Alert archive / Pennsylvania / Winter Weather Advisories in 2020

Winter Weather Advisory 4, NWS Philadelphia/Mount Holly

February 4, 20206 counties in Pennsylvania; 5 counties in New Jersey

NWS Philadelphia/Mount Holly issued this winter weather advisory at Feb 4, 2020, 2:54 PM EST for 6 counties in Pennsylvania; 5 counties in New Jersey. It took effect at Feb 5, 2020, 8:00 PM EST. It was in force for 14 hr.

The area

The counties it named.

The facts

Issued
Feb 4, 2020, 2:54 PM EST (19:54 UTC)
In effect from
Feb 5, 2020, 8:00 PM EST
Expired
Feb 6, 2020, 10:00 AM EST
In force
14 hr
Issued by
NWS Philadelphia/Mount Holly

Counties Hunterdon County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 108 km from the middle of the area, began a volume at 19:56 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.9 hours before the alert went out and 194 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2020-02-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2020-02-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 155 square meters per square second.1939587897117136Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1384 m above ground
0-6 km bulk shear
83 kt
0-1 km storm-relative helicity
155 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

822 
WWUS41 KPHI 041954
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
254 PM EST Tue Feb 4 2020

NJZ001-007-008-PAZ054-055-062-051100-
/O.NEW.KPHI.WW.Y.0004.200206T0300Z-200206T1500Z/
Sussex-Warren-Morris-Carbon-Monroe-Northampton-
Including the cities of Newton, Washington, Morristown, 
Jim Thorpe, Stroudsburg, Bethlehem, and Easton
254 PM EST Tue Feb 4 2020

...WINTER WEATHER ADVISORY IN EFFECT FROM 10 PM WEDNESDAY TO
10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations up to a
  quarter inch.

* WHERE...In Carbon, Monroe, and Northampton Counties in 
  Pennsylvania, and Sussex, Warren, and Morris Counties in New 
  Jersey.

* WHEN...From 10 PM Wednesday to 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The
  hazardous conditions could impact the morning commute. Scattered
  power outages are possible due to the accumulating ice.

* ADDITIONAL DETAILS...Freezing rain amount will likely be higher
  in elevations above 1000 feet however small amounts remain
  possible down to valley floors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

NJZ009-010-PAZ061-105-051100-
/O.NEW.KPHI.WW.Y.0004.200206T0300Z-200206T1500Z/
Hunterdon-Somerset-Lehigh-Upper Bucks-
Including the cities of Flemington, Somerville, Allentown, 
Chalfont, and Perkasie
254 PM EST Tue Feb 4 2020

...WINTER WEATHER ADVISORY IN EFFECT FROM 10 PM WEDNESDAY TO
10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of up to
  one to two tenths of an inch.

* WHERE...In New Jersey, Hunterdon and Somerset. In 
  Pennsylvania, Lehigh and Upper Bucks.

* WHEN...From 10 PM Wednesday to 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The
  hazardous conditions could impact the morning commute. A few
  isolated power outages are possible as well.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
Deal
7 follow-up statements
365 
WWUS41 KPHI 050836
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
336 AM EST Wed Feb 5 2020


PAZ060-052100-
/O.EXB.KPHI.WW.Y.0004.200206T0100Z-200206T1500Z/
Berks-
Including the city of Reading
336 AM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of 
  around one tenth of an inch.

* WHERE...Berks.

* WHEN...From 8 PM this evening to 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The 
  hazardous conditions could impact the morning commute.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along
  and north of the Interstate 78 corridor. South of the Interstate
  78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

NJZ001-007-008-PAZ054-055-062-052100-
/O.EXT.KPHI.WW.Y.0004.200206T0100Z-200206T1500Z/
Sussex-Warren-Morris-Carbon-Monroe-Northampton-
Including the cities of Newton, Washington, Morristown, 
Jim Thorpe, Stroudsburg, Bethlehem, and Easton
336 AM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY NOW IN EFFECT FROM 8 PM THIS EVENING
TO 10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of one 
  tenth to two tenths of an inch.

* WHERE...Portions of northern New Jersey and east central and 
  northeast Pennsylvania.

* WHEN...From 8 PM this evening to 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The 
  hazardous conditions could impact the morning commute.

