Alert archive / New Jersey / Flash Flood Watches in 2011

Flash Flood Watch 1, NWS Philadelphia/Mount Holly

April 27, 20117 counties in New Jersey; 4 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood watch at Apr 27, 2011, 3:26 PM EDT for 7 counties in New Jersey; 4 counties in Pennsylvania. It took effect at Apr 28, 2011, 6:00 AM EDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Apr 27, 2011, 3:26 PM EDT (19:26 UTC)
In effect from
Apr 28, 2011, 6:00 AM EDT
Expired
Apr 28, 2011, 3:07 PM EDT
In force
9 hr
Issued by
NWS Philadelphia/Mount Holly
Flood severity
None

Counties Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 100 km from the middle of the area, began a volume at 19:29 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, 7.4 hours before the alert went out and 169 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 2011-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 139 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 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 2011-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 square meters per square second.193958Sfc1 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
139 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
640 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
84 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.

794 
WGUS61 KPHI 271926
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
326 PM EDT WED APR 27 2011

...VERY HEAVY DOWNPOURS AT TIMES THURSDAY...

.A COLD FRONT WILL SWEEP ACROSS THE AREA DURING THURSDAY WITH 
SHOWERS AND THUNDERSTORMS ACCOMPANYING IT. SOME OF THE STORMS MAY 
PRODUCE LOCALLY VERY HEAVY RAINFALL, WHICH COULD LEAD TO FLASH 
FLOODING.

NJZ008-010-012-015-280800-
/O.CAN.KPHI.FA.A.0007.110428T1400Z-110429T0200Z/
/O.NEW.KPHI.FF.A.0001.110428T1400Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MORRIS-SOMERSET-MIDDLESEX-MERCER-
INCLUDING THE CITIES OF...MORRISTOWN...SOMERVILLE...
NEW BRUNSWICK...TRENTON
326 PM EDT WED APR 27 2011

...FLASH FLOOD WATCH IN EFFECT FROM THURSDAY MORNING THROUGH
THURSDAY EVENING...
...FLOOD WATCH IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A

* FLASH FLOOD WATCH FOR PORTIONS OF CENTRAL NEW JERSEY AND 
 NORTHERN NEW JERSEY...INCLUDING THE FOLLOWING AREAS...IN 
 CENTRAL NEW JERSEY...MERCER. IN NORTHERN NEW JERSEY...
 MIDDLESEX...MORRIS AND SOMERSET.

* FROM THURSDAY MORNING THROUGH THURSDAY EVENING.

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT ON   
  THURSDAY HAVE THE POTENTIAL TO PRODUCE ONE INCH OR MORE OF         
  RAINFALL IN A SHORT PERIOD OF TIME. THE GROUND REMAINS             
  SATURATED AND ANY ADDITIONAL HEAVY DOWNPOURS IN A SHORT PERIOD OF  
  TIME COULD LEAD TO AREAS OF FLASH FLOODING. 

* THE QUICK HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON RIVERS
  AND CREEKS, AS WELL AS ON ROADWAYS AND AREAS OF POOR DRAINAGE.
  QUICK RESPONDING RIVERS AND SMALL STREAMS ALSO HAVE THE
  POTENTIAL TO EXCEED BANKFULL.

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.

$$

NJZ001-007-009-PAZ054-055-061-062-280800-
/O.NEW.KPHI.FF.A.0001.110428T1400Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-HUNTERDON-CARBON-MONROE-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...FLEMINGTON...
JIM THORPE...STROUDSBURG...ALLENTOWN...BETHLEHEM...EASTON
326 PM EDT WED APR 27 2011

...FLASH FLOOD WATCH IN EFFECT FROM THURSDAY MORNING THROUGH
THURSDAY EVENING...

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...SUSSEX AND WARREN. IN PENNSYLVANIA...CARBON...
 LEHIGH...MONROE AND NORTHAMPTON.

