Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 270, NWS Philadelphia/Mount Holly

November 15, 20085 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 15, 2008, 4:15 PM EST for 5 counties in Pennsylvania. It was in force for 60 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
Nov 15, 2008, 4:15 PM EST (21:15 UTC)
Expired
Nov 15, 2008, 5:15 PM EST
In force
60 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 112 km from the middle of the area, began a volume at 21:18 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
Nov 15, 4:40 PM ESTTSTM WND DMG3 E Emmaus, PATREE REPORTED DOWN IN UPPER SAUCON 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.

IssuedProductOfficeLasted
Nov 15, 12:22 PM ESTTornado WatchSPC7 hr
Nov 15, 2:56 PM ESTTornado WatchSPC6 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.3 hours before the alert went out and 228 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 2008-11-15Temperature 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 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 2008-11-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 246 square meters per square second.1939587897117Sfc1 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
604 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
246 m²/s²
0-3 km storm-relative helicity
314 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 152115 RRA
SVRPHI
PAC011-017-029-077-091-152215-
/O.NEW.KPHI.SV.W.0270.081115T2115Z-081115T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
415 PM EST SAT NOV 15 2008

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  NORTHEASTERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
  MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 515 PM EST

* AT 409 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS 
  IN EXCESS OF 60 MPH.  THIS LINE EXTENDED FROM NEAR ALLENTOWN TO    
  NEAR WEST CHESTER...AND MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  GERYVILLE AND ZIONSVILLE BY 420 PM...
  QUAKERTOWN BY 430 PM...
  PERKASIE BY 435 PM...
  DUBLIN BY 440 PM...
  BEDMINSTER...PIPERSVILLE...OTTSVILLE AND REVERE BY 445 PM...
  TINICUM BY 450 PM...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 700 PM SATURDAY EVENING FOR
DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW JERSEY AND
SOUTHEASTERN PENNSYLVANIA. A TORNADO WATCH ALSO REMAINS IN EFFECT
UNTIL 900 PM SATURDAY EVENING FOR NORTHWESTERN NEW JERSEY AND
NORTHEASTERN PENNSYLVANIA.

LAT...LON 4068 7587 4077 7565 4061 7547 4051 7536
      4058 7521 4041 7505 4005 7542 4008 7581
TIME...MOT...LOC 2114Z 262DEG 35KT 4040 7555

$$

NIERENBERG
1 follow-up statement
000 
WWUS51 KPHI 152137
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
437 PM EST SAT NOV 15 2008

PAC011-017-029-077-091-152215-
/O.CON.KPHI.SV.W.0270.000000T0000Z-081115T2215Z/
CHESTER PA-MONTGOMERY PA-BERKS PA-LEHIGH PA-BUCKS PA-
437 PM EST SAT NOV 15 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EST
FOR NORTHWESTERN BUCKS...SOUTHEASTERN LEHIGH...EXTREME EAST CENTRAL
BERKS...MONTGOMERY AND NORTHEASTERN CHESTER COUNTIES...

AT 432 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING 
WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED FROM ALLENTOWN TO
NEAR RED HILL...OR 15 MILES SOUTH OF ALLENTOWN...MOVING EAST AT 40 
MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  PERKASIE...SELLERSVILLE AND SILVERDALE BY 445 PM EST...
  DUBLIN BY 450 PM EST...
  BEDMINSTER AND OTTSVILLE BY 455 PM EST...
  PIPERSVILLE...TINICUM AND GARDENVILLE BY 500 PM EST...
  BYRAM BY 505 PM EST...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 700 PM EST SATURDAY EVENING
FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW JERSEY AND
SOUTHEASTERN PENNSYLVANIA. A TORNADO WATCH ALSO REMAINS IN EFFECT
UNTIL 900 PM EST SATURDAY EVENING FOR NORTHWESTERN NEW JERSEY AND
NORTHEASTERN PENNSYLVANIA.

LAT...LON 4057 7560 4061 7547 4051 7536 4058 7521
      4041 7505 4005 7542 4005 7544 4005 7545
      4005 7551 4007 7561
TIME...MOT...LOC 2137Z 262DEG 35KT 4038 7540

$$

TFG

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 15, 3:54 PM ESTSevere Thunderstorm WarningPHIBerks38 min
Nov 15, 4:33 PM ESTSevere Thunderstorm WarningPHILehigh, Northampton38 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.