Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 12, NWS Philadelphia/Mount Holly

May 24, 2012Bucks County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 24, 2012, 3:16 PM EDT for Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 59 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
May 24, 2012, 3:16 PM EDT (19:16 UTC)
Expired
May 24, 2012, 4:15 PM EDT
In force
59 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Bucks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 122 km from the middle of the area, began a volume at 19:16 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
May 24, 3:28 PM EDTTSTM WND DMGWhitehall Twp, PALARGE TREE LIMBS DOWN AND ONE TREE DOWN IN THE WHITEHALL... SOUTH WHITEHALL AND CATASAUQUA AREA OF LEHIGH COUNTY.
May 24, 3:30 PM EDTHAIL 0.75Emmaus, PA

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

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 7.3 hours before the alert went out and 144 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 2012-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 302 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 2012-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -11 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
302 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
499 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-11 m²/s²
0-3 km storm-relative helicity
6 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

657 
WUUS51 KPHI 241916
SVRPHI
PAC017-077-095-242015-
/O.NEW.KPHI.SV.W.0012.120524T1916Z-120524T2015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
316 PM EDT THU MAY 24 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF ALLENTOWN...
  SOUTHWESTERN NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 415 PM EDT

* AT 312 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS TO 60 MPH.  THIS STORM WAS LOCATED 7 MILES
  SOUTH OF PLEASANT VALLEY...OR 15 MILES SOUTHEAST OF ALLENTOWN...AND
  MOVING NORTHWEST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  PLEASANT VALLEY AROUND 325 PM EDT...
  EMMAUS AND HELLERTOWN AROUND 335 PM EDT...
  EMMAUS AROUND 340 PM EDT...
  ALLENTOWN AND BETHLEHEM AROUND 345 PM EDT...
  NORTHAMPTON AND COFFEETOWN AROUND 355 PM EDT...
  NEFFS AND BEERSVILLE AROUND 405 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 4082 7541 4077 7537 4055 7520 4039 7543
      4039 7544 4046 7556 4071 7581 4078 7568
      4079 7560 4081 7554 4082 7543
TIME...MOT...LOC 1915Z 150DEG 24KT 4043 7534

$$

TFG
2 follow-up statements
717 
WWUS51 KPHI 241944
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
344 PM EDT THU MAY 24 2012

PAC017-241953-
/O.CAN.KPHI.SV.W.0012.000000T0000Z-120524T2015Z/
BUCKS PA-
344 PM EDT THU MAY 24 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN BUCKS COUNTY IS
CANCELLED...

THE SEVERE THUNDERSTORM MOVED NORTH OF THE COUNTY. DO NOT DRIVE 
AROUND BARRICADES. 

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

LAT...LON 4061 7525 4049 7550 4048 7558 4071 7581
      4076 7570 4078 7568 4078 7563 4081 7554
      4081 7550 4082 7541
TIME...MOT...LOC 1943Z 150DEG 24KT 4050 7556 4067 7530

$$

PAC077-095-242015-
/O.CON.KPHI.SV.W.0012.000000T0000Z-120524T2015Z/
LEHIGH PA-NORTHAMPTON PA-
344 PM EDT THU MAY 24 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR SOUTHWESTERN NORTHAMPTON AND LEHIGH COUNTIES...

AT 342 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS TO 60 MPH.  THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM MACUNGIE TO FREEMANSBURG...
OR ALONG A LINE EXTENDING FROM 7 MILES SOUTHWEST OF ALLENTOWN TO
EASTON...MOVING NORTHWEST AT 30 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  ANCIENT OAKS AND ALLENTOWN BY 350 PM EDT...
  NORTH CATASAUQUA...HOKENDAUQUA...FULLERTON AND CATASAUQUA BY 355 PM
  EDT...
  COFFEETOWN...NORTHAMPTON...COPLAY AND CHAPMAN BY 400 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM HAS A HISTORY OF PRODUCING DESTRUCTIVE WINDS AND LARGE
DAMAGING HAIL. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY
AWAY FROM WINDOWS!

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 4061 7525 4049 7550 4048 7558 4071 7581
      4076 7570 4078 7568 4078 7563 4081 7554
      4081 7550 4082 7541
TIME...MOT...LOC 1943Z 150DEG 24KT 4050 7556 4067 7530

$$

TFG
252 
WWUS51 KPHI 242004
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
404 PM EDT THU MAY 24 2012

PAC077-095-242015-
/O.CON.KPHI.SV.W.0012.000000T0000Z-120524T2015Z/
LEHIGH PA-NORTHAMPTON PA-
404 PM EDT THU MAY 24 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR WEST CENTRAL NORTHAMPTON AND LEHIGH COUNTIES...

AT 359 PM EDT...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED CAPABLE
OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS TO 60
MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM
CLAUSSVILLE TO CHAPMAN...OR ALONG A LINE EXTENDING FROM 9 MILES WEST
OF ALLENTOWN TO 10 MILES NORTHWEST OF EASTON...MOVING NORTHWEST AT 30
MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  NEFFS AND SCHNECKSVILLE BY 410 PM EDT...
  SLATINGTON...EMERALD...NEW TRIPOLI AND JORDAN VALLEY BY 415 PM
  EDT...

IF YOU SEE THREATENING WEATHER, PLEASE SEEK SHELTER IMMEDIATELY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 4081 7540 4074 7535 4054 7564 4071 7581
      4073 7577 4073 7575 4078 7568 4078 7562
      4081 7554 4082 7544
TIME...MOT...LOC 2003Z 150DEG 24KT 4060 7567 4078 7541

$$

TFG

The office that day

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

IssuedProductOfficeCountiesLasted
May 24, 1:47 PM EDTSevere Thunderstorm WarningPHIBucks43 min
May 24, 1:57 PM EDTSpecial Weather StatementPHIDelaware, Philadelphia63 min
May 24, 2:01 PM EDTAreal Flood AdvisoryPHIBucks, Chester, Delaware, Montgomery, Philadelphia83 min
May 24, 2:08 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery52 min
May 24, 2:21 PM EDTAreal Flood AdvisoryPHIBucks, Montgomery97 min
May 24, 2:26 PM EDTSpecial Weather StatementPHIDelaware, Montgomery64 min
May 24, 2:32 PM EDTSevere Thunderstorm WarningPHIBucks29 min
May 24, 2:36 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery54 min
May 24, 3:09 PM EDTSpecial Weather StatementPHIBerks, Lehigh66 min
May 24, 3:13 PM EDTAreal Flood AdvisoryPHIBucks, Lehigh, Northampton91 min
May 24, 3:38 PM EDTSpecial Weather StatementPHINorthampton67 min
May 24, 3:39 PM EDTAreal Flood AdvisoryPHIBerks, Montgomery57 min
May 24, 4:00 PM EDTAreal Flood AdvisoryPHICarbon, Monroe67 min
May 24, 4:07 PM EDTSpecial Weather StatementPHICarbon, Monroe83 min
May 24, 4:23 PM EDTSpecial Weather StatementPHIMonroe97 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2012Every severe thunderstorm warning in 2012

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.