Alert archive / Pennsylvania / Flash Flood Warnings in 2009

Flash Flood Warning 24, NWS Philadelphia/Mount Holly

July 31, 20094 states

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 31, 2009, 4:08 PM EDT for 4 states. It was in force for 3 hr. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 31, 2009, 4:08 PM EDT (20:08 UTC)
Expired: Jul 31, 2009, 6:48 PM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties New Castle County, DE, Cecil County, MD, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Salem County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Dover AFB radar (KDOX), 95 km from the middle of the area, began a volume at 20:10 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.

What was reported inside it

Time	Report	Where	Remark
Jul 31, 5:00 PM EDT	HEAVY RAIN 0	Stratford, NJ	1-2 FT OF WATER ON WHITE HORSE ROAD IN STRATFORD. ROADWAY IS IMPASSABLE.
Jul 31, 5:18 PM EDT	HEAVY RAIN 3.25	Pennsauken, NJ	3.25 INCHES OF RAIN WAS MEASURED IN 24 MINUTES IN PENNSAUKEN.
Jul 31, 5:28 PM EDT	HEAVY RAIN 1.52	Mount Holly, NJ	1.52 INCHES OF RAIN WAS MEASURED AT THE SOUTH JERSEY REGIONAL AIRPORT IN 34 MINUTES.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.1 hours before the alert went out and 178 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: 276 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 888 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: -25 m²/s²
0-3 km storm-relative helicity: 18 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.3

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 312008
FFWPHI
DEC003-MDC015-NJC005-007-015-033-PAC017-029-045-091-101-010000-
/O.NEW.KPHI.FF.W.0024.090731T2008Z-090801T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
408 PM EDT FRI JUL 31 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CECIL COUNTY IN NORTHEAST MARYLAND...
  THIS INCLUDES THE CITY OF ELKTON...
  NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK...MIDDLETOWN...
  SOUTHEASTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHEASTERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHEASTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF PHILADELPHIA...
  NORTHWESTERN BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...
  NORTHWESTERN CAMDEN COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF CAMDEN...
  NORTHWESTERN GLOUCESTER COUNTY IN SOUTHERN NEW JERSEY...
  NORTHWESTERN SALEM COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF SALEM...

* UNTIL 800 PM EDT

* AT 403 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  AN AREA OF EXCESSIVE RAINFALL OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PIKE
  CREEK...WISSINOMING...WESTTOWN...TROUT LAKE...TEMPLE UNIVERSITY...
  TACONY...SOUTH PHILADELPHIA...ROXBOROUGH...PHILADELPHIA
  INTERNATIONAL AIRPORT...NORTHEAST PHILADELPHIA...NEWTOWN SQUARE...
  MORRIS PARK...LADENBERG...KENSINGTON...KEMBLESVILLE...HOLMESBURG...
  GRADYVILLE...ELAM...CONCORDVILLE...CHEYNEY...CHESTNUT HILL...
  CHELSEA...CENTER CITY...BENSALEM...ANDALUSIA...ABINGTON...WEST
  DEPTFORD...SPRINGDALE...MOUNT LAUREL...JACKSONVILLE...GREENTREE...
  GEORGETOWN...DEPTFORD...NORTH STAR...HOCKESSIN...ASHLAND...
  GERMANTOWN...YEADON...WOODSIDE...WILLOW GROVE...SWARTHMORE...
  ROCKLEDGE...RICHBORO...RADNOR TOWNSHIP...PLYMOUTH MEETING...
  NORRISTOWN...NEWTOWN...NEW HOPE...NETHER PROVIDENCE TOWNSHIP...
  LIMA...LEVITTOWN...LANGHORNE...KING OF PRUSSIA...KENNETT SQUARE...
  IVYLAND...FOLCROFT...FEASTERVILLE...EAST LANSDOWNE...DREXEL HILL...
  CHESTER...BRYN MAWR...BROOMALL...BRISTOL...AMBLER...WOODBURY
  HEIGHTS...WOODBURY...WILLINGBORO...RIVERSIDE...PALMYRA...MULLICA
  HILL...MOUNT HOLLY...MARLTON...MAGNOLIA...GLOUCESTER CITY...
  GIBBSTOWN...FLORENCE...CHERRY HILL...BURLINGTON...BORDENTOWN...
  BEVERLY...BELLMAWR...BECKETT...TALLEYVILLE AND ELSMERE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNIN05 PM CDT FRI JUL 31 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0510 PM     TSTM WND DMG     BELLEFONTAINE           33.65N 89.31W 
07/30/2009                   WEBSTER            MS   LAW ENFORCEMENT 

