finally allow the snowpack to melt more quickly. However,
mostly cloudy skies due to the unsettled pattern for this week will
limit the snowmelt a bit.
KEY MESSAGE 4...An unsettled pattern takes hold for the upcoming
week, with multiple chances for rain, and potentially some mixed
precipitation in northern areas.
Several waves of low pressure will move through the area this week,
bringing some much needed rain (and potentially some mixed
precipitation up north).
The first system to move through will be the weakest and most areas
will stay dry. A weak shortwave dives in from the northwest on
Monday, potentially bringing some light precipitation to the
southern Poconos and northern New Jersey. Added an area of 20% PoPs
on Monday Night and the precipitation type remains a bit uncertain.
The favorable timing (late Monday Night/early Tuesday morning) could
result in some light freezing rain/drizzle or snow, especially in
the higher elevations. It bears watching but expecting any
precipitation to be light and relatively unimpactful.
The next system, and potentially more impactful comes Wednesday
afternoon into Wednesday Night. Latest run of the NBM has a mainly
rain event, but some of the 00z guidance again hints at mixed
precipitation or even snow in the far reaches of our area - along
and north of I-80. Stuck with the NBM for now, but certainly cannot
rule out some freezing rain or snow, especially if the system comes
in later and timing is more favorable. However, there is rather high
confidence in this system being mainly rain for most of the area
outside of far northern NJ and the southern Poconos. QPF amounts
should be rather light - NBM Probability of 1 inch or more of QPF is
less than 10% for the entire area. However, our area could certainly
use some rain and this could be the first measurable rain for some
in almost a month or more (given how cold it has been,
precipitation type has been all snow).
Almost rinse and repeat for the end of the week as an area of low
pressure likely slides by to the north. Again, this should mainly be
an all rain event for most, if not all of the region given the track
of the low. However, similar to the mid-week system, if more
precipitation comes during the overnight hours, higher elevation
areas in the southern Poconos and far northern NJ could see some
snow or freezing rain. NBM Probability of QPF over 1 inch is a bit
higher than the mid-week system, but still only around 20-30%. The
details will be ironed out over the next couple days, especially
once the timing comes more into focus.
Overall, a slew of systems will bring primarily rain to most of the
area, with the potential for mixed precipitation in far northern New
Jersey and the southern Poconos. With these systems though, we are
not currently expecting moderate or major impacts. In fact, for most
of the region, it will be more of a beneficial rain.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas...
Today...Mainly VFR conditions after any lingering MVFR
conditions due to fog dissipate. Between 22z-00z, ceilings
lower to MVFR as rain/snow arrives from south to north. East
winds 5-10 kt. Low confidence.
Tonight through Monday...MVFR or IFR in RA or SN. Best chances for
SN will be at KRDG/KABE/KTTN, RA and SN at KPNE/KPHL/KILG, and RA at
KMIV/KACY. Conditions gradually improve on Monday as precipitation
departs. Northeast winds around 5-10 kts. Low confidence.
Outlook...
Monday Night...Primarily VFR, though some MVFR conditions possible
(50%).
Tuesday through Tuesday Night...VFR. No significant weather.
Wednesday through Wednesday Night...Sub-VFR conditions expected with
rain showers and low ceilings moving through.
Thursday...Primarily VFR, though some lingering MVFR/IFR conditions
possible (30-40%).
&&
.MARINE...
Sub-SCA conditions expected through today. West-southwest winds
around 10 kts or less this morning, gradually shifting to be
out of the east by midday. Seas 1 to 2 feet. SCA conditions
possible by late Sunday night for wind gusts over 25 kt, with
the passage of a front but the window for these elevated wind
gusts will be short. VSBY restrictions in rain or snow Sunday
night into Monday morning.
By Monday morning, seas are expected to build to be in excess of 5
feet for coastal Atlantic waters. A Small Craft Advisory is in
effect beginning at 6 AM Monday. Sub-SCA conditions are expected
along the Delaware Bay.
Regarding the river/bay ice...Ice cover continues across many area
bay waters and inland estuaries. This includes, but is not limited
to the Delaware estuary. On rivers, the ice thickness is enough to
cause some restrictions in the flow. Per satellite imagery and ice
analysis data, the Delaware River is mostly ice covered from the
Delaware Memorial Bridge upstream, to at least Washington Crossing,
though we are seeing improvement with warmer temperatures that will
only get better with warmer days ahead.
According to latest analysis from the National Ice Center, Delaware
Bay is actually mainly ice-free with less than 10% coverage of ice.
The most common ways river ice can break up is either through a
thermal or mechanical means. We would like to see temperatures rise
into the 40s for a few days, which parts of the region are forecast
to get to once again this weekend with some areas getting into the
50s early next week. Significant rainfall, producing river rises,
can also break up ice but that is not in the forecast this week.
As a result, ice cover will gradually decline over the next week or
so and we are already seeing major improvement in Delaware Bay.
Outlook...
Monday Night through Tuesday...A Small Craft Advisory is in effect
for all ocean zones. Seas of 4 to 6 feet expected. Winds will be
relatively light out of the north and west - around 10 kt or less.
Sub-SCA conditions expected on Delaware Bay.
Tuesday Night...Lingering 5 foot seas could result in an extension
to the Small Craft Advisory on the ocean.
Wednesday through Thursday...No marine headlines expected.
&&
.EQUIPMENT...
KDIX will remain out of service through at least Sunday,
February 15.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory from 6 AM Monday to 6 PM EST Tuesday for
ANZ450>455.
&&
$$
DISCUSSION...AKL/Hoeflich
AVIATION...AKL/Hoeflich
MARINE...AKL/Hoeflich