Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 37, NWS Philadelphia/Mount Holly

May 31, 2008Bucks County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 31, 2008, 10:09 PM EDT for Bucks County, Montgomery County, Pennsylvania. It was in force for 66 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 31, 2008, 10:09 PM EDT (02:09 UTC)
Expired
May 31, 2008, 11:15 PM EDT
In force
66 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Bucks County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 69 km from the middle of the area, began a volume at 02:08 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 2.2 hours before the alert went out and 201 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 00:00Z on 2008-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 88 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2008-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 215 square meters per square second.1939587897Sfc1 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
88 J/kg
Mixed-layer CIN
-175 J/kg
Mixed-layer LCL
724 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
214 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.

000 
WUUS51 KPHI 010209
SVRPHI
PAC017-091-010315-
/O.NEW.KPHI.SV.W.0037.080601T0209Z-080601T0315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1009 PM EDT SAT MAY 31 2008

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 1115 PM EDT

* AT 1004 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED NEAR PERKASIE...OR
  ABOUT 19 MILES SOUTHEAST OF ALLENTOWN...AND MOVING SOUTHEAST AT 40
  MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  CHALFONT AND 7 MILES SOUTHWEST OF GARDENVILLE BY 1015 PM...
  DOYLESTOWN BY 1020 PM...
  RICHBORO AND IVYLAND BY 1030 PM...
  FEASTERVILLE AND NEWTOWN BY 1035 PM...
  LANGHORNE AND WOODSIDE BY 1040 PM...

LAT...LON 4013 7502 4038 7556 4047 7517 4019 7476
TIME...MOT...LOC 0209Z 302DEG 35KT 4033 7526

$$

RNS
3 follow-up statements
000 
WWUS51 KPHI 010214
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1015 PM EDT SAT MAY 31 2008

PAC017-091-010315-
/O.CON.KPHI.SV.W.0037.000000T0000Z-080601T0315Z/
MONTGOMERY PA-BUCKS PA-
1015 PM EDT SAT MAY 31 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR BUCKS AND NORTHEASTERN MONTGOMERY COUNTIES...

AT 1013 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR FRICKS...OR 21 MILES NORTH OF PHILADELPHIA...MOVING
SOUTHEAST AT 40 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  DOYLESTOWN BY 1020 PM EDT...
  RICHBORO...IVYLAND...WARMINSTER HEIGHTS AND HATBORO BY 1030 PM
  EDT...
  CHURCHVILLE...VILLAGE SHIRES...FEASTERVILLE AND NEWTOWN BY 1035 PM
  EDT...
  PENNDEL BY 1040 PM EDT...

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 NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

LAT...LON 4013 7502 4038 7556 4047 7517 4019 7476
TIME...MOT...LOC 0215Z 302DEG 35KT 4030 7520

$$
RNS
000 
WWUS51 KPHI 010245
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1045 PM EDT SAT MAY 31 2008

PAC017-091-010315-
/O.CON.KPHI.SV.W.0037.000000T0000Z-080601T0315Z/
MONTGOMERY PA-BUCKS PA-
1045 PM EDT SAT MAY 31 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR BUCKS AND NORTHEASTERN MONTGOMERY COUNTIES...

AT 1040 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING PENNY SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. 
THIS STORM WAS LOCATED NEAR SILVERDALE...OR 22 MILES SOUTH OF
BETHLEHEM...MOVING SOUTHEAST AT 38 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  NEW BRITAIN AND DOYLESTOWN BY 1050 PM EDT...
  IVYLAND...WARMINSTER HEIGHTS AND HATBORO BY 1100 PM EDT...
  CHURCHVILLE...RICHBORO AND NEWTOWN GRANT BY 1105 PM EDT...
  VILLAGE SHIRES AND NEWTOWN BY 1110 PM EDT...

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 NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

LAT...LON 4013 7502 4038 7556 4047 7517 4019 7476
TIME...MOT...LOC 0245Z 299DEG 33KT 4030 7521

$$

RNS
000 
WWUS51 KPHI 010258
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1058 PM EDT SAT MAY 31 2008

PAC017-091-010315-
/O.CON.KPHI.SV.W.0037.000000T0000Z-080601T0315Z/
MONTGOMERY PA-BUCKS PA-
1058 PM EDT SAT MAY 31 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR CENTRAL BUCKS AND EAST CENTRAL MONTGOMERY COUNTIES...

AT 1054 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING PENNY SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. 
THIS STORM WAS LOCATED NEAR BRITTANY FARMS-HIGHLANDS...OR 19 MILES
NORTH OF PHILADELPHIA...MOVING SOUTHEAST AT 34 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  IVYLAND...WARMINSTER HEIGHTS AND HATBORO BY 1105 PM EDT...
  RICHBORO AND NEWTOWN GRANT BY 1110 PM EDT...
  CHURCHVILLE...VILLAGE SHIRES...FEASTERVILLE AND LANGHORNE BY 1115
  PM EDT...

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 NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

LAT...LON 4021 7480 4015 7493 4013 7502 4025 7528
      4033 7507
TIME...MOT...LOC 0258Z 304DEG 29KT 4026 7514

$$

RNS

The office that day

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

IssuedProductOfficeCountiesLasted
May 31, 10:25 PM EDTAreal Flood WarningPHIBucks73 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2008Every severe thunderstorm warning in 2008

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.