* FROM THURSDAY MORNING THROUGH THURSDAY EVENING.

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT ON
  THURSDAY HAVE THE POTENTIAL TO PRODUCE ONE INCH OR MORE OF
  RAINFALL IN A SHORT PERIOD OF TIME. THE GROUND IS SATURATED AND
  ANY HEAVY DOWNPOURS IN A SHORT PERIOD OF TIME COULD LEAD TO
  AREAS OF FLASH FLOODING.

* THE QUICK HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON RIVERS
  AND CREEKS, AS WELL AS ON ROADWAYS AND AREAS OF POOR DRAINAGE.
  QUICK RESPONDING RIVERS AND SMALL STREAMS ALSO HAVE THE
  POTENTIAL TO EXCEED BANKFULL.

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.

&&

$$

GORSE
6 follow-up statements
540 
WGUS61 KPHI 280050
FFAPHI

FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
850 PM EDT WED APR 27 2011

...VERY HEAVY DOWNPOURS AT TIMES THURSDAY...

.A COLD FRONT WILL SWEEP ACROSS THE AREA DURING THURSDAY WITH
SHOWERS AND THUNDERSTORMS ACCOMPANYING IT. SOME OF THE STORMS MAY
PRODUCE LOCALLY VERY HEAVY RAINFALL, WHICH COULD LEAD TO FLASH
FLOODING.

NJZ001-007>010-012-015-PAZ054-055-061-062-280830-
/O.CON.KPHI.FF.A.0001.110428T1400Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-CARBON-
MONROE-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...JIM THORPE...
STROUDSBURG...ALLENTOWN...BETHLEHEM...EASTON
850 PM EDT WED APR 27 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM THURSDAY MORNING
THROUGH THURSDAY EVENING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF NEW JERSEY AND PENNSYLVANIA...INCLUDING THE 
  FOLLOWING AREAS...IN NEW JERSEY...HUNTERDON...MERCER...
  MIDDLESEX...MORRIS...SOMERSET...SUSSEX AND WARREN. IN 
  PENNSYLVANIA...CARBON...LEHIGH...MONROE AND NORTHAMPTON.

* FROM THURSDAY MORNING THROUGH THURSDAY EVENING.

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT ON
  THURSDAY HAVE THE POTENTIAL TO PRODUCE ONE INCH OR MORE OF
  RAINFALL IN A SHORT PERIOD OF TIME. THE GROUND IS SATURATED AND
  ANY HEAVY DOWNPOURS IN A SHORT PERIOD OF TIME COULD LEAD TO
  AREAS OF FLASH FLOODING.

* THE QUICK HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON RIVERS
  AND CREEKS, AS WELL AS ON ROADWAYS AND AREAS OF POOR DRAINAGE.
  QUICK RESPONDING RIVERS AND SMALL STREAMS ALSO HAVE THE
  POTENTIAL TO EXCEED BANKFULL.

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.

$$

GORSE
299 
WGUS61 KPHI 280730
FFAPHI

FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
330 AM EDT THU APR 28 2011

...VERY HEAVY DOWNPOURS AT TIMES TODAY...

.A COLD FRONT WILL MOVE SLOWLY THROUGH OUR AREA THIS AFTERNOON AND
INTO THIS EVENING...WITH SHOWERS AND THUNDERSTORMS ACCOMPANYING
IT. SOME OF THE STORMS WILL PRODUCE LOCALLY VERY HEAVY RAINFALL...
WHICH COULD LEAD TO FLASH FLOODING.

NJZ001-007>010-012-015-PAZ054-055-061-062-281600-
/O.CON.KPHI.FF.A.0001.110428T1400Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-CARBON-
MONROE-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...JIM THORPE...
STROUDSBURG...ALLENTOWN...BETHLEHEM...EASTON
330 AM EDT THU APR 28 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 10 AM EDT THIS
MORNING THROUGH THIS EVENING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF NEW JERSEY AND PENNSYLVANIA...INCLUDING THE 
 FOLLOWING AREAS...IN NEW JERSEY...HUNTERDON...MERCER...
 MIDDLESEX...MORRIS...SOMERSET...SUSSEX AND WARREN. IN 
 PENNSYLVANIA...CARBON...LEHIGH...MONROE AND NORTHAMPTON.

