Alert archive / Maryland / Flash Flood Warnings in 2004

Flash Flood Warning 12, NWS Philadelphia/Mount Holly

July 12, 2004Cecil County, Maryland; Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 12, 2004, 7:50 AM EDT for Cecil County, Maryland; Chester County, Pennsylvania. It was in force for 68 days. 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 12, 2004, 7:50 AM EDT (11:50 UTC)
Expired: Sep 18, 2004, 6:15 PM EDT
In force: 68 days
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

Counties Cecil County, MD, Chester County, PA

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 11.8 hours before the alert went out and 143 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: 1082 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 1273 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: -22 m²/s²
0-3 km storm-relative helicity: 37 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.9

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 121155
FFWPHI
PAC029-121345-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
750 AM EDT MON JUL 12 2004

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA

* UNTIL 945 AM EDT

* AT 748 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  THAT AT LEAST 2 INCHES OF RAIN HAS FALLEN OVER NORTH CENTRAL       
  CHESTER COUNTY DURING THE LAST HOUR OR SO. ADDITIONAL RAINFALL     
  AMOUNTS OF 1 INCH IS POSSIBLE IN THE WARNED AREA DURING THE NEXT   
  HOUR.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. 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.

LAT...LON 4014 7584 4005 7575 4015 7556 4023 7568

$$

KRUZDLO

1 follow-up statement

000 
WGUS51 KPHI 181916
FFWPHI
MDC015-182215-
/X.NEW.KPHI.FF.W.0012.040918T1911Z-040918T2215Z/
/0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
311 PM EDT SAT SEP 18 2004

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CECIL COUNTY IN NORTHEAST MARYLAND

* UNTIL 615 PM EDT

* AT 307 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  2 TO 3 INCHES OF RAIN HAD FALLEN ACROSS THE NORTHERN AND EASTERN   
  PORTIONS OF THE COUNTY. FLOODING IS POSSIBLE, BUT NOT LIMITED TO,  
  THE BIG ELK CREEK AS WELL AS THE OCTORARO CREEK. A NATIONAL        
  WEATHER SERVICE SPOTTER REPORTED MOVING WATER ON HOWARD ROAD.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. 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.

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 3958 7607 3946 7579 3971 7580 3971 7614

$$

KRUZDLO

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 12, 8:28 AM EDT	Flash Flood Warning	PHI	Cecil, Kent, Queen Anne's	78 days
Jul 12, 1:09 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	51 min
Jul 12, 1:17 PM EDT	Tornado Warning	PHI	Cecil	43 min
Jul 12, 2:52 PM EDT	Flash Flood Warning	PHI	Cecil	78 days
Jul 12, 4:49 PM EDT	Flash Flood Warning	PHI	Cecil	78 days
Jul 12, 5:26 PM EDT	Severe Thunderstorm Warning	PHI	Talbot	49 min
Jul 12, 5:45 PM EDT	Flash Flood Warning	PHI	Caroline, Cecil, Kent, Queen Anne's, Talbot	78 days
Jul 12, 6:51 PM EDT	Flash Flood Warning	PHI	Cecil	78 days
Jul 12, 7:26 AM EDT	Flash Flood Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	68 days
Jul 12, 9:31 AM EDT	Flash Flood Warning	PHI	Berks, Chester, Delaware	78 days
Jul 12, 12:10 PM EDT	Flash Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	78 days
Jul 12, 4:33 PM EDT	Flash Flood Warning	PHI	Carbon, Monroe	78 days
Jul 12, 4:50 PM EDT	Special Marine Warning	PHI		70 min
Jul 12, 7:32 PM EDT	Flash Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	78 days

Nearby

Flash Flood Warnings in Maryland, 2004 Flash Flood Warnings in Pennsylvania, 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.