Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 17, NWS Philadelphia/Mount Holly

May 27, 2015Burlington County, Camden County, Gloucester County, New Jersey; 5 counties in Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 27, 2015, 5:25 PM EDT for Burlington County, Camden County, Gloucester County, New Jersey; 5 counties in Pennsylvania; New Castle County, Delaware. It was in force for 44 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
May 27, 2015, 5:25 PM EDT (21:25 UTC)
Expired
May 27, 2015, 6:09 PM EDT
In force
44 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 57 km from the middle of the area, began a volume at 21:28 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 watch it was issued in

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

IssuedProductOfficeLasted
May 27, 12:54 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.4 hours before the alert went out and 106 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, Phillips Aaf/Abe, MD at 12:00Z on 2015-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 428 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, Phillips Aaf/Abe, MD at 12:00Z on 2015-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 78 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
428 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
589 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
81 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

880 
WUUS51 KPHI 272125
SVRPHI
DEC003-NJC005-007-015-PAC017-029-045-091-101-272230-
/O.NEW.KPHI.SV.W.0017.150527T2125Z-150527T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
525 PM EDT WED MAY 27 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  NORTHWESTERN BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...
  NORTHWESTERN GLOUCESTER COUNTY IN SOUTHERN NEW JERSEY...
  NORTHWESTERN CAMDEN COUNTY IN SOUTHERN NEW JERSEY...
  SOUTHEASTERN MONTGOMERY COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  PHILADELPHIA COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  SOUTHEASTERN BUCKS COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  EAST CENTRAL CHESTER COUNTY IN SOUTHEASTERN PENNSYLVANIA...

* UNTIL 630 PM EDT

* AT 524 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS 
  STORM WAS LOCATED OVER GRADYVILLE...PENNSYLVANIA...AND MOVING 
  NORTHEAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  PHILADELPHIA...CAMDEN...GLOUCESTER CITY...BENSALEM...CHESTER...
  WILLINGBORO...FLORENCE...YEADON...WESTTOWN...BURLINGTON...
  BRISTOL...MOUNT HOLLY...RIVERSIDE...CONSHOHOCKEN...PALMYRA...
  HATBORO...FOLCROFT...SWARTHMORE...PAULSBORO AND JENKINTOWN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...DEADLY
LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER
COVERS THE ROAD.

&&

LAT...LON 4003 7468 3977 7549 3991 7561 4027 7493
TIME...MOT...LOC 2124Z 239DEG 38KT 3992 7547 

$$

IOVINO
2 follow-up statements
339 
WWUS51 KPHI 272158
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
558 PM EDT WED MAY 27 2015

DEC003-PAC029-272206-
/O.CAN.KPHI.SV.W.0017.000000T0000Z-150527T2230Z/
NEW CASTLE DE-CHESTER PA-
558 PM EDT WED MAY 27 2015

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN NEW CASTLE AND
EAST CENTRAL CHESTER COUNTIES IS CANCELLED...
    
THE SEVERE THUNDERSTORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF 
NEW CASTLE COUNTY AND CHESTER COUNTY. THEREFORE THE WARNING HAS BEEN 
CANCELLED.

LAT...LON 4003 7468 3981 7538 4004 7536 4027 7493
TIME...MOT...LOC 2156Z 239DEG 38KT 4010 7509 

$$

NJC005-007-015-PAC017-045-091-101-272230-
/O.CON.KPHI.SV.W.0017.000000T0000Z-150527T2230Z/
BURLINGTON NJ-GLOUCESTER NJ-CAMDEN NJ-MONTGOMERY PA-DELAWARE PA-
PHILADELPHIA PA-BUCKS PA-
558 PM EDT WED MAY 27 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR NORTHWESTERN BURLINGTON...NORTHWESTERN GLOUCESTER...NORTHWESTERN
CAMDEN...SOUTHEASTERN MONTGOMERY...EASTERN DELAWARE...PHILADELPHIA
AND SOUTHEASTERN BUCKS COUNTIES...

AT 556 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE
OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS 
LOCATED OVER EASTERN DELAWARE COUNTY...MOVING NORTHEAST AT 40 MPH.

LOCATIONS IMPACTED INCLUDE...
PHILADELPHIA...CAMDEN...GLOUCESTER CITY...BENSALEM...CHESTER...
WILLINGBORO...FLORENCE...YEADON...BURLINGTON...BRISTOL...RIVERSIDE...
CONSHOHOCKEN...PALMYRA...HATBORO...FOLCROFT...SWARTHMORE...
PAULSBORO...JENKINTOWN...WESTVILLE AND NARBERTH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DEADLY LIGHTNING AND 
VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE 
LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS 
QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4003 7468 3981 7538 4004 7536 4027 7493
TIME...MOT...LOC 2156Z 239DEG 38KT 4010 7509 

$$

IOVINO
876 
WWUS51 KPHI 272209
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
609 PM EDT WED MAY 27 2015

NJC005-007-015-PAC017-045-091-101-272218-
/O.CAN.KPHI.SV.W.0017.000000T0000Z-150527T2230Z/
BURLINGTON NJ-GLOUCESTER NJ-CAMDEN NJ-MONTGOMERY PA-DELAWARE PA-
PHILADELPHIA PA-BUCKS PA-
609 PM EDT WED MAY 27 2015

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN BURLINGTON...
NORTHWESTERN GLOUCESTER...NORTHWESTERN CAMDEN...SOUTHEASTERN
MONTGOMERY...EASTERN DELAWARE...PHILADELPHIA AND SOUTHEASTERN BUCKS
COUNTIES IS CANCELLED...
    
THE SEVERE THUNDERSTORM WHICH PROMPTED THE WARNING HAS WEAKENED. 
THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 4003 7468 3981 7538 4004 7536 4027 7493
TIME...MOT...LOC 2205Z 239DEG 38KT 4017 7494 

$$

IOVINO

The office that day

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

IssuedProductOfficeCountiesLasted
May 27, 4:11 AM EDTSmall Craft AdvisoryPHI25 hr
May 27, 5:48 PM EDTSpecial Weather StatementPHIMercer, Middlesex57 min
May 27, 2:23 PM EDTSpecial Weather StatementPHILebanon22 min
May 27, 2:48 PM EDTSpecial Weather StatementPHICarbon27 min
May 27, 2:53 PM EDTSpecial Weather StatementPHIBerks, Lehigh52 min
May 27, 3:06 PM EDTSpecial Weather StatementPHICarbon, Monroe54 min
May 27, 3:13 PM EDTSpecial Weather StatementPHIBerks62 min
May 27, 3:53 PM EDTSpecial Weather StatementPHIMonroe37 min
May 27, 4:26 PM EDTSpecial Weather StatementPHIChester64 min
May 27, 4:36 PM EDTSevere Thunderstorm WarningPHIChester39 min
May 27, 5:07 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery53 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015Severe Thunderstorm Warnings in New Jersey, 2015Severe Thunderstorm Warnings in Delaware, 2015Every severe thunderstorm warning in 2015

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.