Alert archive / Pennsylvania / Snow Squall Warnings in 2018

Snow Squall Warning 1, NWS Philadelphia/Mount Holly

November 21, 2018Carbon County, Monroe County, Pennsylvania; Sussex County, New Jersey

NWS Philadelphia/Mount Holly issued this snow squall warning at Nov 21, 2018, 4:24 PM EST for Carbon County, Monroe County, Pennsylvania; Sussex County, New Jersey. It was in force for 66 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
Nov 21, 2018, 4:24 PM EST (21:24 UTC)
Expired
Nov 21, 2018, 5:30 PM EST
In force
66 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Sussex County, NJ, Carbon County, PA, Monroe County, PA

The radar

The Binghamton radar (KBGM), 139 km from the middle of the area, began a volume at 21:27 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, 9.4 hours before the alert went out and 195 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 2018-11-21Temperature 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 2018-11-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 square meters per square second.1939587897Sfc1 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
1210 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

959 
WWUS51 KPHI 212126
SQWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Snow Squall Warning
National Weather Service Mount Holly NJ
424 PM EST Wed Nov 21 2018

NJC037-PAC025-089-212230-
/O.NEW.KPHI.SQ.W.0001.181121T2124Z-181121T2230Z/
Sussex NJ-Carbon PA-Monroe PA-
424 PM EST Wed Nov 21 2018

The National Weather Service in Mount Holly NJ has issued a

* Snow Squall Warning for...
  Northern Sussex County in northwestern New Jersey...
  Carbon County in northeastern Pennsylvania...
  Monroe County in northeastern Pennsylvania...

* Until 530 PM EST.

* At 424 PM EST, a dangerous snow squall was located along a line
  extending from near Oakland to near Blooming Grove to Sterling to 6
  miles southeast of Glendale to Luzerne to Waller, moving southeast
  at 30 mph.

  HAZARD...Extremely poor visibility in heavy snow and blowing snow. 
           Wind gusts up to 30 mph.

  SOURCE...Radar indicated.

  IMPACT...Dangerous life-threatening travel.

* This will impact portions of Interstate 80, 380 and 476.

Locations impacted include...
Port Jervis, Mount Pocono, East Stroudsburg, Tobyhanna, Jim Thorpe,
Weatherly, Sussex, Branchville, Unionville, Stormville, High Point,
Werry Lake, Pocono Pines, Lake Harmony, Vernon Valley, Skytop,
Tannersville, Long Pond, Kresgeville and Sun Valley.

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.

Reduce your speed and turn on headlights! During snow squalls, the
visibility may suddenly drop to near zero in whiteout conditions.

&&

LAT...LON 4124 7443 4116 7471 4105 7492 4109 7496
      4095 7515 4083 7538 4081 7550 4093 7595
      4101 7573 4109 7577 4113 7569 4112 7564
      4123 7554 4125 7513 4115 7515 4114 7509
      4108 7503 4116 7490 4135 7475 4136 7469
TIME...MOT...LOC 2124Z 308DEG 25KT 4146 7469 4140 7511 4133 7542 4126
7564 4130 7590 4124 7642

$$

Gorse
1 follow-up statement
013 
WWUS51 KPHI 212159
SQWPHI

Snow Squall Warning
National Weather Service Mount Holly NJ
457 PM EST Wed Nov 21 2018

NJC037-PAC025-089-212230-
/O.CON.KPHI.SQ.W.0001.000000T0000Z-181121T2230Z/
Sussex NJ-Carbon PA-Monroe PA-
457 PM EST Wed Nov 21 2018

...A SNOW SQUALL WARNING REMAINS IN EFFECT UNTIL 530 PM EST FOR
NORTHERN SUSSEX...CARBON AND MONROE COUNTIES...

At 457 PM EST, a dangerous snow squall was located along a line
extending from near Unionville to Dingmans Ferry to near Alpine
Mountain to near Long Pond to near Stoddartsville to near Berwick,
moving southeast at 30 mph.

HAZARD...Extremely poor visibility heavy snow and blowing snow. Wind 
         gusts up to 30 mph.

SOURCE...Radar indicated.

IMPACT...Dangerous life-threatening travel.

This will impact portions of Interstate 80, 380 and 476, with the 
greatest impacts expected in areas where temperatures drop to near 
or below freezing.

Locations impacted include...
Port Jervis, Mount Pocono, East Stroudsburg, Tobyhanna, Jim Thorpe,
Weatherly, Sussex, Branchville, Unionville, Stormville, High Point,
Werry Lake, Pocono Pines, Lake Harmony, Vernon Valley, Skytop,
Tannersville, Long Pond, Kresgeville and Sun Valley.

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.

Reduce your speed and turn on headlights! During snow squalls, the
visibility may suddenly drop to near zero in whiteout conditions.

&&

LAT...LON 4124 7443 4116 7471 4105 7492 4109 7496
      4095 7515 4083 7538 4081 7550 4093 7595
      4101 7573 4109 7577 4113 7569 4112 7564
      4123 7554 4125 7513 4115 7515 4114 7509
      4108 7503 4116 7490 4135 7475 4136 7469
TIME...MOT...LOC 2157Z 312DEG 27KT 4131 7448 4122 7486 4114 7518 4108
7542 4116 7567 4110 7628

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 21, 5:28 PM ESTSnow Squall WarningPHICarbon, Monroe, Northampton62 min
Nov 21, 6:22 PM ESTSpecial Weather StatementPHINorthampton53 min

Nearby

Snow Squall Warnings in Pennsylvania, 2018Snow Squall Warnings in New Jersey, 2018Every snow squall warning in 2018

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.