Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 64, NWS Philadelphia/Mount Holly

May 23, 20114 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 23, 2011, 7:22 PM EDT for 4 counties in Pennsylvania. It was in force for 38 min. 4 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 23, 2011, 7:22 PM EDT (23:22 UTC)
Expired: May 23, 2011, 8:00 PM EDT
In force: 38 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 128 km from the middle of the area, began a volume at 23:23 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 23, 7:22 PM EDT	TSTM WND DMG	Mahoning Twp, PA	TREES DOWN
May 23, 7:25 PM EDT	TORNADO	Franklin Twp, PA	CONFIRMED EF-0 TORNADO... ONE STRUCTURE EXPERIENCED SIGNIFICANT DAMAGE... NUMEROUS TREES DOWN AND SNAPPED... OTHER STRUCTURES SUFFERED MINOR DAMAGE
May 23, 7:30 PM EDT	TSTM WND DMG	Franklin Twp, PA	TREES DOWN AND ALSO ROOF DAMAGE
May 23, 7:36 PM EDT	TSTM WND DMG	Palmerton, PA	TREES DOWN... FUNNELS SIGHTED ALSO.

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, 11.4 hours before the alert went out and 168 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 530 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: -35 m²/s²
0-3 km storm-relative helicity: 11 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.

083 
WUUS51 KPHI 232322
SVRPHI
PAC025-077-089-095-240000-
/O.NEW.KPHI.SV.W.0064.110523T2322Z-110524T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
722 PM EDT MON MAY 23 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  SOUTHERN CARBON COUNTY IN NORTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF LEHIGHTON...
  SOUTHERN MONROE COUNTY IN NORTHEAST PENNSYLVANIA...

* UNTIL 800 PM EDT

* AT 719 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  JORDAN VALLEY...OR NEAR LEHIGHTON...AND MOVING EAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  WALNUTPORT AROUND 730 PM EDT...
  BEERSVILLE AROUND 735 PM EDT...
  BATH AROUND 740 PM EDT...
  NAZARETH AROUND 745 PM EDT...
  BELFAST...WIND GAP...TATAMY AND PEN ARGYL AROUND 750 PM EDT...
  BANGOR AROUND 755 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES GREATEST KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

&&

LAT...LON 4107 7510 4101 7509 4099 7514 4096 7514
      4091 7508 4085 7506 4084 7510 4079 7510
      4076 7518 4072 7520 4067 7578 4073 7581
      4074 7578 4076 7581 4088 7588
TIME...MOT...LOC 2322Z 265DEG 40KT 4077 7568

$$

PO

1 follow-up statement

566 
WWUS51 KPHI 232343
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
743 PM EDT MON MAY 23 2011

PAC025-077-089-095-240000-
/O.CON.KPHI.SV.W.0064.000000T0000Z-110524T0000Z/
LEHIGH PA-NORTHAMPTON PA-CARBON PA-MONROE PA-
743 PM EDT MON MAY 23 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR SOUTHERN MONROE...SOUTHEASTERN CARBON...NORTHAMPTON AND NORTH
CENTRAL LEHIGH COUNTIES...

AT 740 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE 
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS 
LOCATED NEAR WALNUTPORT...OR 11 MILES SOUTHEAST OF 
LEHIGHTON...MOVING EAST AT 35 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  CHAPMAN...BATH AND 9 MILES SOUTH OF GILBERT BY 755 PM EDT...
  BELFAST...WIND GAP...EASTLAWN GARDENS AND NAZARETH BY 800 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 4107 7510 4101 7509 4099 7514 4096 7514
      4090 7508 4085 7507 4084 7510 4079 7510
      4078 7516 4074 7520 4072 7520 4069 7560
      4080 7568 4094 7562
TIME...MOT...LOC 2343Z 248DEG 32KT 4075 7552

$$
 
TFG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 23, 5:35 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	55 min
May 23, 5:47 PM EDT	Special Weather Statement	PHI	Berks	43 min
May 23, 6:21 PM EDT	Special Weather Statement	PHI	Berks, Chester, Montgomery	54 min
May 23, 6:30 PM EDT	Special Weather Statement	PHI	Carbon, Northampton	60 min
May 23, 7:30 PM EDT	Tornado Warning	PHI	Carbon, Lehigh, Monroe, Northampton	30 min
May 23, 7:58 PM EDT	Tornado Warning	PHI	Bucks, Lehigh, Northampton	32 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.