* FROM 10 AM EDT THIS MORNING THROUGH THIS EVENING

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT
  ARE FORECAST TO PRODUCE THREE QUARTERS OF AN INCH TO ONE INCH OF
  RAIN IN A SHORT PERIOD OF TIME TODAY. LOCAL AMOUNTS MAY BE NEAR
  ONE AND A HALF INCHES. THE GROUND IS MOSTLY STILL VERY WET...AND
  EXPECTED HEAVY DOWNPOURS IN A SHORT PERIOD OF TIME COULD LEAD TO
  AREAS OF FLASH FLOODING.

* THE HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON STREAMS AND
  CREEKS...AS WELL AS ON ROADWAYS AND IN AREAS OF POOR DRAINAGE.
  THE QUICKER-RESPONDING RIVERS WILL HAVE SIGNIFICANT RISES AND
  HAVE THE POTENTIAL TO EXCEED BANKFULL AS WELL.

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.

$$
449 
WGUS61 KPHI 280813
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
413 AM EDT THU APR 28 2011

...VERY HEAVY DOWNPOURS AT TIMES TODAY...

.A COLD FRONT WILL MOVE SLOWLY THROUGH OUR AREA THIS AFTERNOON
AND INTO THIS EVENING...WITH SHOWERS AND THUNDERSTORMS PRECEDING
AND ACCOMPANYING IT. SOME OF THE STORMS WILL PRODUCE LOCALLY
VERY HEAVY RAINFALL...WHICH COULD LEAD TO FLASH FLOODING. 

NJZ001-007>010-012-015-PAZ054-055-061-062-281600-
/O.EXT.KPHI.FF.A.0001.110428T1000Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-CARBON-
MONROE-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...JIM THORPE...
STROUDSBURG...ALLENTOWN...BETHLEHEM...EASTON
413 AM EDT THU APR 28 2011

...FLASH FLOOD WATCH NOW IN EFFECT THROUGH THIS EVENING...

THE FLASH FLOOD WATCH IS NOW IN EFFECT FOR

* PORTIONS OF NEW JERSEY AND PENNSYLVANIA...INCLUDING THE 
 FOLLOWING AREAS...IN NEW JERSEY...HUNTERDON...MERCER...
 MIDDLESEX...MORRIS...SOMERSET...SUSSEX AND WARREN. IN 
 PENNSYLVANIA...CARBON...LEHIGH...MONROE AND NORTHAMPTON.

* THROUGH THIS EVENING

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT 
 ARE FORECAST TO PRODUCE THREE QUARTERS OF AN INCH TO ONE INCH 
 OF RAIN IN A SHORT PERIOD OF TIME TODAY. LOCAL AMOUNTS MAY BE 
 NEAR ONE AND A HALF INCHES. THE GROUND IS MOSTLY STILL VERY 
 WET...AND EXPECTED HEAVY DOWNPOURS IN A SHORT PERIOD OF TIME 
 COULD LEAD TO AREAS OF FLASH FLOODING. 

* THE HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON STREAMS AND 
 CREEKS...AS WELL AS ON ROADWAYS AND IN AREAS OF POOR DRAINAGE. 
 THE QUICKER-RESPONDING RIVERS WILL HAVE SIGNIFICANT RISES AND 
 HAVE THE POTENTIAL TO EXCEED BANKFULL AS WELL. 

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.

$$
638 
WGUS61 KPHI 281617
FFAPHI

FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1217 PM EDT THU APR 28 2011

...VERY HEAVY DOWNPOURS AT TIMES TODAY...

