Alert archive / New Jersey / Flood Watches in 2011

Flood Watch 7, NWS Philadelphia/Mount Holly

April 27, 20114 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flood watch at Apr 27, 2011, 3:30 AM EDT for 4 counties in New Jersey. It took effect at Apr 28, 2011, 10:00 AM EDT. It was in force for .

The area

The counties it named.

The facts

Issued
Apr 27, 2011, 3:30 AM EDT (07:30 UTC)
In effect from
Apr 28, 2011, 10:00 AM EDT
Expired
Apr 27, 2011, 3:26 PM EDT
In force
Issued by
NWS Philadelphia/Mount Holly
Flood severity
None

Counties Mercer County, NJ, Middlesex County, NJ, Morris County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 67 km from the middle of the area, began a volume at 07:34 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, 7.5 hours before the alert went out and 148 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, Brookhaven, NY at 00:00Z on 2011-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 15 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, Brookhaven, NY at 00:00Z on 2011-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 119 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
15 J/kg
Mixed-layer CIN
-252 J/kg
Mixed-layer LCL
541 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
119 m²/s²
0-3 km storm-relative helicity
157 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.

437 
WGUS61 KPHI 270730
FFAPHI

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

...HEAVY RAIN AT TIMES THURSDAY MAY LEAD TO FLOODING ON AREA
STREAMS AND PERHAPS THE LARGER RIVERS AS WELL...

.A SLOW-MOVING COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY...
AND MAY CAUSE A PERIOD OF HEAVY RAIN ESPECIALLY FROM LATE MORNING
AND THROUGH THURSDAY AFTERNOON.

NJZ008-010-012-015-272100-
/O.NEW.KPHI.FA.A.0007.110428T1400Z-110429T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MORRIS-SOMERSET-MIDDLESEX-MERCER-
INCLUDING THE CITIES OF...MORRISTOWN...SOMERVILLE...
NEW BRUNSWICK...TRENTON
330 AM EDT WED APR 27 2011

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A

* 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 LATER THURSDAY MORNING INTO THURSDAY EVENING.

* RAINFALL TOTALS AROUND 1 INCH ARE EXPECTED...WITH LOCAL AMOUNTS
  OF 1.5 TO 2 INCHES.

* THIS RAINFALL MAY LEAD TO FLOODING ON STREAMS AND CREEKS...AS
  WELL AS FLOODING OF ROADS, HIGHWAYS, AND AREAS OF POOR
  DRAINAGE. SOME FLOODING OF THE LARGER RIVERS MAY FOLLOW.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLOOD WATCH MEANS THERE IS A POTENTIAL FOR FLOODING BASED ON
CURRENT FORECASTS.

YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE FLOOD
WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE
PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP.

&&

$$
1 follow-up statement
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

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, 2:31 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester44 min
Apr 27, 3:26 PM EDTFlash Flood WatchPHIHunterdon, Mercer, Middlesex, Morris, Somerset, Sussex and 1 more24 hr
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

Nearby

Flood Watches in New Jersey, 2011Every 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.