Alert archive / New Jersey / Areal Flood Warnings in 2012

Areal Flood Warning 21, NWS Philadelphia/Mount Holly

September 4, 2012Bucks County, Montgomery County, Philadelphia County, Pennsylvania; 8 counties in New Jersey

NWS Philadelphia/Mount Holly issued this areal flood warning at Sep 4, 2012, 12:08 PM EDT for Bucks County, Montgomery County, Philadelphia County, Pennsylvania; 8 counties in New Jersey. 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 4, 2012, 12:08 PM EDT (16:08 UTC)
Expired: Sep 4, 2012, 4:00 PM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Somerset County, NJ, Bucks County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 28 km from the middle of the area, began a volume at 16:09 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, 4.1 hours before the alert went out and 142 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: 869 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 600 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

Open this sounding in Storm Lab

The text

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

516 
WGUS41 KPHI 041608
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1208 PM EDT TUE SEP 4 2012

NJC001-005-007-021-023-025-029-035-PAC017-091-101-042000-
/O.NEW.KPHI.FA.W.0021.120904T1608Z-120904T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CAMDEN NJ-MERCER NJ-SOMERSET NJ-BUCKS PA-MONTGOMERY PA-
PHILADELPHIA PA-MIDDLESEX NJ-BURLINGTON NJ-MONMOUTH NJ-ATLANTIC NJ-
OCEAN NJ-
1208 PM EDT TUE SEP 4 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLOOD WARNING FOR URBAN AREAS AND SMALL STREAMS IN...
  CAMDEN COUNTY IN SOUTHERN NEW JERSEY...
  MERCER COUNTY IN CENTRAL NEW JERSEY...
  SOUTH CENTRAL SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  SOUTHEASTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHEASTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  NORTHEASTERN PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHWESTERN MIDDLESEX COUNTY IN NORTHERN NEW JERSEY...
  BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...
  SOUTHWESTERN MONMOUTH COUNTY IN CENTRAL NEW JERSEY...
  ATLANTIC COUNTY IN SOUTHERN NEW JERSEY...
  OCEAN COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 400 PM EDT

* AT 1201 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED  
SHOWERS AND THUNDERSTORMS PRODUCING HEAVY RAINFALL EXTENDING 
SOUTHEAST FROM PHILADELPHIA AND BUCKS COUNTIES IN PENNSYLVANIA TO 
ATLANTIC COUNTY IN NEW JERSEY. THE PRECIPITATION WAS MOVING TO THE 
NORTHEAST AROUND 15 MPH. THE SHOWERS ARE EXPECTED TO PRODUCE 
RAINFALL TOTALS OF AN INCH OR TWO IN A SHORT AMOUNT OF TIME. 
LOCALIZED RAINFALL AMOUNTS OF TWO TO THREE INCHES ARE POSSIBLE. 

THE HEAVY RAIN WILL CAUSE FLOODING ON AREA ROADWAYS, AS WELL AS 
FLOODING IN AREAS OF POOR DRAINAGE AND ALONG SMALL STREAMS AND 
CREEKS. 

THE PENNYPACK CREEK IN PHILADELPHIA COUNTY HAS ALREADY EXCEEDED 
FLOOD STAGE AND WATER IS OUT OF IT'S BANKS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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. MOVE TO HIGHER GROUND.

DRIVING INTO FLOOD WATERS COULD PUT YOUR LIFE AT RISK AND COST YOU
THOUSANDS OF DOLLARS IN VEHICLE REPAIRS. FLOOD WATERS MAY BE DEEPER
THAN YOU THINK. TURN AROUND AND FIND AN ALTERNATE ROUTE.