* ADDITIONAL DETAILS...Freezing rain amounts will likely be 
  higher in elevations above 1000 feet however small amounts 
  remain possible down to valley floors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

NJZ009-010-PAZ061-105-052100-
/O.EXT.KPHI.WW.Y.0004.200206T0100Z-200206T1500Z/
Hunterdon-Somerset-Lehigh-Upper Bucks-
Including the cities of Flemington, Somerville, Allentown, 
Chalfont, and Perkasie
336 AM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY NOW IN EFFECT FROM 8 PM THIS EVENING
TO 10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of 
  around one tenth of an inch.

* WHERE...In New Jersey, Hunterdon and Somerset. In 
  Pennsylvania, Lehigh and Upper Bucks.

* WHEN...From 8 PM this evening to 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The 
  hazardous conditions could impact the morning commute.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along
  and north of the Interstate 78 corridor. South of the Interstate
  78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

Johnson
504 
WWUS41 KPHI 052004
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
304 PM EST Wed Feb 5 2020


NJZ001-007-008-PAZ054-055-062-061000-
/O.CON.KPHI.WW.Y.0004.200206T0100Z-200206T1500Z/
Sussex-Warren-Morris-Carbon-Monroe-Northampton-
Including the cities of Newton, Washington, Morristown, 
Jim Thorpe, Stroudsburg, Bethlehem, and Easton
304 PM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of one
  tenth to two tenths of an inch. Locally higher amounts up to
  three tenths of an inch possible.

* WHERE...Portions of northern New Jersey and east central and 
  northeast Pennsylvania.

* WHEN...From 8 PM this evening to 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The
  hazardous conditions could impact the morning commute. Isolated
  to scattered power outages will be possible.

* ADDITIONAL DETAILS...Freezing rain amounts will likely be 
  higher in elevations above 1000 feet however small amounts 
  remain possible down to valley floors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

NJZ009-010-PAZ061-105-061000-
/O.CON.KPHI.WW.Y.0004.200206T0100Z-200206T1500Z/
Hunterdon-Somerset-Lehigh-Upper Bucks-
Including the cities of Flemington, Somerville, Allentown, 
Chalfont, and Perkasie
304 PM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of 
  around one tenth of an inch.

* WHERE...In New Jersey, Hunterdon and Somerset. In 
  Pennsylvania, Lehigh and Upper Bucks.

* WHEN...From 8 PM this evening to 10 AM EST Thursday.

* IMPACTS...Very slippery sidewalks, roads and bridges are
  possible. The hazardous conditions could impact the morning
  commute. Isolated power outages will be possible.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along 
  and north of the Interstate 78 corridor. South of the 
  Interstate 78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

PAZ060-061000-
/O.CON.KPHI.WW.Y.0004.200206T0100Z-200206T1500Z/
Berks-
Including the city of Reading
304 PM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 10 AM EST THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of 
  around one tenth of an inch.

* WHERE...Berks.

* WHEN...From 8 PM this evening to 10 AM EST Thursday.

* IMPACTS...Very slippery sidewalks, roads and bridges are 
  possible. The hazardous conditions could impact the morning 
  commute.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along 
  and north of the Interstate 78 corridor. South of the 
  Interstate 78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

Deal
749 
WWUS41 KPHI 060135
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
835 PM EST Wed Feb 5 2020

NJZ001-007-008-PAZ054-055-062-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Sussex-Warren-Morris-Carbon-Monroe-Northampton-
Including the cities of Newton, Washington, Morristown, 
Jim Thorpe, Stroudsburg, Bethlehem, and Easton
835 PM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST
THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of one 
  tenth to two tenths of an inch. Locally higher amounts up to 
  three tenths of an inch possible.

* WHERE...Portions of northern New Jersey and east central and 
  northeast Pennsylvania.

* WHEN...Until 10 AM EST Thursday.

* IMPACTS...Difficult travel conditions are possible. The 
  hazardous conditions could impact the morning commute. Isolated 
  to scattered power outages will be possible.

* ADDITIONAL DETAILS...Freezing rain amounts will likely be 
  higher in elevations above 1000 feet however small amounts 
  remain possible down to valley floors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible 
power outages.

The latest road conditions for your state can be obtained by 
calling 5 1 1.

&&

$$

NJZ009-010-PAZ061-105-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Hunterdon-Somerset-Lehigh-Upper Bucks-
Including the cities of Flemington, Somerville, Allentown, 
Chalfont, and Perkasie
835 PM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST 
THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of 
  around one tenth of an inch.

* WHERE...In New Jersey, Hunterdon and Somerset. In Pennsylvania,
  Lehigh and Upper Bucks.

* WHEN...Until 10 AM EST Thursday.

