Alert archive / Pennsylvania / Flash Flood Warnings in 2004

Flash Flood Warning 102, NWS Philadelphia/Mount Holly

September 28, 20045 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 28, 2004, 7:11 PM EDT for 5 counties in 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, 7:11 PM EDT (23:11 UTC)
Expired: Sep 29, 2004, 1:15 AM EDT
In force: 6 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

Counties Berks County, PA, Bucks County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 91 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 141 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: 95 J/kg
Mixed-layer CIN: -78 J/kg
Mixed-layer LCL: 631 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 109 m²/s²
0-3 km storm-relative helicity: 172 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 282314
FFWPHI
PAC011-017-077-091-095-290515-
/X.NEW.KPHI.FF.W.0021.040928T2311Z-040929T0515Z/
/0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED
THE 

* FLASH FLOOD WARNING FOR...
  BERKS COUNTY 
  LEHIGH COUNTY 
  THIS INCLUDES THE CITY OF ALLENTOWN
  NORTHAMPTON COUNTY 
  THIS INCLUDES THE CITY OF BETHLEHEM
  BUCKS COUNTY 
  MONTGOMERY COUNTY 

* UNTIL 115 AM EDT

* AT 705 PM EDT TORRENTIAL DOWNPOURS CONTINUE ACROSS MUCH OF
  THE WARNING AREA. DOPPLER RADAR STORM TOTAL ESTIMATES HAVE 
  AVERAGED BETWEEN 2.5 AND 6 INCHES ACROSS THE WARNING AREA
  WITH THE HIGHEST AMOUNTS IN LOWER BUCKS AND MONTGOMERY 
  COUNTIES. NEVER EVER DRIVE AROUND BARRICADES...THIS IS
  A LIFE THREATENING SITUATION. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  SCHNECKSVILLE...OLD ORCHARD...NORTHAMPTON...NAZARETH...
  LENHARTSVILLE...KUTZTOWN...HELLERTOWN...EMMAUS...EASTON...
  BELFAST...BATH AND ANCIENT OAKS.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

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. IT IS DIFFICULT AT NIGHT TO SEE THE DEPTH 
OF WATER ON ROADWAYS. TURN AROUND, DONT DROWN.



LAT...LON 4076 7519 4069 7522 4067 7519 4065 7522
      4057 7520 4055 7508 4043 7507 4039 7497
      4035 7496 4030 7489 4022 7484 4009 7534
      4059 7600 4084 7525

$$

TFG

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 28, 12:48 PM EDT	Flash Flood Warning	PHI	Monroe, Northampton	3 hr
Sep 28, 3:55 PM EDT	Flash Flood Warning	PHI	Chester, Delaware	3 hr
Sep 28, 4:16 PM EDT	Flash Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	3 hr
Sep 28, 4:41 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	79 min
Sep 28, 4:55 PM EDT	Flash Flood Warning	PHI	Carbon, Monroe	4 hr
Sep 28, 5:11 PM EDT	Flash Flood Warning	PHI	Philadelphia	3 hr
Sep 28, 6:05 PM EDT	Special Marine Warning	PHI		115 min
Sep 28, 6:47 PM EDT	Flash Flood Warning	PHI	Chester, Delaware	3 hr

Nearby

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; radar from the NEXRAD Level II archive.