Alert archive / Pennsylvania / Flash Flood Warnings in 2004

Flash Flood Warning 104, NWS Philadelphia/Mount Holly

September 28, 2004Cecil County, Kent County, Maryland; New Castle County, Delaware; Chester County, Delaware County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 28, 2004, 8:05 PM EDT for Cecil County, Kent County, Maryland; New Castle County, Delaware; Chester County, Delaware County, Philadelphia County, Pennsylvania. It was in force for 6 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: Sep 28, 2004, 8:05 PM EDT (00:05 UTC)
Expired: Sep 29, 2004, 2:00 AM EDT
In force: 6 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

Counties New Castle County, DE, Cecil County, MD, Kent County, MD, Chester County, PA, Delaware County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 101 km from the middle of the area, began a volume at 00:07 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.1 hours before the alert went out and 181 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 693 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: -65 m²/s²
0-3 km storm-relative helicity: 36 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 
WGUS51 KPHI 290010
FFWPHI
DEC003-MDC015-029-PAC029-045-101-290600-
/X.NEW.KPHI.FF.W.0023.040929T0005Z-040929T0600Z/
/0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
805 PM EDT TUE SEP 28 2004

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  CECIL COUNTY IN MARYLAND
  KENT COUNTY IN MARYLAND
  NEW CASTLE COUNTY IN DELAWARE
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK
  CHESTER COUNTY IN PENNSYLVANIA
  DELAWARE COUNTY IN PENNSYLVANIA
  PHILADELPHIA COUNTY IN PENNSYLVANIA
  
* UNTIL 200 AM EDT

* VERY HEAVY RAIN CONTINUES TO FALL OVER THE WARNING AREA.
  MANY SMALLER CREEKS ARE OUT OF THEIR BANKS AND WILL CONTINUE
  TO DO SO FOR THE REST OF THE EVENING. IN NEW CASTLE COUNTY
  THE CHRISTINA...WHITE AND RED CLAY CREEKS ARE FLOODING.
  IN PHILADELPHIA THE FRANKFORD AND WISSAHICKON CREEKS ARE 
  FLOODING. IN DELAWARE COUNTY THE DARBY AND HERMESPROTA CREEKS
  ARE FLOODING. DOPPLER RADAR STORM TOTAL ESTIMATES ARE APPROACHING
  10 INCHES ALONG THE PHILADELPHIA AND MONTGOMERY COUNTY BORDER 
  WITH WIDESPREAD STORM TOTALS OF 3 INCHES OR MORE ELSEWHERE IN
  THE WARNING AREA. THIS IS A DANGEROUS AND LIFE THREATENING
  SITUATION.  
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

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.

DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. ONLY A FEW INCHES OF
RAPIDLY FLOWING WATER CAN QUICKLY CARRY AWAY YOUR VEHICLE.

LAT...LON 3954 7600 3957 7602 4016 7578 4012 7548
      3998 7528 4001 7522 4005 7526 4009 7523
      4005 7512 4011 7502 3986 7523 3985 7536
      3964 7560 3955 7556 3947 7560 3944 7556
      3936 7564 3926 7614 3926 7614

$$

TFG

Nearby

Flash Flood Warnings in Pennsylvania, 2004 Flash Flood Warnings in Maryland, 2004 Flash Flood Warnings in Delaware, 2004 Every 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; radar from the NEXRAD Level II archive.