* IMPACTS...Very slippery sidewalks, roads and bridges are 
  possible. The hazardous conditions could impact the morning 
  commute. Isolated power outages will be possible.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along 
  and north of the Interstate 78 corridor. South of the Interstate
  78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible 
power outages.

The latest road conditions for your state can be obtained by 
calling 5 1 1.

&&

$$

PAZ060-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Berks-
Including the city of Reading
835 PM EST Wed Feb 5 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST 
THURSDAY...

* WHAT...Freezing rain expected. Total ice accumulations of 
  around one tenth of an inch.

* WHERE...Berks County.

* WHEN...Until 10 AM EST Thursday.

* IMPACTS...Very slippery sidewalks, roads and bridges are 
  possible. The hazardous conditions could impact the morning 
  commute.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along 
  and north of the Interstate 78 corridor. South of the Interstate
  78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible 
power outages.

The latest road conditions for your state can be obtained by 
calling 5 1 1.

&&

$$
608 
WWUS41 KPHI 060838
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
338 AM EST Thu Feb 6 2020



NJZ009-010-PAZ105-060945-
/O.CAN.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Hunterdon-Somerset-Upper Bucks-
Including the cities of Flemington, Somerville, Chalfont, 
and Perkasie
338 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY IS CANCELLED...

Temperatures across Upper Bucks County in Pennsylvania and
Hunterdon and Somerset Counties in New Jersey are above freezing
and should remain above freezing. Therefore, the threat for
freezing rain has ended and the winter weather advisory has been
cancelled.

$$

NJZ001-007-008-PAZ054-055-062-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Sussex-Warren-Morris-Carbon-Monroe-Northampton-
Including the cities of Newton, Washington, Morristown, 
Jim Thorpe, Stroudsburg, Bethlehem, and Easton
338 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Freezing rain. Additional ice accumulations of around 
  one tenth of an inch.

* WHERE...Portions of northern New Jersey and east central and 
  northeast Pennsylvania.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Difficult travel conditions are possible. The 
  hazardous conditions could impact the morning commute.

* ADDITIONAL DETAILS...Freezing rain amounts will likely be 
  higher in elevations above 1000 feet however small amounts 
  remain possible down to valley floors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

PAZ061-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Lehigh-
Including the city of Allentown
338 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Freezing rain. Additional ice accumulations of a light 
  glaze.

* WHERE...Lehigh.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Very slippery sidewalks, roads and bridges are 
  possible. The hazardous conditions could impact the morning 
  commute.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along 
  and north of the Interstate 78 corridor. South of the Interstate
  78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

PAZ060-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Berks-
Including the city of Reading
338 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Freezing rain. Additional ice accumulations of a light 
  glaze.

* WHERE...Berks.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Very slippery sidewalks, roads and bridges are 
  possible. The hazardous conditions could impact the morning 
  commute.

* ADDITIONAL DETAILS...Freezing rain is primarily expected along 
  and north of the Interstate 78 corridor. South of the Interstate
  78 corridor, freezing rain is less likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

Johnson
442 
WWUS41 KPHI 061125
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
625 AM EST Thu Feb 6 2020



NJZ007-008-PAZ060>062-061230-
/O.CAN.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Warren-Morris-Berks-Lehigh-Northampton-
Including the cities of Washington, Morristown, Reading, 
Allentown, Bethlehem, and Easton
625 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY IS CANCELLED...

Temperatures across Berks, Lehigh, and Northampton Counties in 
Pennsylvania and Warren and Morris Counties in New Jersey are 
above freezing and should remain above freezing. Therefore, the 
threat for freezing rain has ended and the winter weather advisory
has been cancelled.

$$

NJZ001-PAZ054-055-061500-
/O.CON.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Sussex-Carbon-Monroe-
Including the cities of Newton, Jim Thorpe, and Stroudsburg
625 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Freezing rain. Additional ice accumulations of a light 
  glaze.

* WHERE...In New Jersey, Sussex. In Pennsylvania, Carbon and 
  Monroe.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Very slippery sidewalks, roads and bridges are 
  possible. The hazardous conditions could impact the morning 
  commute.

* ADDITIONAL DETAILS...Freezing rain amounts will likely be 
  higher in elevations above 1000 feet however small amounts 
  remain possible down to valley floors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. Prepare for possible
power outages. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

Johnson
009 
WWUS41 KPHI 061500
WSWPHI

URGENT - WINTER WEATHER MESSAGE
National Weather Service Mount Holly NJ
1000 AM EST Thu Feb 6 2020



NJZ001-PAZ054-055-061600-
/O.EXP.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Sussex-Carbon-Monroe-
Including the cities of Newton, Jim Thorpe, and Stroudsburg
1000 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY WILL EXPIRE AT 10 AM EST THIS
MORNING...

