Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 159, NWS Philadelphia/Mount Holly

July 7, 2011Carbon County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 7, 2011, 9:47 PM EDT for Carbon County, Lehigh County, Northampton County, Pennsylvania. It was in force for 73 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: Jul 7, 2011, 9:47 PM EDT (01:47 UTC)
Expired: Jul 7, 2011, 11:00 PM EDT
In force: 73 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

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

The radar

The Philadelphia radar (KDIX), 134 km from the middle of the area, began a volume at 01:49 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
Jul 7, 9:50 PM EDT	HAIL 0.5	Summit Hill, PA
Jul 7, 10:48 PM EDT	TSTM WND DMG	Laurys Station, PA	TREES DOWN IN THE SOUTHBOUND LANE OF ROUTE 145

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 1.8 hours before the alert went out and 233 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: 1372 J/kg
Mixed-layer CIN: -44 J/kg
Mixed-layer LCL: 1024 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 69 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

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

877 
WUUS51 KPHI 080147
SVRPHI
PAC025-077-095-080300-
/O.NEW.KPHI.SV.W.0159.110708T0147Z-110708T0300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
947 PM EDT THU JUL 7 2011

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...
  SOUTHERN CARBON COUNTY IN NORTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF LEHIGHTON...

* UNTIL 1100 PM EDT

* AT 944 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
  NEW MAHONING...OR 7 MILES WEST OF LEHIGHTON...AND MOVING SOUTHEAST
  AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  LEHIGHTON AROUND 955 PM EDT...
  JORDAN VALLEY AND NEW TRIPOLI AROUND 1005 PM EDT...
  EMERALD AROUND 1010 PM EDT...
  SLATINGTON AND WALNUTPORT AROUND 1015 PM EDT...
  NEFFS AND SCHNECKSVILLE AROUND 1020 PM EDT...
  COFFEETOWN AROUND 1025 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.

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.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...HEAVY RAIN WILL OCCUR
WITH THESE STORMS AND CAUSE LOW-LYING AND POOR DRAINAGE FLOODING.

&&

LAT...LON 4063 7522 4043 7550 4071 7584 4074 7578
      4079 7585 4082 7589 4092 7574
TIME...MOT...LOC 0147Z 300DEG 23KT 4080 7584

$$
NIERENBERG

3 follow-up statements

130 
WWUS51 KPHI 080236
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1036 PM EDT THU JUL 7 2011

PAC025-080247-
/O.CAN.KPHI.SV.W.0159.000000T0000Z-110708T0300Z/
CARBON PA-
1036 PM EDT THU JUL 7 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CARBON COUNTY IS
CANCELLED...

THE STORM THAT PROMPTED THE WARNING HAS EXITED THE COUNTY.

LAT...LON 4063 7522 4043 7550 4071 7584 4074 7578
      4081 7554
TIME...MOT...LOC 0237Z 300DEG 23KT 4064 7548

$$

PAC077-095-080300-
/O.CON.KPHI.SV.W.0159.000000T0000Z-110708T0300Z/
LEHIGH PA-NORTHAMPTON PA-
1036 PM EDT THU JUL 7 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR SOUTHWESTERN NORTHAMPTON AND LEHIGH COUNTIES...

AT 1035 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 HOKENDAUQUA...OR NEAR ALLENTOWN...MOVING SOUTHEAST AT 25
MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  7 MILES NORTHEAST OF EMMAUS BY 1045 PM EDT...
  FOUNTAIN HILL...BETHLEHEM AND FREEMANSBURG BY 1050 PM EDT...
  HELLERTOWN AND COOPERSBURG BY 1055 PM EDT...

LAT...LON 4063 7522 4043 7550 4071 7584 4074 7578
      4081 7554
TIME...MOT...LOC 0237Z 300DEG 23KT 4064 7548

$$

HAYES

350 
WWUS51 KPHI 080247
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1047 PM EDT THU JUL 7 2011

PAC077-095-080300-
/O.CON.KPHI.SV.W.0159.000000T0000Z-110708T0300Z/
LEHIGH PA-NORTHAMPTON PA-
1047 PM EDT THU JUL 7 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR SOUTHWESTERN NORTHAMPTON AND NORTHEASTERN LEHIGH COUNTIES...

AT 1044 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.
THIS STORM WAS LOCATED NEAR WALNUTPORT...OR 10 MILES NORTH OF 
ALLENTOWN...MOVING EAST AT 20 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  NORTHAMPTON...BEERSVILLE...COPLAY AND NORTH CATASAUQUA BY 1055 PM
  EDT...
  CATASAUQUA...7 MILES NORTHWEST OF BETHLEHEM...8 MILES NORTHWEST OF
  FOUNTAIN HILL AND 8 MILES NORTHWEST OF FREEMANSBURG BY 1100 PM
  EDT...

LAT...LON 4063 7522 4053 7535 4050 7540 4067 7567
      4076 7568 4079 7559 4080 7553
TIME...MOT...LOC 0247Z 285DEG 16KT 4072 7553

$$

HAYES

809 
WWUS51 KPHI 080258
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1058 PM EDT THU JUL 7 2011

PAC077-095-080308-
/O.EXP.KPHI.SV.W.0159.000000T0000Z-110708T0300Z/
LEHIGH PA-NORTHAMPTON PA-
1058 PM EDT THU JUL 7 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN NORTHAMPTON AND
NORTHEASTERN LEHIGH COUNTIES WILL EXPIRE AT 1100 PM EDT...

LAT...LON 4063 7522 4054 7536 4050 7540 4067 7567
      4076 7568 4079 7559 4080 7553
TIME...MOT...LOC 0258Z 285DEG 16KT 4071 7547

$$

HAYES

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 7, 8:56 PM EDT	Special Weather Statement	PHI	Carbon	94 min
Jul 7, 9:10 PM EDT	Severe Thunderstorm Warning	PHI	Carbon	67 min
Jul 7, 10:55 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh, Northampton	28 min
Jul 8, 2:40 AM EDT	Special Weather Statement	PHI	Berks	65 min
Jul 8, 3:58 AM EDT	Flash Flood Watch	PHI	Berks, Carbon, Delaware, Lehigh, Monroe, Northampton and 1 more	19 hr
Jul 8, 12:56 PM EDT	Special Weather Statement	PHI	Philadelphia	64 min
Jul 8, 2:12 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	93 min
Jul 8, 2:23 PM EDT	Special Weather Statement	PHI	Monroe, Northampton	82 min
Jul 8, 2:25 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	7 hr
Jul 8, 2:48 PM EDT	Severe Thunderstorm Warning	PHI	Monroe	57 min
Jul 8, 2:51 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	54 min
Jul 8, 2:56 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Montgomery	3 hr
Jul 8, 3:35 PM EDT	Special Weather Statement	PHI	Montgomery	55 min
Jul 8, 3:40 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh, Northampton	3 hr
Jul 8, 3:44 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Carbon, Lehigh, Monroe, Montgomery and 1 more	76 min
Jul 8, 3:45 PM EDT	Flash Flood Warning	PHI	Philadelphia	3 hr
Jul 8, 4:18 PM EDT	Flash Flood Warning	PHI	Monroe	2 hr
Jul 8, 4:29 PM EDT	Areal Flood Advisory	PHI	Chester	4 hr
Jul 8, 5:33 PM EDT	Areal Flood Advisory	PHI	Bucks	3 hr
Jul 8, 5:44 PM EDT	Flash Flood Warning	PHI	Delaware, Philadelphia	3 hr

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.