Alert archive / New Jersey / Flash Flood Watches in 2011

Flash Flood Watch 10, NWS Philadelphia/Mount Holly

November 22, 20117 counties in New Jersey; New Castle County, Delaware; 7 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood watch at Nov 22, 2011, 2:48 PM EST for 7 counties in New Jersey; New Castle County, Delaware; 7 counties in Pennsylvania. It took effect at Nov 22, 2011, 10:00 PM EST. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Nov 22, 2011, 2:48 PM EST (19:48 UTC)
In effect from
Nov 22, 2011, 10:00 PM EST
Expired
Nov 23, 2011, 6:34 AM EST
In force
9 hr
Issued by
NWS Philadelphia/Mount Holly
Flood severity
None

Counties New Castle County, DE, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Berks County, PA, Carbon County, PA, Delaware County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 89 km from the middle of the area, began a volume at 19:50 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, 7.8 hours before the alert went out and 144 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-pSkew-T log-p diagram, Phillips Aaf/Abe, MD at 12:00Z on 2011-11-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2011-11-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 153 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
446 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
153 m²/s²
0-3 km storm-relative helicity
197 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.

170 
WGUS61 KPHI 221948
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
248 PM EST TUE NOV 22 2011

NJZ001-007>010-012-015-PAZ060>062-067>071-231100-
/O.NEW.KPHI.FF.A.0010.111123T0300Z-111123T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-BERKS-
LEHIGH-NORTHAMPTON-CHESTER-MONTGOMERY-BUCKS-DELAWARE-PHILADELPHIA-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...READING...
ALLENTOWN...BETHLEHEM...EASTON...WEST CHESTER...NORRISTOWN...
DOYLESTOWN...MEDIA...PHILADELPHIA
248 PM EST TUE NOV 22 2011

...FLASH FLOOD WATCH IN EFFECT FROM 10 PM EST THIS EVENING
THROUGH WEDNESDAY AFTERNOON...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A

* FLASH FLOOD WATCH FOR PORTIONS OF NEW JERSEY AND 
  PENNSYLVANIA...INCLUDING THE FOLLOWING AREAS...IN NEW JERSEY...
   HUNTERDON...MERCER...MIDDLESEX...MORRIS...SOMERSET...SUSSEX 
  AND WARREN. IN PENNSYLVANIA...BERKS...BUCKS...CHESTER... 
  DELAWARE...LEHIGH...MONTGOMERY...NORTHAMPTON AND PHILADELPHIA. 

* FROM 10 PM EST THIS EVENING THROUGH WEDNESDAY AFTERNOON

* A COMPLEX LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY
  INTO OUR REGION LATER TONIGHT AND PRODUCE A COPIOUS AMOUNT OF
  RAIN OVER A RATHER SHORT TIME PERIOD. RAIN WILL BE HEAVY AT
  TIMES TONIGHT AND EARLY WEDNESDAY MORNING AS THE SYSTEM WRAPS UP
  AND MOVES TO OUR NORTHEAST. WIDESPREAD RAINFALL AMOUNTS OF ONE
  TO THREE INCHES ARE POSSIBLE IN THE WATCH AREA THROUGH WEDNESDAY
  AFTERNOON WITH EVEN HIGHER AMOUNTS FROM ISOLATED THUNDERSTORMS.

* IMPACTS FROM FLOODING WILL INCLUDE...SMALL STREAM, POOR
  DRAINAGE, URBAN AREA, BASEMENT, AND ROADWAY FLOODING. THE LARGER
  RIVERS SHOULD BE ABLE TO TAKE THE EXCESSIVE RAINFALL AMOUNTS BUT
  THEY MAY RUN HIGH AND A FEW MAY POSSIBLY APPROACH FLOOD STAGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION.

YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION
SHOULD FLASH FLOOD WARNINGS BE ISSUED.

&&

$$

HEAVENER
3 follow-up statements
136 
WGUS61 KPHI 230228
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
928 PM EST TUE NOV 22 2011

DEZ001-231100-
/O.EXA.KPHI.FF.A.0010.111123T0300Z-111123T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE-
INCLUDING THE CITY OF...WILMINGTON
928 PM EST TUE NOV 22 2011

...FLASH FLOOD WATCH IN EFFECT THROUGH WEDNESDAY AFTERNOON...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS EXPANDED THE

* FLASH FLOOD WATCH TO INCLUDE NEW CASTLE COUNTY IN DELAWARE.