While areas of patchy freezing drizzle may still be occur the risk
for additional ice accumulation is no longer expected as
temperatures warm this morning.

$$
Deal
335 
WWUS41 KPHI 061505 CCA
WSWPHI

URGENT - WINTER WEATHER MESSAGE...CORRECTED
National Weather Service Mount Holly NJ
1005 AM EST Thu Feb 6 2020



NJZ001-PAZ054-055-061600-
/O.COR.KPHI.WW.Y.0004.000000T0000Z-200206T1500Z/
Sussex-Carbon-Monroe-
Including the cities of Newton, Jim Thorpe, and Stroudsburg
1005 AM EST Thu Feb 6 2020

...WINTER WEATHER ADVISORY WILL EXPIRE AT 10 AM EST THIS
MORNING...

While areas of patchy freezing drizzle may still be occuring, the
risk for additional ice accumulation is no longer expected as 
temperatures warm this morning.

$$
Deal

What forecasters said that day

The local office's own words before this winter weather advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before this winter weather advisory went out at Feb 4, 6:44 AM EST, 8 hours 10 minutes earlier.

Area forecast discussion, Feb 4, 6:44 AM EST, 8 hours 10 minutes before
Area Forecast Discussion
National Weather Service Mount Holly NJ
644 AM EST Tue Feb 4 2020

.SYNOPSIS...
A weak area of low pressure will track just to our west and north
today, pulling a cold front across the area tonight into early
Wednesday. Another area of low pressure will track up the Ohio
Valley to near the eastern Great Lakes Wednesday night and Thursday
pulling a warm front northward. A stronger low moves up the cold
front and tracks over our area Thursday night into Friday. High
pressure briefly builds in for Saturday followed by a low that may
develop near the Mid-Atlantic coast into Sunday, then a cold front
may arrive later Monday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Today will be the first in a series of systems that will keep cloudy
and at times wet weather in the region for the next several days. A
mid level short wave trough will cross the region through the day
today. There appears to be little in the way of upper level support
(if anything, there is weak ridging from 500 mb and further up), so
not expecting this round to be a soaker. Instead, this looks like a
quick shot for rain showers mostly through the morning, and the
precipitation should be all rain.

One thing of note is that the expected low level jet early this
morning arrived stronger and quicker than what most guidance was
showing. That being said, I don't think this will have a significant
impact for us as the low level jet has already started to weaken
(based on the KDIX VAD wind profile).

Despite the cloudy conditions, we should stay in the warm sector, so
temperatures will remain well above normal (generally 15 to 20
degrees above normal highs for this time of year), with highs in the
upper 40s for the southern Poconos and lower 60s for portions of
northern Delmarva.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
Frontogenesis is expected to occur along the front which will remain
just northwest of our region into early this evening. This will
serve to tighten the temperature gradient across the front and bring
additional chances for precipitation ahead of and with the front as
it begins to sink south through our region overnight. With mostly
zonal flow from about 700 mb and higher, the front is expected to be
shallow and relatively slow moving (relative for most cold fronts in
this region in February). Consequently, the front may not be
completely south of the region/off shore until near sunrise on
Wednesday. Precipitation should end soon after the front passes as
we should see significant dry air advection behind the front.

As for precipitation type with the front, still expect mostly rain
with this front. However, there is a chance if the precipitation
lingers long enough across the southern Poconos and Northwest NJ
there could be a brief period of freezing rain late tonight before
the precipitation comes to an end. For now, think this is unlikely
given the strong dry air advection that is expected. However, given
the shallow and slow moving nature of this front, there is likely to
be a robust warm layer aloft, so if precipitation does hang on
longer than expected, it is probably going to be a question of
freezing rain or rain rather than snow or rain.

Given the timing of the front, we could have a non-diurnal
temperature trend on Wednesday, with the highs being reached early
in the day. Calendar day high temperatures may even occur near or
shortly after midnight. Through the day time on Wednesday,
temperatures will likely be in the 30s and 40s across much of the
region.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Summary...Unsettled with temperature swings due to the arrival of a
few fronts and low pressure systems through late this week. A period
of icing probable Wednesday night and Thursday morning for
portions of eastern Pennsylvania and northwestern New Jersey.

