Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 91, NWS Philadelphia/Mount Holly

July 9, 20154 counties in Pennsylvania; Hunterdon County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 9, 2015, 7:12 PM EDT for 4 counties in Pennsylvania; Hunterdon County, Warren County, New Jersey. It was in force for 48 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
Jul 9, 2015, 7:12 PM EDT (23:12 UTC)
Expired
Jul 9, 2015, 8:00 PM EDT
In force
48 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Hunterdon County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 129 km from the middle of the area, began a volume at 23:14 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

TimeReportWhereRemark
Jul 9, 7:48 PM EDTTSTM WND DMGCenter Valley, PADAMAGE TO THE GYM ROOF AND SCOREBOARDS AT DESALES UNIVERSITY

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.

IssuedProductOfficeLasted
Jul 9, 4:57 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 11.2 hours before the alert went out and 225 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-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2015-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2015-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
757 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
129 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.

265 
WUUS51 KPHI 092312
SVRPHI
NJC019-041-PAC011-017-077-095-100000-
/O.NEW.KPHI.SV.W.0091.150709T2312Z-150710T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
712 PM EDT THU JUL 9 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL HUNTERDON COUNTY IN NORTHWESTERN NEW JERSEY...
  SOUTHWESTERN WARREN COUNTY IN NORTHWESTERN NEW JERSEY...
  NORTHWESTERN BUCKS COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  NORTHEASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...

* UNTIL 800 PM EDT

* AT 711 PM EDT...DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS
  CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS
  WERE LOCATED OVER NEW TRIPOLI...OR 12 MILES SOUTH OF LEHIGHTON...AND
  MOVING EAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
  ALLENTOWN...EASTON...BETHLEHEM...FORKS...EMMAUS...NORTHAMPTON...
  WILSON...WASHINGTON...HELLERTOWN...NAZARETH...BANGOR...KUTZTOWN...
  SLATINGTON...FLEETWOOD...HIGH BRIDGE...PEN ARGYL...WIND GAP...
  CLINTON...BATH AND BELVIDERE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DEADLY LIGHTNING AND 
VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON 
THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS 
QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4070 7583 4078 7567 4078 7562 4081 7554
      4083 7538 4085 7533 4092 7495 4056 7487
      4039 7589 4067 7593
TIME...MOT...LOC 2311Z 259DEG 49KT 4065 7578 

$$

GORSE/FRANCK
1 follow-up statement
495 
WWUS51 KPHI 092354
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
754 PM EDT THU JUL 9 2015

PAC011-100003-
/O.CAN.KPHI.SV.W.0091.000000T0000Z-150710T0000Z/
BERKS PA-
754 PM EDT THU JUL 9 2015

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BERKS COUNTY IS
CANCELLED...
    
THE SEVERE THUNDERSTORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF 
THE WARNED AREA. THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 4045 7550 4079 7557 4092 7495 4056 7487
TIME...MOT...LOC 2353Z 256DEG 39KT 4069 7514 

$$

NJC019-041-PAC017-077-095-100000-
/O.CON.KPHI.SV.W.0091.000000T0000Z-150710T0000Z/
HUNTERDON NJ-WARREN NJ-BUCKS PA-NORTHAMPTON PA-LEHIGH PA-
754 PM EDT THU JUL 9 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR CENTRAL HUNTERDON...SOUTHWESTERN WARREN...NORTHWESTERN BUCKS...
NORTHAMPTON AND EASTERN LEHIGH COUNTIES...

AT 753 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE
OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS
LOCATED OVER ALPHA...OR NEAR EASTON...MOVING EAST AT 45 MPH.

LOCATIONS IMPACTED INCLUDE...
ALLENTOWN...EASTON...BETHLEHEM...FORKS...EMMAUS...NORTHAMPTON...
WILSON...WASHINGTON...HELLERTOWN...NAZARETH...BANGOR...HIGH BRIDGE...
PEN ARGYL...WIND GAP...CLINTON...BATH...BELVIDERE...HARMONY...OXFORD
AND ALPHA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DEADLY LIGHTNING AND 
VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE 
LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS 
QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4045 7550 4079 7557 4092 7495 4056 7487
TIME...MOT...LOC 2353Z 256DEG 39KT 4069 7514 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 6:15 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery45 min
Jul 9, 6:35 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh40 min
Jul 9, 6:46 PM EDTAreal Flood AdvisoryPHICarbon, Lehigh, Monroe, Northampton4 hr
Jul 9, 6:50 PM EDTSevere Thunderstorm WarningPHIChester40 min
Jul 9, 6:57 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery48 min
Jul 9, 7:21 PM EDTAreal Flood AdvisoryPHIBerks, Lehigh4 hr
Jul 9, 7:29 PM EDTSevere Thunderstorm WarningPHIChester, Delaware46 min
Jul 9, 7:39 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia66 min
Jul 9, 7:55 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Philadelphia40 min
Jul 9, 7:56 PM EDTAreal Flood AdvisoryPHIBucks, Delaware, Montgomery, Philadelphia4 hr
Jul 9, 7:44 PM EDTSpecial Marine WarningPHI31 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015Severe Thunderstorm Warnings in New Jersey, 2015Every severe thunderstorm warning in 2015

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.