Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 42, NWS Philadelphia/Mount Holly

May 15, 2011Berks County, Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 15, 2011, 4:19 PM EDT for Berks County, Lehigh County, Pennsylvania. It was in force for 56 min. 1 report 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 15, 2011, 4:19 PM EDT (20:19 UTC)
Expired: May 15, 2011, 5:15 PM EDT
In force: 56 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Berks County, PA, Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 129 km from the middle of the area, began a volume at 20:21 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

Time	Report	Where	Remark
May 15, 4:40 PM EDT	HAIL 0.88	Fogelsville, PA

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.3 hours before the alert went out and 236 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 55 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 545 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 50 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.

547 
WUUS51 KPHI 152019
SVRPHI
PAC011-077-152115-
/O.NEW.KPHI.SV.W.0042.110515T2019Z-110515T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
419 PM EDT SUN MAY 15 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  CENTRAL LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF ALLENTOWN...

* UNTIL 515 PM EDT

* AT 417 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR KUTZTOWN...OR 15 MILES NORTHEAST OF
  READING...AND MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  TOPTON AROUND 430 PM EDT...
  7 MILES NORTHWEST OF ANCIENT OAKS AROUND 500 PM EDT...
  CLAUSSVILLE AROUND 505 PM EDT...
  SCHNECKSVILLE...COFFEETOWN...NEFFS AND 9 MILES WEST OF ALLENTOWN
  AROUND 515 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.

&&

LAT...LON 4073 7561 4059 7542 4042 7575 4054 7591
TIME...MOT...LOC 2019Z 226DEG 10KT 4052 7579

$$

HAYES

2 follow-up statements

778 
WWUS51 KPHI 152041
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
441 PM EDT SUN MAY 15 2011

PAC011-077-152115-
/O.CON.KPHI.SV.W.0042.000000T0000Z-110515T2115Z/
BERKS PA-LEHIGH PA-
441 PM EDT SUN MAY 15 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR CENTRAL LEHIGH AND NORTHEASTERN BERKS COUNTIES...

AT 438 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL.  THIS STORM WAS LOCATED NEAR CLAUSSVILLE...OR 11 MILES WEST OF
ALLENTOWN...MOVING NORTHEAST AT 25 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  COFFEETOWN...SCHNECKSVILLE AND 8 MILES NORTHWEST OF ALLENTOWN BY
  455 PM EDT...
  NEFFS AND FULLERTON BY 500 PM EDT...

LAT...LON 4054 7558 4051 7567 4059 7582 4073 7561
      4059 7542
TIME...MOT...LOC 2041Z 225DEG 22KT 4060 7568

$$

HAYES

866 
WWUS51 KPHI 152107
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
507 PM EDT SUN MAY 15 2011

PAC011-077-152116-
/O.EXP.KPHI.SV.W.0042.000000T0000Z-110515T2115Z/
BERKS PA-LEHIGH PA-
507 PM EDT SUN MAY 15 2011

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL LEHIGH AND
NORTHEASTERN BERKS COUNTIES WILL EXPIRE AT 515 PM EDT...

THE STORM THAT PROMPTED THE WARNING IS MOVING OUT OF THE AREA. 

LAT...LON 4054 7558 4051 7567 4059 7582 4073 7561
      4059 7542
TIME...MOT...LOC 2106Z 225DEG 22KT 4071 7553

$$

HAYES

The office that day

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

Issued	Product	Office	Counties	Lasted
May 14, 11:46 PM EDT	Special Weather Statement	PHI	Berks, Chester, Delaware, Montgomery	89 min
May 15, 12:52 AM EDT	Special Weather Statement	PHI	Bucks, Carbon, Lehigh, Monroe, Montgomery, Northampton and 1 more	83 min
May 15, 2:26 PM EDT	Special Weather Statement	PHI	Berks	64 min
May 15, 2:46 PM EDT	Special Weather Statement	PHI	Schuylkill	59 min
May 15, 2:55 PM EDT	Special Weather Statement	PHI	Delaware	65 min
May 15, 3:30 PM EDT	Special Weather Statement	PHI	Berks	60 min
May 15, 3:37 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	53 min
May 15, 3:39 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	44 min
May 15, 4:14 PM EDT	Special Weather Statement	PHI	Lehigh	61 min
May 15, 4:31 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	59 min
May 15, 4:35 PM EDT	Special Weather Statement	PHI	Lehigh	55 min
May 15, 4:52 PM EDT	Special Weather Statement	PHI	Northampton	68 min
May 15, 5:03 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh, Monroe, Northampton	57 min
May 15, 5:33 PM EDT	Special Weather Statement	PHI	Berks, Carbon, Lehigh	57 min
May 15, 5:37 PM EDT	Special Weather Statement	PHI	Bucks	53 min
May 15, 5:46 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	59 min
May 15, 6:39 PM EDT	Special Weather Statement	PHI	Berks	66 min
May 15, 7:20 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh	3 hr
May 15, 7:28 PM EDT	Special Weather Statement	PHI	Delaware, Montgomery, Philadelphia	62 min
May 15, 7:37 PM EDT	Special Weather Statement	PHI	Berks	53 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2011 Every severe thunderstorm warning in 2011

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.