Alert archive / Pennsylvania / Flash Flood Warnings in 2004
Flash Flood Warning 75, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 12, 2004, 8:50 PM EDT for Chester County, Pennsylvania. It was in force for 3 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 12, 2004, 8:50 PM EDT (00:50 UTC)
- Expired
- Aug 12, 2004, 11:45 PM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Counties, with a storm outline in the text
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 00:53 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, 0.8 hours before the alert went out and 176 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.
- Mixed-layer CAPE
- 134 J/kg
- Mixed-layer CIN
- -20 J/kg
- Mixed-layer LCL
- 640 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 128 m²/s²
- 0-3 km storm-relative helicity
- 180 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
000 WGUS51 KPHI 130058 FFWPHI PAC029-130345- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 850 PM EDT THU AUG 12 2004 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * FLASH FLOOD WARNING FOR... CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA * UNTIL 1145 PM EDT * AT 850 PM EDT...RADAR ESTIMATED RAINFALL AMOUNTS HAVE EXCEEDED 2.5 INCHES IN PORTIONS OF CENTRAL CHESTER COUNTY. ANOTHER 1 TO POSSIBLY 2 INCHES OF RAINFALL IS POSSIBLE DURING THE NEXT SEVERAL HOURS. FLOODING IS EXPECTED, BUT NOT LIMITED TO, LOCALES NEAR THE EAST BRANCH OF THE WHITE CLAY CREEK AND EAST BRANCH OF THE RED CLAY CREEK. 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 3978 7598 3990 7563 4012 7558 4012 7587 $$ KRUZDLO
1 follow-up statement
000 WGUS71 KPHI 130345 FFSPHI PAC029-130445- FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1144 PM EDT THU AUG 12 2004 ...THE FLASH FLOOD WARNING FOR CHESTER COUNTY IS BEING ALLOWED TO EXPIRE... WITH THE HEAVY SHOWERS AND THUNDERSTORMS COMING TO AN END, THE FLASH FLOOD WARNING FOR CHESTER COUNTY WILL BE ALLOWED TO EXPIRE. ALTHOUGH THE WARNING IS EXPIRING, COUNTY OFFICIALS STILL REPORT ISOLATED ROAD CLOSURES IN CALN TOWNSHIP, NEW GARDEN TOWNSHIP, AND BIRMINGHAM TOWNSHIP. DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. STAY TUNED TO NOAA WEATHER RADIO OR OTHER MEDIA FOR THE LATEST SEVERE WEATHER INFORMATION. $$ KRUZDLO
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 12, 10:42 PM EDT | Flash Flood Warning | PHI | Berks | 4 hr |
| Aug 12, 10:59 PM EDT | Flash Flood Warning | PHI | Monroe | 4 hr |
| Aug 13, 2:41 AM EDT | Flash Flood Warning | PHI | Berks | 3 hr |
| Aug 13, 2:49 AM EDT | Flash Flood Warning | PHI | Monroe | 3 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; radar from the NEXRAD Level II archive.