&&

LAT...LON 3957 7422 3950 7435 3953 7435 3953 7440
      3948 7438 3931 7471 3960 7489 3966 7491
      3970 7495 4016 7524 4048 7455 3980 7416
      3975 7418 3972 7415 3977 7414 3972 7411

$$

KRUZDLO

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 4, 12:13 AM EDT	Areal Flood Advisory	PHI	Chester	111 min
Sep 4, 3:41 AM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery, Philadelphia	2 hr
Sep 4, 4:00 AM EDT	Flash Flood Warning	PHI	Bucks, Montgomery, Philadelphia	84 min
Sep 4, 12:15 PM EDT	Areal Flood Warning	PHI	Berks, Chester, Delaware, Montgomery, Philadelphia	106 min
Sep 4, 1:47 PM EDT	Flash Flood Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	3 hr
Sep 4, 2:22 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Chester, Delaware, Lehigh, Montgomery and 1 more	4 hr
Sep 4, 2:59 PM EDT	Special Weather Statement	PHI	Lehigh, Northampton	61 min
Sep 4, 3:11 PM EDT	River Flood Warning	PHI	Delaware	50 min
Sep 4, 3:32 PM EDT	Areal Flood Advisory	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	4 hr
Sep 4, 3:40 PM EDT	Areal Flood Advisory	PHI	Monroe, Northampton	4 hr
Sep 4, 4:37 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	3 hr
Sep 4, 5:22 PM EDT	Special Weather Statement	PHI	Philadelphia	53 min
Sep 4, 6:10 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Philadelphia	65 min
Sep 4, 6:34 PM EDT	Special Weather Statement	PHI	Lehigh	56 min
Sep 4, 7:01 PM EDT	Areal Flood Warning	PHI	Philadelphia	55 min
Sep 4, 7:06 PM EDT	Areal Flood Advisory	PHI	Bucks, Carbon, Lehigh, Monroe, Northampton	114 min
Sep 4, 7:33 PM EDT	Flash Flood Warning	PHI	Carbon, Monroe, Northampton	6 hr
Sep 3, 9:28 PM EDT	Areal Flood Advisory	PHI	Burlington, Ocean	3 hr
Sep 4, 12:05 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Monmouth, Ocean	4 hr
Sep 4, 1:25 AM EDT	Areal Flood Advisory	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean, Somerset	4 hr
Sep 4, 1:34 AM EDT	Flash Flood Warning	PHI	Burlington, Ocean	6 hr
Sep 4, 1:55 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Gloucester	4 hr
Sep 4, 3:48 AM EDT	Areal Flood Advisory	PHI	Ocean	3 hr
Sep 4, 4:44 AM EDT	Areal Flood Advisory	PHI	Ocean	2 hr
Sep 4, 4:55 AM EDT	Small Craft Advisory	PHI		47 hr
Sep 4, 6:47 AM EDT	Areal Flood Warning	PHI	Burlington, Ocean	3 hr
Sep 4, 12:39 PM EDT	Rip Current Statement	PHI	Atlantic, Cape May, Monmouth, Ocean	56 hr
Sep 4, 1:13 PM EDT	Severe Thunderstorm Warning	PHI	Monmouth, Ocean	62 min
Sep 4, 1:36 PM EDT	Flash Flood Warning	PHI	Monmouth, Ocean	4 hr
Sep 4, 1:58 PM EDT	Special Weather Statement	PHI	Burlington	62 min
Sep 4, 2:11 PM EDT	Special Weather Statement	PHI	Monmouth	34 min
Sep 4, 3:13 PM EDT	Tornado Warning	PHI	Burlington, Ocean	32 min
Sep 4, 4:13 PM EDT	Areal Flood Advisory	PHI	Burlington, Monmouth, Ocean	54 min
Sep 4, 6:02 PM EDT	Areal Flood Warning	PHI	Burlington	16 hr
Sep 4, 6:30 PM EDT	Tornado Warning	PHI	Burlington, Camden	30 min
Sep 4, 7:15 PM EDT	Special Weather Statement	PHI	Mercer	60 min

Nearby

Areal Flood Warnings in New Jersey, 2012 Areal Flood Warnings in Pennsylvania, 2012 Every areal flood warning in 2012

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.