Alert archive / Pennsylvania / Flash Flood Warnings in 2004

Flash Flood Warning 85, NWS Philadelphia/Mount Holly

September 18, 2004Hunterdon County, New Jersey; Bucks County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 18, 2004, 7:07 AM EDT for Hunterdon County, New Jersey; Bucks County, Montgomery 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: Sep 18, 2004, 7:07 AM EDT (11:07 UTC)
Expired: Sep 18, 2004, 11:00 AM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

Counties Hunterdon County, NJ, Bucks County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 83 km from the middle of the area, began a volume at 11:06 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

Brookhaven, NY (KOKX), launched 00:00Z, 11.1 hours before the alert went out and 208 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 678 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 130 m²/s²
0-3 km storm-relative helicity: 180 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 181109
FFWPHI
NJC019-PAC017-091-181500-
/X.NEW.KPHI.FF.W.0005.040918T1107Z-040918T1500Z/
/0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN HUNTERDON COUNTY IN NORTHWEST NEW JERSEY
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA
  NORTHWESTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA

* UNTIL 1100 AM EDT

* AT 702 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
FLASH FLOODING FROM PERSISTENT HEAVY RAIN AND THUNDERSTORMS OVER THE 
WARNED AREA. RADAR HAS ESTIMATED 3 TO 4 INCHES WITH LOCAL 5 INCH 
AMOUNTS WITHIN THE PAST 6 TO 8 HOURS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  QUAKERTOWN...MILFORD...HIGH BRIDGE...FRENCHTOWN AND FLEMINGTON.

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. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

LAT...LON 4012 7541 4053 7480 4072 7489 4027 7566

$$

JRP

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 18, 6:09 AM EDT	Flash Flood Warning	PHI	Warren	4 hr
Sep 18, 6:22 AM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	38 min
Sep 18, 6:46 AM EDT	Flash Flood Warning	PHI	Sussex	3 hr
Sep 18, 7:04 AM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	86 min
Sep 18, 7:37 AM EDT	Flash Flood Warning	PHI	Morris	4 hr
Sep 18, 9:48 AM EDT	Flash Flood Warning	PHI	Sussex, Warren	4 hr
Sep 18, 3:29 AM EDT	Severe Thunderstorm Warning	PHI	Chester	31 min
Sep 18, 10:31 AM EDT	Flash Flood Warning	PHI	Chester, Delaware	3 hr
Sep 18, 10:57 AM EDT	Flash Flood Warning	PHI	Bucks, Montgomery	3 hr
Sep 18, 1:45 PM EDT	Flash Flood Warning	PHI	Bucks, Chester, Delaware, Montgomery	2 hr
Sep 18, 2:00 PM EDT	Flash Flood Warning	PHI	Carbon, Lehigh, Monroe, Northampton	3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2004 Flash Flood Warnings in New Jersey, 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.