.A COLD FRONT WILL MOVE SLOWLY THROUGH OUR AREA THIS AFTERNOON
AND INTO THIS EVENING...WITH SHOWERS AND THUNDERSTORMS PRECEDING
AND ACCOMPANYING IT. SOME OF THE STORMS WILL PRODUCE LOCALLY VERY
HEAVY RAINFALL...WHICH COULD LEAD TO FLASH FLOODING.

NJZ001-007>010-012-015-PAZ054-055-061-062-290200-
/O.CON.KPHI.FF.A.0001.000000T0000Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-CARBON-
MONROE-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...SOMERVILLE...NEW BRUNSWICK...TRENTON...JIM THORPE...
STROUDSBURG...ALLENTOWN...BETHLEHEM...EASTON
1217 PM EDT THU APR 28 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF NEW JERSEY AND PENNSYLVANIA...INCLUDING THE 
 FOLLOWING AREAS...IN NEW JERSEY...HUNTERDON...MERCER...
 MIDDLESEX...MORRIS...SOMERSET...SUSSEX AND WARREN. IN 
 PENNSYLVANIA...CARBON...LEHIGH...MONROE AND NORTHAMPTON.

* UNTIL 10 PM EDT THIS EVENING

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT 
 ARE FORECAST TO PRODUCE THREE QUARTERS OF AN INCH TO ONE INCH 
 OF RAIN IN A SHORT PERIOD OF TIME TODAY. LOCAL AMOUNTS MAY BE 
 NEAR ONE AND A HALF INCHES. THE GROUND IS MOSTLY STILL VERY 
 WET...AND EXPECTED HEAVY DOWNPOURS IN A SHORT PERIOD OF TIME 
 COULD LEAD TO AREAS OF FLASH FLOODING. 

* THE HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON STREAMS AND 
 CREEKS...AS WELL AS ON ROADWAYS AND IN AREAS OF POOR DRAINAGE. 
 THE QUICKER-RESPONDING RIVERS WILL HAVE SIGNIFICANT RISES AND 
 HAVE THE POTENTIAL TO EXCEED BANKFULL AS WELL. 

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.

$$
552 
WGUS61 KPHI 281742
FFAPHI

FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
142 PM EDT THU APR 28 2011

NJZ001-007>009-PAZ054-055-061-062-281845-
/O.CAN.KPHI.FF.A.0001.000000T0000Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX-WARREN-MORRIS-HUNTERDON-CARBON-MONROE-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...JIM THORPE...STROUDSBURG...ALLENTOWN...BETHLEHEM...
EASTON
142 PM EDT THU APR 28 2011

...FLASH FLOOD WATCH IS CANCELLED...

THE FLASH FLOOD WATCH FOR PORTIONS OF NEW JERSEY AND PENNSYLVANIA
HAS BEEN CANCELLED. MOST OF THE HEAVIEST RAINS HAVE MOVED TO THE
EAST. ANY ADDITIONAL SHOWERS WILL PRODUCE ONLY LIGHT RAIN TOTALS. 

$$

NJZ010-012-015-290200-
/O.CON.KPHI.FF.A.0001.000000T0000Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SOMERSET-MIDDLESEX-MERCER-
INCLUDING THE CITIES OF...SOMERVILLE...NEW BRUNSWICK...TRENTON
142 PM EDT THU APR 28 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF CENTRAL NEW JERSEY AND NORTHERN NEW JERSEY...
 INCLUDING THE FOLLOWING AREAS...IN CENTRAL NEW JERSEY...
 MERCER. IN NORTHERN NEW JERSEY...MIDDLESEX AND SOMERSET.

* UNTIL 10 PM EDT THIS EVENING

* SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG COLD FRONT
  ARE FORECAST TO PRODUCE THREE QUARTERS OF AN INCH TO ONE INCH OF
  RAIN IN A SHORT PERIOD OF TIME THIS AFTERNOON. LOCAL AMOUNTS
  MAY BE NEAR ONE AND A HALF INCHES. THE GROUND IS MOSTLY STILL
  VERY WET...AND EXPECTED HEAVY DOWNPOURS IN A SHORT PERIOD OF
  TIME COULD LEAD TO AREAS OF FLASH FLOODING.