* THROUGH WEDNESDAY AFTERNOON

* A COMPLEX LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY
  INTO OUR REGION LATE TONIGHT AND PRODUCE RAINFALL TOTALS MAINLY
  IN THE 1.5 TO 2.5 INCH RANGE. THE RAIN WILL BE HEAVY AT TIMES
  OVERNIGHT AND ON WEDNESDAY MORNING AS THE SYSTEM WRAPS UP AND
  MOVES TO OUR NORTHEAST.

* IMPACTS WILL INCLUDE SMALL STREAM, POOR DRAINAGE, URBAN AREA,
  BASEMENT AND ROADWAY FLOODING. THE MAIN STEM RIVERS SHOULD BE
  ABLE TO TAKE THE EXCESSIVE RAINFALL WITHOUT FLOODING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING.

YOU SHOULD MONITOR THE FORECAST AND BE PREPARED TO TAKE ACTION
IF A FLASH FLOOD WARNING IS ISSUED.

&&

$$

NJZ001-007>010-012-015-PAZ060>062-067>071-231100-
/O.CON.KPHI.FF.A.0010.111123T0300Z-111123T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-BERKS-
LEHIGH-NORTHAMPTON-CHESTER-MONTGOMERY-BUCKS-DELAWARE-PHILADELPHIA-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...READING...
ALLENTOWN...BETHLEHEM...EASTON...WEST CHESTER...NORRISTOWN...
DOYLESTOWN...MEDIA...PHILADELPHIA
928 PM EST TUE NOV 22 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH WEDNESDAY
AFTERNOON...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF NEW JERSEY AND PENNSYLVANIA...INCLUDING THE
  FOLLOWING COUNTIES...IN NEW JERSEY...HUNTERDON...MERCER...
  MIDDLESEX...MORRIS...SOMERSET...SUSSEX AND WARREN. IN
  PENNSYLVANIA...BERKS...BUCKS...CHESTER...DELAWARE...LEHIGH...
  MONTGOMERY...NORTHAMPTON AND PHILADELPHIA.

* THROUGH WEDNESDAY AFTERNOON

* A COMPLEX LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY
  INTO OUR REGION LATE TONIGHT AND PRODUCE RAINFALL TOTALS MAINLY
  IN THE 1.5 TO 2.5 INCH RANGE. THE RAIN WILL BE HEAVY AT TIMES
  OVERNIGHT AND ON WEDNESDAY MORNING AS THE SYSTEM WRAPS UP AND
  MOVES TO OUR NORTHEAST.

* IMPACTS WILL INCLUDE SMALL STREAM, POOR DRAINAGE, URBAN AREA,
  BASEMENT AND ROADWAY FLOODING. THE MAIN STEM RIVERS SHOULD BE
  ABLE TO TAKE THE EXCESSIVE RAINFALL WITHOUT FLOODING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING.

YOU SHOULD MONITOR THE FORECAST AND BE PREPARED TO TAKE ACTION
IF A FLASH FLOOD WARNING IS ISSUED.

&&

$$
007 
WGUS61 KPHI 230813
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
313 AM EST WED NOV 23 2011

PAZ054-055-231800-
/O.EXA.KPHI.FF.A.0010.000000T0000Z-111123T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CARBON-MONROE-
INCLUDING THE CITIES OF...JIM THORPE...STROUDSBURG
313 AM EST WED NOV 23 2011

...FLASH FLOOD WATCH IN EFFECT UNTIL 1 PM EST THIS AFTERNOON...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS EXPANDED THE

* FLASH FLOOD WATCH TO INCLUDE A PORTION OF NORTHEAST 
  PENNSYLVANIA...INCLUDING THE FOLLOWING AREAS...CARBON AND 
  MONROE. 

* UNTIL 1 PM EST THIS AFTERNOON

* UP TO 2 INCHES OF RAIN HAS FALLEN ACROSS THE REGION THROUGH
  EARLY THIS MORNING. ADDITIONAL HEAVY RAIN THIS MORNING COULD
  RESULT IN FLOODING OF CREEKS AND STREAMS ACROSS THE REGION.

* IMPACTS WILL INCLUDE SMALL STREAM... POOR DRAINAGE... URBAN 
  AREA... BASEMENT AND ROADWAY FLOODING. THE MAIN STEM RIVERS 
  SHOULD BE ABLE TO TAKE THE EXCESSIVE RAINFALL WITHOUT 
  FLOODING. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING.

YOU SHOULD MONITOR THE FORECAST AND BE PREPARED TO TAKE ACTION IF
A FLASH FLOOD WARNING IS ISSUED.