Synoptic Overview...A ridge centered southeast of Florida will give
way to a deep trough marching eastward through late this week. This
will drive several waves of surface low pressure northeastward along
a frontal zone. While a trough remains in the East through the
weekend, it is forecast to weaken quite a bit although a stronger
short wave trough embedded within it may result in a quick surface
low development emerging off the Mid-Atlantic coast during the
second half of the weekend into the start of next week.

For Wednesday night and Thursday...A messy forecast especially due
to parts of the region getting a period of freezing rain/sleet
before going over to rain. Otherwise, a few rounds of rain are
expected. A deep trough is forecast to stretch across the central
part of the country and gradually shift eastward. This will drive
surface low pressure along a frontal zone in the Tennessee and Ohio
valley's. Meanwhile, a front draped across the Mid-Atlantic will
gradually work its way northward in response to increasing flow and
warm air advection. However, surface high pressure to our north
which delivered colder and drier low-level air southward into our
region will give way. A wedge of colder air will take longer to
scour out however across portions of the Poconos to northwestern New
Jersey Thursday. Given the synoptic setup, weighted the forecast
much closer to the NAM which shows a classic warm layer northward
resulting in some sleet to freezing rain. While some snow cannot be
ruled out at the onset up north, this looks like an ice to rain
scenario. Therefore, lowered the snow amounts considerably and went
with more icing. The main area of icing is near and north of I-78
but especially the I-80 corridor. Given the surface low track just
to our west Thursday, the lingering low-level cold air will be
dislodged allowing a change to just rain by early afternoon. There
looks to be a shot of precipitation later Wednesday night and
Thursday morning then possibly a lull for a time Thursday afternoon,
followed by another surge in moisture Thursday night as the main
surface low tracks nearby.

Temperatures will be a challenge as initially the surface warm front
may be slow to advance northward as precipitation arrives within the
remaining wedge setup (lingering confluence as well). The warm front
may take on some coastal front characteristics as warming edges into
southern New Jersey before spreading northwestward. This may result
in much warmer air getting into southern Delaware to southeastern
New Jersey on Thursday.

For Friday...The main upper-level trough arrives in the East and
this drives strengthening low pressure from very near our area to
start the day, then across southeastern New England during the day.
The precipitation will be ending across the area as the storm pulls
away, however it is possible that it ends as a little snow across
the northwestern zones. Otherwise, cold air advection kicks in and
with a tightening pressure gradient an increasing and gusty west to
northwest wind will develop. Rainfall amounts into Friday look to be
1.0 to 2.5 inches as a strong southwesterly low-level jet provides
added lift and a few surges in the precipitable water values reach
1.0 to 1.5 inches.

For Saturday and Sunday...The trough weakens allowing surface high
pressure to build across our area. However, a short wave trough
embedded in the broader trough should induce surface low development
as it crosses the Ohio Valley. This surface low is forecast to
emerge off the Mid-Atlantic coast, however the flow looks
progressive and therefore the storm should quickly shift east and
away from the coast during Sunday. The air mass might be cold enough
for some wintry precipitation on the northwest fringe of the
precipitation shield, however the details on this system is less
certain given the multiple waves occurring before this feature.
Overall, did not make any significant changes during this time frame.

For Monday...The flow aloft is forecast to turn more zonal in the
wake of the weekend short wave trough. Sprawling high pressure
should crest over the area during Monday before shifting offshore at
night. A return flow sets up at night along with warm air advection,
which may result in some showers developing at night. It is possible
the influence of the offshore high pressure remains strong enough to
keep our area dry through the night, as we await for the system well
to our west to get closer. Temperatures still look to be above where
they should be for this time of the year.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Today...Looking upstream, MVFR ceilings aren't as widespread as
I was expecting. Therefore, with the 12Z TAFs, I trended much
more optimistic, keeping most TAF sites with VFR ceilings or
ceilings hovering right around the MVFR/VFR threshold for much
of the day. It should be noted that some guidance (namely the
NAM), does suggest that lower conditions will be possible, but
I'm inclined to doubt that until I see it develop upstream.
Rain showers are possible through the morning, which could lead
to temporary visibility restrictions. Southwesterly winds less
than 10 kt are expected through the day.

Tonight...Ceilings are likely to remain in the MVFR category, though
localized IFR conditions are possible especially with any areas of
rain right along and ahead of the cold front. The cold front will
bring an abrupt shift to northwesterly and eventually northerly
winds between 03 and 09Z. Gusts up to 20 kt are possible just behind
the front. Low confidence on IFR conditions developing, but moderate
confidence on other aspects of the forecast.