            REPORTS OF AT LEAST 3 TREES ACROSS ROADS


&&

$$

HAMRICK

2 follow-up statements

000 
WGUS71 KPHI 312142
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
542 PM EDT FRI JUL 31 2009

DEC003-MDC015-NJC005-007-015-033-PAC017-029-045-091-101-010000-
/O.CON.KPHI.FF.W.0024.000000T0000Z-090801T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CECIL MD-SALEM NJ-CAMDEN NJ-GLOUCESTER NJ-DELAWARE PA-PHILADELPHIA 
PA-CHESTER PA-MONTGOMERY PA-BUCKS PA-NEW CASTLE DE-BURLINGTON NJ-541 
PM EDT FRI JUL 31 2009

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM EDT FOR
NORTHWESTERN BURLINGTON...NEW CASTLE...SOUTHEASTERN BUCKS...
SOUTHEASTERN MONTGOMERY...SOUTHEASTERN CHESTER...PHILADELPHIA...
DELAWARE...NORTHWESTERN GLOUCESTER...NORTHWESTERN CAMDEN...
NORTHWESTERN SALEM AND CECIL COUNTIES...

AT 542 PM EDT...FRANKFORD CREEK IN PHILADELPHIA WAS OUT OF ITS 
BANKS. FLASH FLOODING WAS OCCURRING.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WILMINGTON
MANOR...WISSINOMING...WESTTOWN...TROUT LAKE...TEMPLE UNIVERSITY...
TACONY...SOUTH PHILADELPHIA...ROXBOROUGH...PHILADELPHIA INTERNATIONAL
AIRPORT...NORTHEAST PHILADELPHIA...NEWTOWN SQUARE...MORRIS PARK...
LADENBERG...KENSINGTON...KEMBLESVILLE...HOLMESBURG...GRADYVILLE...
ELAM...CONCORDVILLE...CHEYNEY...CHESTNUT HILL...CHELSEA...CENTER
CITY...BENSALEM...ANDALUSIA...ABINGTON...WEST DEPTFORD...
SPRINGDALE...MOUNT LAUREL...JACKSONVILLE...GREENTREE...GEORGETOWN...
DEPTFORD...GLEN WESTOVER...FAIR HILL...APPLETON...NORTH STAR...
HOCKESSIN...ASHLAND...GERMANTOWN...YEADON...WOODSIDE...WILLOW
GROVE...SWARTHMORE...ROCKLEDGE...RICHBORO...RADNOR TOWNSHIP...
PLYMOUTH MEETING...PHILADELPHIA...NORRISTOWN...NEWTOWN...NEW HOPE...
NETHER PROVIDENCE TOWNSHIP...LIMA...LEVITTOWN...LANGHORNE...KING OF
PRUSSIA...KENNETT SQUARE...IVYLAND...FOLCROFT...FEASTERVILLE...EAST
LANSDOWNE...DREXEL HILL...CHESTER...BRYN MAWR...BROOMALL...BRISTOL...
AMBLER...WOODBURY HEIGHTS...WOODBURY...WILLINGBORO...RIVERSIDE...
PALMYRA...MULLICA HILL...MOUNT HOLLY...MARLTON...MAGNOLIA...
GLOUCESTER CITY...GIBBSTOWN...FLORENCE...CHERRY HILL...CARNEYS
POINT...CAMDEN...BURLINGTON...BORDENTOWN...BEVERLY...BELLMAWR...
BECKETT...WILMINGTON...TALLEYVILLE...STANTON...PIKE CREEK...NEWPORT
AND ELSMERE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.  
DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN 
DEPTH BY FOOT OR BY AUTOMOBILE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA.