* THE HEAVY DOWNPOURS MAY LEAD TO FLASH FLOODING ON STREAMS AND 
 CREEKS...AS WELL AS ON ROADWAYS AND IN AREAS OF POOR DRAINAGE. 
 THE QUICKER-RESPONDING RIVERS WILL HAVE SIGNIFICANT RISES AND 
 HAVE THE POTENTIAL TO EXCEED BANK-FULL AS WELL. 

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.

$$
272 
WGUS61 KPHI 281907
FFAPHI

FLOOD WATCH
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
307 PM EDT THU APR 28 2011

NJZ010-012-015-282015-
/O.CAN.KPHI.FF.A.0001.000000T0000Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SOMERSET-MIDDLESEX-MERCER-
INCLUDING THE CITIES OF...SOMERVILLE...NEW BRUNSWICK...TRENTON
307 PM EDT THU APR 28 2011

...FLASH FLOOD WATCH IS CANCELLED...

THE FLASH FLOOD WATCH FOR PORTIONS OF CENTRAL NEW JERSEY AND
NORTHERN NEW JERSEY HAS BEEN CANCELLED. 

ONLY SCATTERED SHOWERS WILL BE ACROSS THE AREA THE REST OF THE
AFTERNOON INTO THE EVENING. ANY ADDITIONAL RAINFALL IS NOT
EXPECTED TO BE GREAT ENOUGH TO PRODUCE FLASH FLOODING. 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 26, 9:25 PM EDTMarine Dense Fog AdvisoryPHI6 hr
Apr 27, 12:08 AM EDTSpecial Weather StatementPHIMorris, Sussex, Warren67 min
Apr 27, 12:34 AM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren56 min
Apr 27, 12:43 AM EDTSpecial Weather StatementPHIHunterdon, Somerset62 min
Apr 27, 1:19 AM EDTSpecial Weather StatementPHIHunterdon, Mercer, Middlesex, Somerset56 min
Apr 27, 3:25 AM EDTSpecial Weather StatementPHIHunterdon, Morris65 min
Apr 27, 3:30 AM EDTFlood WatchPHIMercer, Middlesex, Morris, Somerset12 hr
Apr 27, 2:31 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester44 min
Apr 27, 3:29 PM EDTSpecial Weather StatementPHIMorris, Somerset61 min
Apr 27, 3:39 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset, Sussex66 min
Apr 27, 4:16 PM EDTSpecial Weather StatementPHISalem59 min
Apr 27, 4:43 PM EDTSpecial Weather StatementPHICamden, Cumberland, Gloucester, Salem62 min
Apr 27, 4:43 PM EDTSevere Thunderstorm WarningPHICumberland, Gloucester, Salem36 min
Apr 27, 4:50 PM EDTSpecial Marine WarningPHI12 min
Apr 27, 5:22 PM EDTSpecial Weather StatementPHIBurlington, Camden, Gloucester83 min
Apr 26, 10:01 PM EDTSpecial Weather StatementPHICarbon59 min
Apr 26, 10:55 PM EDTSpecial Weather StatementPHIMonroe50 min
Apr 26, 11:10 PM EDTSpecial Weather StatementPHIBerks65 min
Apr 26, 11:34 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon56 min
Apr 26, 11:41 PM EDTSpecial Weather StatementPHIMonroe64 min
Apr 26, 11:45 PM EDTSpecial Weather StatementPHILehigh, Northampton60 min
Apr 27, 1:48 PM EDTSpecial Weather StatementPHIDelaware, Montgomery, Philadelphia87 min

Nearby

Flash Flood Watches in New Jersey, 2011Flash Flood Watches in Pennsylvania, 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.