Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 147, NWS Philadelphia/Mount Holly

July 27, 2014Bucks County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 27, 2014, 10:47 PM EDT for Bucks County, Montgomery County, Pennsylvania. It was in force for 43 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 27, 2014, 10:47 PM EDT (02:47 UTC)
Expired: Jul 27, 2014, 11:30 PM EDT
In force: 43 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Bucks County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 89 km from the middle of the area, began a volume at 02:50 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 27, 10:50 PM EDT	TSTM WND DMG	Lower Salford Twp, PA	A FEW TREES DOWN IN LOWER SALFORD TWP. TREE DOWN ALONG CRESSMAN ROAD AND SHADYNOOK ROAD. TREE DOWN ALONG OLD SKIPPACK ROAD. TREE DOWN ALONG MAIN STREET AND MAPLE AVE. TREE DOWN ALONG CLEMENS ROAD AND ASTOR DRIVE.
Jul 27, 10:57 PM EDT	TSTM WND DMG	Franconia Twp, PA	TREE DOWN IN FRANCONIA TOWNSHIP.

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
Jul 27, 6:52 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 2.8 hours before the alert went out and 221 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: 1013 J/kg
Mixed-layer CIN: -35 J/kg
Mixed-layer LCL: 1007 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 67 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 2.7

Open this sounding in Storm Lab

The text

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

400 
WUUS51 KPHI 280247
SVRPHI
PAC017-091-280330-
/O.NEW.KPHI.SV.W.0147.140728T0247Z-140728T0330Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1047 PM EDT SUN JUL 27 2014

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  CENTRAL MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 1130 PM EDT

* AT 1045 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM. THE STORM WAS NEAR SKIPPACK...MOVING NORTHEAST
  AT 25 MPH. THIS STORM IS CAPABLE OF PRODUCING QUARTER SIZE HAIL...
  AND DAMAGING WINDS IN EXCESS OF 60 MPH. 

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HATFIELD AND SOUDERTON AROUND 1100 PM EDT...
  FRICKS AND CHALFONT AROUND 1110 PM EDT...
  DOYLESTOWN AND DUBLIN AROUND 1120 PM EDT...
  ROBESONIA AND GARDENVILLE AROUND 1125 PM EDT...
  TINICUM AROUND 1130 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

DOPPLER RADAR HAS INDICATED SOME 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 ON THE LOWEST
FLOOR.

&&

LAT...LON 4027 7559 4053 7515 4022 7491 4010 7546
      4011 7548 4012 7546 4013 7547 4012 7548
TIME...MOT...LOC 0247Z 241DEG 23KT 4024 7541

$$

IOVINO

1 follow-up statement

411 
WWUS51 KPHI 280313
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1113 PM EDT SUN JUL 27 2014

PAC091-280322-
/O.CAN.KPHI.SV.W.0147.000000T0000Z-140728T0330Z/
MONTGOMERY PA-
1113 PM EDT SUN JUL 27 2014

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL MONTGOMERY COUNTY IS
CANCELLED...

THE STRONGEST WINDS ASSOCIATED WITH THE STORM HAVE MOVED INTO BUCKS 
COUNTY. AS A RESULT...THE WARNING HAS BEEN CANCELLED FOR MONTGOMERY 
COUNTY.

LAT...LON 4038 7541 4053 7515 4039 7504 4027 7523
TIME...MOT...LOC 0312Z 237DEG 23KT 4038 7526

$$

PAC017-280330-
/O.CON.KPHI.SV.W.0147.000000T0000Z-140728T0330Z/
BUCKS PA-
1113 PM EDT SUN JUL 27 2014

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 PM EDT
FOR CENTRAL BUCKS COUNTY...

AT 1110 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 PERKASIE...MOVING NORTHEAST AT 25 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  ROBESONIA BY 1120 PM EDT...
  BEDMINSTER...PIPERSVILLE...OTTSVILLE AND GARDENVILLE BY 1125 PM
  EDT...
  TINICUM AND REVERE BY 1130 PM EDT...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 4038 7541 4053 7515 4039 7504 4027 7523
TIME...MOT...LOC 0312Z 237DEG 23KT 4038 7526

$$

IOVINO

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 27, 8:28 PM EDT	Special Weather Statement	PHI	Berks	62 min
Jul 27, 8:42 PM EDT	Areal Flood Advisory	PHI	Chester, Montgomery	3 hr
Jul 27, 9:12 PM EDT	Special Weather Statement	PHI	Chester	63 min
Jul 27, 9:21 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester	54 min
Jul 27, 9:43 PM EDT	Flash Flood Warning	PHI	Berks, Chester, Montgomery	4 hr
Jul 27, 10:20 PM EDT	Special Weather Statement	PHI	Chester, Montgomery	55 min
Jul 27, 10:26 PM EDT	Areal Flood Advisory	PHI	Bucks, Lehigh, Northampton	3 hr
Jul 27, 10:33 PM EDT	Flash Flood Warning	PHI	Chester, Montgomery	4 hr
Jul 27, 10:44 PM EDT	Special Weather Statement	PHI	Chester, Delaware	61 min
Jul 27, 11:28 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	62 min
Jul 27, 11:32 PM EDT	Severe Thunderstorm Warning	PHI	Delaware, Philadelphia	58 min
Jul 28, 12:31 AM EDT	Flash Flood Warning	PHI	Delaware, Montgomery, Philadelphia	3 hr
Jul 28, 12:35 AM EDT	Special Weather Statement	PHI	Bucks, Chester, Delaware, Philadelphia	85 min
Jul 28, 2:58 AM EDT	River Flood Warning	PHI	Chester	8 hr

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; radar from the NEXRAD Level II archive.