Alert archive / Pennsylvania / Flash Flood Warnings in 2004

Flash Flood Warning 63, NWS Philadelphia/Mount Holly

August 1, 2004Delaware County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 1, 2004, 12:52 PM EDT for Delaware County, Philadelphia County, Pennsylvania. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 1, 2004, 12:52 PM EDT (16:52 UTC)
Expired
Aug 1, 2004, 5:00 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

Counties Delaware County, PA, Philadelphia County, PA

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 4.9 hours before the alert went out and 211 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, Washington/Dulle, VA at 12:00Z on 2004-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1100 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, Washington/Dulle, VA at 12:00Z on 2004-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 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
1100 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
506 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.0

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 011658
FFWPHI
PAC045-101-012100-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1252 PM EDT SUN AUG 1 2004

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA

* UNTIL 500 PM EDT

* AT 1246 PM EDT...ONGOING FLOODING WAS REPORTED ALONG THE DARBY
  AND CRUM CREEKS IN DELAWARE COUNTY AND THE WISSAHICKON CREEK
  IN PHILADELPHIA. ALL THE CREEKS HAVE CRESTED...BUT THE DOPPLER
  RADAR STORM TOTAL ESTIMATES OF 3 TO 6 INCHES HAVE TO RUN THROUGH
  THE STREAMS. FOLLOW THE DIRECTION OF EMERGENCY MANAGEMENT 
  PERSONNEL IN YOUR AREA.
 

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY OR HAVE BEEN BARRICADED.  THE WATER DEPTH MAY BE TOO GREAT
TO ALLOW YOUR CAR TO CROSS SAFELY. VEHICLES CAUGHT IN RISING WATER
SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHER GROUND.

FLOODING IS OCCURRING. MOST FLOOD RELATED DEATHS OCCUR
IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED BRIDGES...
DIPS...OR LOW WATER CROSSINGS. NEVER TRY TO CROSS A FLOWING STREAM...
EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER
GROUND.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

LAT...LON 3993 7548 3985 7540 4002 7503 4006 7518

$$

TFG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 7:12 AM EDTFlash Flood WarningPHIMontgomery2 hr
Aug 1, 7:30 AM EDTFlash Flood WarningPHIPhiladelphia2 hr
Aug 1, 7:43 AM EDTFlash Flood WarningPHIBucks2 hr
Aug 1, 7:50 AM EDTFlash Flood WarningPHIChester, Delaware115 min
Aug 1, 8:01 AM EDTFlash Flood WarningPHIMontgomery89 min
Aug 1, 9:08 AM EDTFlash Flood WarningPHIChester, Delaware, Montgomery, Philadelphia2 hr
Aug 1, 10:59 AM EDTFlash Flood WarningPHIDelaware, Montgomery, Philadelphia2 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2004Every flash flood 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.