Alert archive / Pennsylvania / Snow Squall Warnings in 2020

Snow Squall Warning 16, NWS Philadelphia/Mount Holly

February 29, 20204 counties in Pennsylvania; Morris County, Sussex County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this snow squall warning at Feb 29, 2020, 11:05 AM EST for 4 counties in Pennsylvania; Morris County, Sussex County, Warren County, New Jersey. It was in force for 55 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Feb 29, 2020, 11:05 AM EST (16:05 UTC)
Expired
Feb 29, 2020, 12:00 PM EST
In force
55 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Morris County, NJ, Sussex County, NJ, Warren County, NJ, Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 133 km from the middle of the area, began a volume at 16:04 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, 4.1 hours before the alert went out and 182 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 2020-02-29Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2020-02-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 square meters per square second.19395878Sfc1 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
1458 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
51 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

740 
WWUS51 KPHI 291606
SQWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Snow Squall Warning
National Weather Service Mount Holly NJ
1105 AM EST Sat Feb 29 2020

NJC027-037-041-PAC025-077-089-095-291700-
/O.NEW.KPHI.SQ.W.0016.200229T1605Z-200229T1700Z/
Morris NJ-Sussex NJ-Warren NJ-Lehigh PA-Carbon PA-Monroe PA-
Northampton PA-
1105 AM EST Sat Feb 29 2020

The National Weather Service in Mount Holly NJ has issued a

* Snow Squall Warning for...
  Northern Morris County in northern New Jersey...
  Sussex County in northwestern New Jersey...
  Northern Warren County in northwestern New Jersey...
  Northwestern Lehigh County in eastern Pennsylvania...
  Carbon County in northeastern Pennsylvania...
  Monroe County in northeastern Pennsylvania...
  Northern Northampton County in eastern Pennsylvania...

* Until noon EST.

* At 1105 AM EST, a dangerous snow squall was located along a line
  extending from near Unionville to near Bushkill to near White
  Haven, moving southeast at 25 mph.

  HAZARD...Poor visibility in snow and blowing snow. Wind gusts up 
           to 30 mph.

  SOURCE...Radar and webcams.

  IMPACT...Expect hazardous road conditions.

* This includes the following highways...
   Interstate 80 in New Jersey between mile markers 0 and 35.
   Interstate 80 in Pennsylvania between mile markers 287 and 314.
   Northeast Extension between exits A74 and A87.
   Interstate 380 in Pennsylvania between mile markers 0 and 2.

Locations impacted include...
Newton, Lehighton, Montague, Mount Pocono, Hopatcong, East
Stroudsburg, Hackettstown, Wharton, Blairstown, Palmerton, Bangor,
Mount Arlington, Franklin, Jim Thorpe, Slatington, Stanhope, Pen
Argyl, Nesquehoning, Hamburg and Netcong.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Consider avoiding or delaying travel until the snow squall passes
your location. If you must travel, use extra caution and allow extra
time. Rapid changes in visibility and slick road conditions may lead
to accidents.

&&

LAT...LON 4120 7437 4110 7449 4104 7450 4105 7445
      4101 7437 4101 7435 4090 7457 4070 7578
      4072 7580 4074 7576 4091 7599 4101 7573
      4103 7574 4105 7576 4115 7515 4109 7501
      4116 7490 4128 7484 4135 7475 4136 7469
TIME...MOT...LOC 1605Z 304DEG 22KT 4138 7457 4115 7502 4101 7580 

$$

Staarmann
1 follow-up statement
362 
WWUS51 KPHI 291649
SQWPHI

Snow Squall Warning
National Weather Service Mount Holly NJ
1149 AM EST Sat Feb 29 2020

NJC027-037-041-PAC025-077-089-095-291700-
/O.CON.KPHI.SQ.W.0016.000000T0000Z-200229T1700Z/
Morris NJ-Sussex NJ-Warren NJ-Lehigh PA-Carbon PA-Monroe PA-
Northampton PA-
1149 AM EST Sat Feb 29 2020

...A SNOW SQUALL WARNING REMAINS IN EFFECT UNTIL NOON EST FOR
NORTHERN MORRIS...CENTRAL SUSSEX...NORTHERN WARREN...NORTHWESTERN
LEHIGH...SOUTHEASTERN CARBON...SOUTHWESTERN MONROE AND NORTHERN
NORTHAMPTON COUNTIES...

At 1149 AM EST, a dangerous snow squall was located along a line
extending from near Highland Lake to near Andover to near
Danielsville, moving southeast at 25 mph.

HAZARD...Poor visibility in snow and blowing snow. Wind gusts up to 
         30 mph.

SOURCE...Radar and webcams.

IMPACT...Expect hazardous road conditions.

This includes the following highways...
 Interstate 80 in New Jersey between mile markers 0 and 35.
 Interstate 80 in Pennsylvania between mile markers 310 and 311.
 Northeast Extension near exit A74.

Locations impacted include...
Newton, Lehighton, Hopatcong, East Stroudsburg, Hackettstown,
Wharton, Blairstown, Palmerton, Bangor, Mount Arlington, Franklin,
Jim Thorpe, Slatington, Stanhope, Pen Argyl, Hamburg, Netcong, Wind
Gap, Belvidere and Ogdensburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Consider avoiding or delaying travel until the snow squall passes
your location. If you must travel, use extra caution and allow extra
time. Rapid changes in visibility and slick road conditions may lead
to accidents.

&&

LAT...LON 4077 7580 4083 7579 4091 7571 4104 7483
      4127 7460 4120 7437 4110 7449 4104 7450
      4105 7445 4101 7437 4101 7435 4090 7457
      4070 7578 4072 7580 4074 7576
TIME...MOT...LOC 1649Z 306DEG 22KT 4116 7443 4095 7478 4081 7556 

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 29, 10:21 AM ESTSnow Squall WarningPHICarbon, Monroe39 min
Feb 29, 12:50 PM ESTSpecial Weather StatementPHIWarren25 min
Feb 29, 1:09 PM ESTSpecial Weather StatementPHIMorris36 min
Feb 29, 1:29 PM ESTSpecial Weather StatementPHIWarren46 min

Nearby

Snow Squall Warnings in Pennsylvania, 2020Snow Squall Warnings in New Jersey, 2020Every snow squall warning 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.