Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 149, NWS Philadelphia/Mount Holly

July 28, 2004Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 28, 2004, 7:10 PM EDT for Bucks County, Pennsylvania. It was in force for 50 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
Jul 28, 2004, 7:10 PM EDT (23:10 UTC)
Expired
Jul 28, 2004, 8:00 PM EDT
In force
50 min
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

County Bucks County, PA

The radar

The Philadelphia radar (KDIX), 73 km from the middle of the area, began a volume at 23:13 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 11.2 hours before the alert went out and 124 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, Phillips Aaf/Abe, MD at 12:00Z on 2004-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 112 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, Phillips Aaf/Abe, MD at 12:00Z on 2004-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 square meters per square second.19395878Sfc1 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
112 J/kg
Mixed-layer CIN
-44 J/kg
Mixed-layer LCL
752 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
43 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 282310
SVRPHI
PAC017-290000-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
709 PM EDT WED JUL 28 2004

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 800 PM EDT

* AT 704 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED NEAR CHALFONT...OR
  ABOUT 18 MILES NORTH OF PHILADELPHIA...AND MOVING EAST AT 20 MPH.
  RADAR INDICATED THIS STORM WAS GENERATING WINDS APPROACHING 60 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  IVYLAND BY 720 PM EDT...
  RICHBORO BY 730 PM EDT...
  NEWTOWN BY 740 PM EDT...
  WOODSIDE BY 750 PM EDT...

LAT...LON 4036 7535 4019 7508 4020 7481 4042 7506

$$
MPD

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 9:37 PM EDTSevere Thunderstorm WarningPHIBucks, Philadelphia38 min
Jul 27, 9:39 PM EDTSevere Thunderstorm WarningPHIBucks, Philadelphia36 min
Jul 27, 10:44 PM EDTFlash Flood WarningPHIBerks, Chester, Delaware, Montgomery, Philadelphia4 hr
Jul 28, 2:28 AM EDTFlash Flood WarningPHIBerks, Chester, Delaware, Montgomery, Philadelphia3 hr
Jul 28, 7:00 PM EDTFlash Flood WarningPHIMontgomery2 hr
Jul 28, 7:21 PM EDTFlash Flood WarningPHIBucks114 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2004Every severe thunderstorm warning in 2004

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.