Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 26, NWS Philadelphia/Mount Holly

May 22, 20144 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 22, 2014, 4:31 PM EDT for 4 counties in Pennsylvania. It was in force for 44 min. 5 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 22, 2014, 4:31 PM EDT (20:31 UTC)
Expired: May 22, 2014, 5:15 PM EDT
In force: 44 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Berks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA

What was reported inside it

Time	Report	Where	Remark
May 22, 5:00 PM EDT	HAIL 1	Lionville, PA
May 22, 5:02 PM EDT	HAIL 0.75	Exton, PA
May 22, 5:05 PM EDT	HAIL 1.5	West Goshen, PA
May 22, 5:10 PM EDT	TSTM WND DMG	Cheyney, PA	TREE DOWN.
May 22, 5:14 PM EDT	HAIL 1.5	Glen Mills, PA

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

The watch it was issued in

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

Issued	Product	Office	Lasted
May 22, 12:39 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.5 hours before the alert went out and 193 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: 291 J/kg
Mixed-layer CIN: -102 J/kg
Mixed-layer LCL: 839 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 47 m²/s²
0-3 km storm-relative helicity: 91 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

082 
WUUS51 KPHI 222031
SVRPHI
PAC011-029-045-091-222115-
/O.NEW.KPHI.SV.W.0026.140522T2031Z-140522T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
431 PM EDT THU MAY 22 2014

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  SOUTHWESTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 515 PM EDT

* AT 428 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS. THESE SEVERE STORMS EXTENDED FROM
  AMITY GARDENS TO MOHNTON...MOVING SOUTHEAST AT 40 MPH. THESE
  STORMS ARE CAPABLE OF PRODUCING ONE INCH DIAMETER   HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH. 

* SEVERE THUNDERSTORMS WILL BE NEAR...
  ELVERSON AND PUGHTOWN AROUND 435 PM EDT...
  POTTSTOWN AROUND 440 PM EDT...
  GLENMOORE AND CHESTER SPRINGS AROUND 445 PM EDT...
  ROYERSFORD AND TRAPPE AROUND 450 PM EDT...
  PHOENIXVILLE AND PAOLI AROUND 455 PM EDT...
  VALLEY FORGE AND WEST CHESTER AROUND 500 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

VERY HEAVY RAIN WILL ALSO OCCUR WITH THIS LINE OF SEVERE
THUNDERSTORMS...WHICH COULD FLOOD LOW LYING AREAS QUICKLY AND COVER
ROADS WITH WATER. DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE
ROAD.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS LINE OF
SEVERE THUNDERSTORMS. WHEN THUNDER ROARS...MOVE INDOORS! REMEMBER...
IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY
LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
THURSDAY EVENING FOR NORTHERN NEW JERSEY AND EASTERN PENNSYLVANIA. A
SEVERE THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

&&

LAT...LON 4024 7604 4030 7581 4040 7571 4001 7526
      3988 7534 3983 7567 4012 7593 4014 7589
TIME...MOT...LOC 2030Z 320DEG 36KT 4031 7571 4022 7572
          4020 7595

$$

FORECASTER:  DRAG

2 follow-up statements

875 
WWUS51 KPHI 222103
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
503 PM EDT THU MAY 22 2014

PAC011-091-222113-
/O.CAN.KPHI.SV.W.0026.000000T0000Z-140522T2115Z/
BERKS PA-MONTGOMERY PA-
503 PM EDT THU MAY 22 2014

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN MONTGOMERY AND
SOUTHEASTERN BERKS COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE SEVERE THUNDERSTORM WARNING HAS 
WEAKENED...THEREFORE THE SEVERE THUNDERSTORM WARNING HAS BEEN 
CANCELLED.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
THURSDAY EVENING FOR NORTHERN NEW JERSEY AND EASTERN PENNSYLVANIA. A
SEVERE THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

LAT...LON 4002 7573 4012 7561 4007 7539 3988 7534
      3983 7567
TIME...MOT...LOC 2103Z 320DEG 36KT 4005 7548 3997 7544
          3995 7567

$$

PAC029-045-222115-
/O.CON.KPHI.SV.W.0026.000000T0000Z-140522T2115Z/
DELAWARE PA-CHESTER PA-
503 PM EDT THU MAY 22 2014

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR EASTERN CHESTER AND WESTERN DELAWARE COUNTIES...

AT 459 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS NEAR 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING 
FROM CHESTERBROOK TO PAOLI TO DOWNINGTOWN...MOVING SOUTHEAST AT 40 
MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
NEWTOWN SQUARE AND UPPER PROVIDENCE TOWNSHIP AROUND 510 PM EDT...
ELAM AND SWARTHMORE AROUND 515 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
THURSDAY EVENING FOR NORTHERN NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4002 7573 4012 7561 4007 7539 3988 7534
      3983 7567
TIME...MOT...LOC 2103Z 320DEG 36KT 4005 7548 3997 7544
          3995 7567

$$

FORECASTER:  DRAG

509 
WWUS51 KPHI 222112
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
512 PM EDT THU MAY 22 2014

PAC029-045-222121-
/O.EXP.KPHI.SV.W.0026.000000T0000Z-140522T2115Z/
DELAWARE PA-CHESTER PA-
512 PM EDT THU MAY 22 2014

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN CHESTER AND WESTERN
DELAWARE COUNTIES WILL EXPIRE AT 515 PM EDT...

THE SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.

THE THUNDERSTORMS HAVE WEAKENED. 

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
THURSDAY EVENING FOR NORTHERN NEW JERSEY AND EASTERN PENNSYLVANIA. A
SEVERE THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

LAT...LON 4002 7573 4012 7561 4006 7539 3988 7534
      3983 7567
TIME...MOT...LOC 2111Z 320DEG 36KT 3999 7541 3991 7537
          3989 7560

$$

FORECASTER:  DRAG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 22, 3:25 AM EDT	Special Weather Statement	PHI	Lehigh	65 min
May 22, 2:12 PM EDT	Special Weather Statement	PHI	Berks	63 min
May 22, 2:14 PM EDT	Severe Thunderstorm Warning	PHI	Berks	46 min
May 22, 2:29 PM EDT	Special Weather Statement	PHI	Carbon	46 min
May 22, 2:40 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Lehigh, Monroe, Northampton	50 min
May 22, 2:50 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	55 min
May 22, 3:09 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	66 min
May 22, 3:21 PM EDT	Special Weather Statement	PHI	Northampton	24 min
May 22, 3:27 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh, Northampton	33 min
May 22, 3:33 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery	57 min
May 22, 3:51 PM EDT	Severe Thunderstorm Warning	PHI	Berks	39 min
May 22, 3:56 PM EDT	Special Weather Statement	PHI	Bucks	34 min
May 22, 4:13 PM EDT	Severe Thunderstorm Warning	PHI	Delaware, Philadelphia	62 min
May 22, 4:22 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	38 min
May 22, 4:22 PM EDT	Severe Thunderstorm Warning	PHI	Delaware, Philadelphia	53 min
May 22, 5:23 PM EDT	Special Weather Statement	PHI	Delaware	37 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2014 Every severe thunderstorm warning in 2014

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.