&&

LAT...LON 3947 7554 3957 7553 3958 7556 3945 7558
      3938 7577 3937 7589 3938 7603 3941 7605
      3945 7600 3946 7602 3955 7598 3954 7607
      3957 7611 4040 7498 4032 7493 4015 7472
      4017 7468 4012 7459

$$

KRUZDLO

000 
WGUS71 KPHI 312248
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
648 PM EDT FRI JUL 31 2009

DEC003-MDC015-NJC005-007-015-033-PAC017-029-045-091-101-312256-
/O.CAN.KPHI.FF.W.0024.000000T0000Z-090801T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CECIL MD-SALEM NJ-CAMDEN NJ-GLOUCESTER NJ-DELAWARE PA-PHILADELPHIA 
PA-CHESTER PA-MONTGOMERY PA-BUCKS PA-NEW CASTLE DE-BURLINGTON NJ-
648 PM EDT FRI JUL 31 2009

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR NORTHWESTERN
BURLINGTON...NEW CASTLE...SOUTHEASTERN BUCKS...SOUTHEASTERN
MONTGOMERY...SOUTHEASTERN CHESTER...PHILADELPHIA...DELAWARE...
NORTHWESTERN GLOUCESTER...NORTHWESTERN CAMDEN...NORTHWESTERN SALEM
AND CECIL COUNTIES...

THE HEAVY RAIN RESPONSIBLE FOR THIS EVENINGS FLOODING HAS MOVED TO 
THE EAST. FRANKFORD CREEK IS NOW BACK IN ITS BANKS. 

THE FLASH FLOOD WARNING HAS BEEN CANCELLED. 

LAT...LON 3947 7554 3957 7553 3958 7556 3945 7558
      3938 7577 3937 7589 3938 7603 3941 7605
      3945 7600 3946 7602 3955 7598 3954 7607
      3957 7611 4040 7498 4032 7493 4015 7472
      4017 7468 4012 7459

$$

KRUZDLO

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 2:13 PM EDT	Flash Flood Warning	PHI	Carbon, Monroe	4 hr
Jul 31, 3:04 PM EDT	Flash Flood Warning	PHI	Bucks, Chester, Montgomery	3 hr
Jul 31, 3:36 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	54 min
Jul 31, 3:40 PM EDT	Severe Thunderstorm Warning	PHI	Chester	65 min
Jul 31, 4:03 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	57 min
Jul 31, 4:31 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	59 min
Jul 31, 2:36 PM EDT	Flash Flood Warning	PHI	Hunterdon, Morris, Sussex, Warren	4 hr
Jul 31, 4:23 PM EDT	Special Marine Warning	PHI		67 min
Jul 31, 4:39 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more	96 min
Jul 31, 4:56 PM EDT	Flash Flood Warning	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset	114 min
Jul 31, 5:07 PM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Camden, Cumberland, Gloucester, Salem	3 hr
Jul 31, 5:10 PM EDT	Tornado Warning	PHI	Burlington, Ocean	21 min
Jul 31, 5:14 PM EDT	Special Marine Warning	PHI		2 hr
Jul 31, 5:15 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Ocean	60 min
Jul 31, 5:16 PM EDT	Special Marine Warning	PHI		119 min
Jul 31, 5:31 PM EDT	Flash Flood Warning	PHI	Burlington, Monmouth, Ocean	4 hr
Jul 31, 5:48 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Cumberland, Ocean	3 hr
Jul 31, 3:10 PM EDT	Severe Thunderstorm Warning	PHI	Cecil, Kent	65 min
Jul 31, 3:54 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Kent, Queen Anne's	53 min
Jul 31, 4:12 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle, Sussex	73 min
Jul 31, 4:36 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	54 min

Nearby

Flash Flood Warnings in Pennsylvania, 2009 Flash Flood Warnings in New Jersey, 2009 Flash Flood Warnings in Maryland, 2009 Every flash flood warning in 2009

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.