Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 80, NWS Philadelphia/Mount Holly

August 17, 2018Monroe County, Northampton County, Pennsylvania; Sussex County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 17, 2018, 6:22 PM EDT for Monroe County, Northampton County, Pennsylvania; Sussex County, Warren County, New Jersey. It was in force for 38 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 17, 2018, 6:22 PM EDT (22:22 UTC)
Expired
Aug 17, 2018, 7:00 PM EDT
In force
38 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.88 in
Wind
70.0 mph

Counties Sussex County, NJ, Warren County, NJ, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 134 km from the middle of the area, began a volume at 22:22 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.

What was reported inside it

TimeReportWhereRemark
Aug 17, 6:30 PM EDTTSTM WND DMGUpper Mount Bethel Twp, PASEVERAL TREES DOWN IN UPPER MOUNT BETHEL TWP AND EAST BANGOR. TIME ESTIMATED FROM RADAR.
Aug 17, 6:34 PM EDTTSTM WND DMGBelvidere, NJREPORTS OF A FEW TREES AND LARGE BRANCHES DOWN IN BELVIDERE. TIME ESTIMATED FROM RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 17, 3:44 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.4 hours before the alert went out and 174 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 2018-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 321 joules per kilogram.LCLLFCEL10008507005003002001001 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 2018-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 square meters per square second.1939Sfc1 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
321 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
1245 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

053 
WUUS51 KPHI 172222
SVRPHI
NJC037-041-PAC089-095-172300-
/O.NEW.KPHI.SV.W.0080.180817T2222Z-180817T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
622 PM EDT FRI AUG 17 2018

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Western Sussex County in northwestern New Jersey...
  Northern Warren County in northwestern New Jersey...
  Southeastern Monroe County in northeastern Pennsylvania...
  Northeastern Northampton County in eastern Pennsylvania...

* Until 700 PM EDT.

* At 621 PM EDT, a severe thunderstorm was located over East Bangor,
  or 14 miles north of Easton, moving northeast at 40 mph.

  HAZARD...70 mph wind gusts and nickel size hail.

  SOURCE...Public. Several reports of wind damage have been received 
           from Northampton County during the past 20 minutes.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Newton, East Stroudsburg, Blairstown, Bangor, Belvidere, Hope, East
  Bangor, Branchville, Andover, Stormville, Lake Mohawk, Werry Lake,
  Greendell, Millbrook, Delaware Water Gap, Crandon Lakes,
  Flatbrookville, Five Points, Columbia and Echo Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4103 7458 4079 7514 4095 7532 4113 7507
      4108 7503 4112 7495 4118 7488 4121 7486
      4124 7486 4126 7484
TIME...MOT...LOC 2221Z 233DEG 33KT 4090 7519 

HAIL...0.88IN
WIND...70MPH
 
$$

CMS
2 follow-up statements
232 
WWUS51 KPHI 172241
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
641 PM EDT FRI AUG 17 2018

PAC095-172250-
/O.CAN.KPHI.SV.W.0080.000000T0000Z-180817T2300Z/
Northampton PA-
641 PM EDT FRI AUG 17 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN NORTHAMPTON
COUNTY IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 1100 PM EDT for
northwestern New Jersey...and eastern and northeastern Pennsylvania.

LAT...LON 4103 7458 4081 7510 4083 7508 4085 7510
      4085 7507 4087 7505 4096 7513 4095 7518
      4104 7520 4113 7507 4108 7503 4109 7500
      4116 7490 4126 7484
TIME...MOT...LOC 2240Z 233DEG 33KT 4101 7500 

$$

NJC037-041-PAC089-172300-
/O.CON.KPHI.SV.W.0080.000000T0000Z-180817T2300Z/
Sussex NJ-Warren NJ-Monroe PA-
641 PM EDT FRI AUG 17 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR WESTERN SUSSEX...NORTHERN WARREN AND EAST CENTRAL MONROE
COUNTIES...

At 640 PM EDT, a severe thunderstorm was located over Blairstown, or
13 miles west of Newton, moving northeast at 40 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated. This storm has a history of producing wind 
         damage across much of Northampton County.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Newton, East Stroudsburg, Blairstown, Belvidere, Hope, Branchville,
Andover, Flatbrookville, Lake Mohawk, Werry Lake, Greendell,
Millbrook, Delaware Water Gap, Five Points, Columbia, Crandon Lakes,
Echo Lake, Allamuchy-Panther Valley, Stroudsburg and Portland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4103 7458 4081 7510 4083 7508 4085 7510
      4085 7507 4087 7505 4096 7513 4095 7518
      4104 7520 4113 7507 4108 7503 4109 7500
      4116 7490 4126 7484
TIME...MOT...LOC 2240Z 233DEG 33KT 4101 7500 

HAIL...0.75IN
WIND...70MPH
 
$$

CMS
383 
WWUS51 KPHI 172256
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
656 PM EDT FRI AUG 17 2018

NJC037-041-PAC089-172306-
/O.EXP.KPHI.SV.W.0080.000000T0000Z-180817T2300Z/
Sussex NJ-Warren NJ-Monroe PA-
656 PM EDT FRI AUG 17 2018

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN SUSSEX...NORTHERN
WARREN AND EAST CENTRAL MONROE COUNTIES WILL EXPIRE AT 700 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

A severe thunderstorm watch remains in effect until 1100 PM EDT for
northwestern New Jersey...and eastern and northeastern Pennsylvania.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
in Mount Holly NJ.

LAT...LON 4103 7458 4081 7510 4083 7508 4085 7510
      4085 7507 4087 7505 4096 7513 4095 7518
      4104 7520 4113 7507 4108 7503 4109 7500
      4116 7490 4126 7484
TIME...MOT...LOC 2256Z 233DEG 33KT 4109 7486 

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 2:21 PM EDTSpecial Weather StatementPHILehigh24 min
Aug 17, 4:29 PM EDTSpecial Weather StatementPHIBerks46 min
Aug 17, 5:07 PM EDTSpecial Weather StatementPHIBerks, Lehigh53 min
Aug 17, 5:12 PM EDTSpecial Weather StatementPHIBerks33 min
Aug 17, 5:36 PM EDTSpecial Weather StatementPHILehigh, Northampton39 min
Aug 17, 5:59 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton31 min
Aug 17, 6:00 PM EDTSpecial Weather StatementPHICarbon30 min
Aug 17, 6:18 PM EDTSpecial Weather StatementPHIBerks27 min
Aug 17, 6:19 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe41 min
Aug 17, 6:23 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh52 min
Aug 17, 6:40 PM EDTFlash Flood WarningPHIBerks2 hr
Aug 17, 7:09 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more51 min
Aug 17, 7:15 PM EDTSpecial Weather StatementPHIPike15 min
Aug 17, 7:34 PM EDTSpecial Weather StatementPHICarbon26 min
Aug 17, 7:39 PM EDTSpecial Weather StatementPHIMonroe51 min
Aug 17, 7:42 PM EDTSpecial Weather StatementPHIBucks, Northampton33 min
Aug 17, 3:37 PM EDTSpecial Weather StatementPHIHunterdon38 min
Aug 17, 3:42 PM EDTSpecial Weather StatementPHIWarren48 min
Aug 17, 5:46 PM EDTSpecial Weather StatementPHIMorris14 min
Aug 17, 6:02 PM EDTSpecial Weather StatementPHIMorris13 min
Aug 17, 6:59 PM EDTSpecial Weather StatementPHISussex31 min
Aug 17, 7:28 PM EDTSpecial Weather StatementPHISussex17 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2018Severe Thunderstorm Warnings in New Jersey, 2018Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.