Wednesday...Through the day, ceilings are likely to improve to VFR
conditions, though should stay around 5000 ft AGL. Northeasterly
winds near or below 10 kt. Moderate confidence.

Outlook...
Wednesday night through Friday...MVFR/IFR conditions are expected to
prevail through Thursday night, then improvement occurs Friday as a
storm system moves away. Periods of rain, which then ends Friday.
Some sleet and freezing rain should occur at the onset later
Wednesday night for RDG to ABE. Northeast to east winds 5-10 knots
become southeasterly Thursday especially from the PHL area south and
eastward, then southerly Thursday night. Winds shift to the west and
northwest Friday and increase to around 15 knots with gusts to 20-30
knots. High confidence in sub-VFR conditions; low confidence in
winds especially prior to Friday.

Saturday...VFR with increasing clouds. West to southwest winds less
than 10 knots. Moderate confidence.

&&

.MARINE...
Winds and seas will stay below Small Craft Advisory through the day
today. Overnight, a cold front will bring an abrupt shift to
northwesterly winds, and wind gusts above 20 kt are likely behind
the front, especially on the Atlantic Coastal Waters. For now
though, it looks like conditions may remain just below SCA criteria
overnight.

Wednesday...SCA conditions are possible as waves could build above 5
feet on the Atlantic Coastal Waters along with continued
northwesterly wind gusts near 25 kt.

Outlook...
Wednesday night and Thursday...Winds should gust to around 25
knots at times, however warmer air will be over cooler waters.
Seas should build to 4-6 feet mainly on the Atlantic coastal
waters.

Friday and Saturday...Small Craft Advisory probable; low end gales
possible with offshore flow. Winds then diminish later Friday night
and Saturday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.

&&

Synopsis...Gorse
Near Term...Johnson
Short Term...Johnson
Long Term...Gorse
Aviation...Gorse/Johnson
Marine...Gorse/Johnson
Hazardous weather outlook, Feb 4, 3:46 AM EST, 11 hours 8 minutes before
Hazardous Weather Outlook
National Weather Service Mount Holly NJ
346 AM EST Tue Feb 4 2020

NJZ001-007>009-PAZ054-055-060>062-103-105-050900-
Sussex-Warren-Morris-Hunterdon-Carbon-Monroe-Berks-Lehigh-
Northampton-Western Montgomery-Upper Bucks-
346 AM EST Tue Feb 4 2020

This Hazardous Weather Outlook is for northern New Jersey,
northwest New Jersey, east central Pennsylvania, northeast
Pennsylvania and southeast Pennsylvania.

.DAY ONE...Today and tonight.

The probability of widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

A period of sleet and freezing rain Wednesday and Thursday morning
may result in areas of hazardous travel. The greatest chance for a
period of icing looks to be the I-80 corridor.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.

DEZ001>004-MDZ008-012-015-019-020-NJZ010-012>027-PAZ070-071-101-102-
104-106-050900-
New Castle-Kent-Inland Sussex-Delaware Beaches-Cecil-Kent MD-
Queen Annes-Talbot-Caroline-Somerset-Middlesex-Western Monmouth-
Eastern Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-Coastal Ocean-
Southeastern Burlington-Delaware-Philadelphia-Western Chester-
Eastern Chester-Eastern Montgomery-Lower Bucks-
346 AM EST Tue Feb 4 2020

This Hazardous Weather Outlook is for central Delaware, northern
Delaware, southern Delaware, northeast Maryland, central New
Jersey, northern New Jersey, southern New Jersey and southeast
Pennsylvania.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.

ANZ430-431-450>455-050900-
Delaware Bay waters north of East Point NJ to Slaughter Beach DE-
Delaware Bay waters south of East Point NJ to Slaughter Beach DE-
Coastal waters from Sandy Hook to Manasquan Inlet NJ out 20 nm-
Coastal waters from Manasquan Inlet to Little Egg Inlet NJ out 20 nm-
Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 nm-
Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm-
Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm-
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm-
346 AM EST Tue Feb 4 2020

This Hazardous Weather Outlook is for Atlantic coastal waters and
Delaware Bay Waters.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

A period of low-end west-northwest gales are possible Friday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 4, 3:32 PM ESTSmall Craft AdvisoryPHI27 hr

Nearby

Winter Weather Advisories in Pennsylvania, 2020Winter Weather Advisories in New Jersey, 2020Every winter weather advisory in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.