&&

$$

DEZ001-NJZ001-007>010-012-015-PAZ060>062-067>071-231800-
/O.CON.KPHI.FF.A.0010.000000T0000Z-111123T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE-SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-
MERCER-BERKS-LEHIGH-NORTHAMPTON-CHESTER-MONTGOMERY-BUCKS-DELAWARE-
PHILADELPHIA-
INCLUDING THE CITIES OF...WILMINGTON...NEWTON...WASHINGTON...
MORRISTOWN...FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...
READING...ALLENTOWN...BETHLEHEM...EASTON...WEST CHESTER...
NORRISTOWN...DOYLESTOWN...MEDIA...PHILADELPHIA
313 AM EST WED NOV 23 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 1 PM EST THIS
AFTERNOON...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF NORTHERN DELAWARE...NEW JERSEY AND PENNSYLVANIA... 
  INCLUDING THE FOLLOWING AREAS...IN NORTHERN DELAWARE...NEW 
  CASTLE. IN NEW JERSEY...HUNTERDON...MERCER...MIDDLESEX... 
  MORRIS...SOMERSET...SUSSEX AND WARREN. IN PENNSYLVANIA... 
  BERKS...BUCKS...CHESTER...DELAWARE...LEHIGH...MONTGOMERY... 
  NORTHAMPTON AND PHILADELPHIA. 

* UNTIL 1 PM EST THIS AFTERNOON

* BETWEEN 1 AND 2 INCHES OF RAIN HAS FALLEN ACROSS THE REGION THIS
  MORNING...AND THIS HAS RESULTED IN FLOODING OF SMALL RIVERS AND
  STREAMS. ADDITIONAL HEAVY RAIN THIS MORNING COULD RESULT IN MORE
  FLOODING PROBLEMS.

* IMPACTS WILL INCLUDE SMALL STREAM... POOR DRAINAGE... URBAN 
  AREA... BASEMENT AND ROADWAY FLOODING. THE MAIN STEM RIVERS 
  SHOULD BE ABLE TO TAKE THE EXCESSIVE RAINFALL WITHOUT 
  FLOODING. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING.

YOU SHOULD MONITOR THE FORECAST AND BE PREPARED TO TAKE ACTION IF
A FLASH FLOOD WARNING IS ISSUED.

&&

$$
606 
WGUS61 KPHI 231134
FFAPHI

FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
634 AM EST WED NOV 23 2011

DEZ001-NJZ001-007>010-012-015-PAZ054-055-060>062-067>071-231245-
/O.CAN.KPHI.FF.A.0010.000000T0000Z-111123T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE-SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-
MERCER-CARBON-MONROE-BERKS-LEHIGH-NORTHAMPTON-CHESTER-MONTGOMERY-
BUCKS-DELAWARE-PHILADELPHIA-
INCLUDING THE CITIES OF...WILMINGTON...NEWTON...WASHINGTON...
MORRISTOWN...FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...
JIM THORPE...STROUDSBURG...READING...ALLENTOWN...BETHLEHEM...
EASTON...WEST CHESTER...NORRISTOWN...DOYLESTOWN...MEDIA...
PHILADELPHIA
631 AM EST WED NOV 23 2011

...FLASH FLOOD WATCH IS CANCELLED...

THE FLASH FLOOD WATCH FOR PORTIONS OF NORTHERN DELAWARE...NEW
JERSEY AND PENNSYLVANIA HAS BEEN CANCELLED. WHILE SHOWERS WILL
CONTINUE THIS MORNING...THE THREAT FOR ADDITIONAL WIDESPREAD HEAVY 
RAIN HAS PAST.

FLOODING IS OCCURRING IN SOME PLACES...AND RUNOFF WILL CONTINUE
THIS MORNING. MONITOR THE LATEST STATEMENTS AND WARNINGS
CONCERNING THE ONGOING FLOODING.
 
$$

HAYES

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 22, 1:43 AM ESTCoastal Flood StatementPHIAtlantic, Burlington, Middlesex, Monmouth, Ocean4 hr
Nov 22, 11:20 AM ESTGale WatchPHI10 hr
Nov 22, 2:45 PM ESTCoastal Flood StatementPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 4 more7 hr
Nov 22, 5:54 PM ESTAreal Flood AdvisoryPHIBerks, Bucks, Chester, Lehigh, Montgomery, Northampton6 hr

Nearby

Flash Flood Watches in New Jersey, 2011Flash Flood Watches in Pennsylvania, 2011Flash Flood Watches in Delaware, 2011Every flash flood watch in 2011

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.