Alert archive / New Jersey / Flash Flood Warnings in 2017

Flash Flood Warning 5, NWS Philadelphia/Mount Holly

June 24, 2017Bucks County, Montgomery County, Philadelphia County, Pennsylvania; 4 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 24, 2017, 7:21 AM EDT for Bucks County, Montgomery County, Philadelphia County, Pennsylvania; 4 counties in New Jersey. It was in force for 4 hr. 2 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: Jun 24, 2017, 7:21 AM EDT (11:21 UTC)
Expired: Jun 24, 2017, 11:15 AM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Burlington County, NJ, Camden County, NJ, Mercer County, NJ, Somerset County, NJ, Bucks County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 47 km from the middle of the area, began a volume at 11:21 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
Jun 24, 9:45 AM EDT	FLASH FLOOD	Winchester Park, PA	GAUGE AT PENNYPACK CREEK IN PHILADELPHIA REACHED FLOOD STAGE AT 945 AM.
Jun 24, 9:58 AM EDT	HEAVY RAIN 3.25	Princeton Junction, NJ

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 11.4 hours before the alert went out and 179 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: 488 J/kg
Mixed-layer CIN: -80 J/kg
Mixed-layer LCL: 653 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 177 m²/s²
0-3 km storm-relative helicity: 213 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

As transmitted.

655 
WGUS51 KPHI 241121
FFWPHI
NJC005-007-021-035-PAC017-091-101-241515-
/O.NEW.KPHI.FF.W.0005.170624T1121Z-170624T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
721 AM EDT SAT JUN 24 2017

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Northwestern Camden County in southern New Jersey...
  Mercer County in central New Jersey...
  Northwestern Burlington County in southern New Jersey...
  Southwestern Somerset County in northern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Southeastern Bucks County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...

* Until 1115 AM EDT

* At 720 AM EDT...Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Up to 
  two inches of rain have already fallen. Area creeks and streams 
  are beginning to show indications of rapid response to runoff. 
  Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Philadelphia, Trenton, Camden, Gloucester City, Bensalem, Ewing,
  Willingboro, Princeton, Florence, Yeadon, Burlington, Bristol,
  Riverside, Palmyra, Hatboro, Folcroft, Hightstown, Jenkintown,
  Narberth and Bordentown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 4018 7461 4012 7459 3986 7521 3988 7527
      3994 7524 4002 7531 4038 7495 4034 7494
      4035 7486 4038 7487 4038 7481 4041 7481
      4047 7464 4044 7453 4042 7458 4034 7463
      4028 7449 4024 7448

$$

CMS

3 follow-up statements

543 
WGUS71 KPHI 241245
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
845 AM EDT SAT JUN 24 2017

NJC005-007-021-035-PAC017-091-101-241515-
/O.CON.KPHI.FF.W.0005.000000T0000Z-170624T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-Mercer NJ-Burlington NJ-Somerset NJ-Montgomery PA-Bucks PA-
Philadelphia PA-
845 AM EDT SAT JUN 24 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 AM EDT FOR
NORTHWESTERN CAMDEN...MERCER...NORTHWESTERN BURLINGTON...SOUTHWESTERN
SOMERSET...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN BUCKS AND
PHILADELPHIA COUNTIES...

At 843 AM EDT...Doppler radar and automated rain gauges indicated 
that one to two inches of rain occurred earlier this morning. 
Several reports of street flooding have been received, especially in 
Mercer County. Though the heavy rainfall has ended, rapid runoff 
from the storms is continuing. Flash flooding is expected to begin 
shortly.

Some locations that will experience flooding include...
Philadelphia, Trenton, Camden, Gloucester City, Bensalem, Ewing,
Willingboro, Princeton, Florence, Yeadon, Burlington, Bristol,
Riverside, Palmyra, Hatboro, Folcroft, Hightstown, Jenkintown,
Narberth and Bordentown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4018 7461 4012 7459 3986 7521 3988 7527
      3994 7524 4002 7531 4038 7495 4034 7494
      4035 7486 4038 7487 4038 7481 4041 7481
      4047 7464 4044 7453 4042 7458 4034 7463
      4028 7449 4024 7448

$$

CMS

734 
WGUS71 KPHI 241400
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1000 AM EDT SAT JUN 24 2017

NJC005-007-021-035-PAC017-091-101-241515-
/O.CON.KPHI.FF.W.0005.000000T0000Z-170624T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-Mercer NJ-Burlington NJ-Somerset NJ-Montgomery PA-Bucks PA-
Philadelphia PA-
1000 AM EDT SAT JUN 24 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 AM EDT FOR
NORTHWESTERN CAMDEN...MERCER...NORTHWESTERN BURLINGTON...SOUTHWESTERN
SOMERSET...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN BUCKS AND
PHILADELPHIA COUNTIES...

At 956 AM EDT...gauge reports indicated several creeks and streams 
are approaching or exceeding flood stage at this time. Street 
flooding is continuing in portions of Mercer County as well.

Some locations that will experience flooding include...
Philadelphia, Trenton, Camden, Gloucester City, Bensalem, Ewing,
Willingboro, Princeton, Florence, Yeadon, Burlington, Bristol,
Riverside, Palmyra, Hatboro, Folcroft, Hightstown, Jenkintown,
Narberth and Bordentown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. Act quickly to protect your life.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4018 7461 4012 7459 3986 7521 3988 7527
      3994 7524 4002 7531 4038 7495 4034 7494
      4035 7486 4038 7487 4038 7481 4041 7481
      4047 7464 4044 7453 4042 7458 4034 7463
      4028 7449 4024 7448

$$

CMS

108 
WGUS71 KPHI 241517
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1117 AM EDT SAT JUN 24 2017

NJC005-007-021-035-PAC017-091-101-241526-
/O.EXP.KPHI.FF.W.0005.000000T0000Z-170624T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-Mercer NJ-Burlington NJ-Somerset NJ-Montgomery PA-Bucks PA-
Philadelphia PA-
1117 AM EDT SAT JUN 24 2017

...THE FLASH FLOOD WARNING FOR NORTHWESTERN CAMDEN...MERCER...
NORTHWESTERN BURLINGTON...SOUTHWESTERN SOMERSET...SOUTHEASTERN
MONTGOMERY...SOUTHEASTERN BUCKS AND PHILADELPHIA COUNTIES HAS
EXPIRED...

The heavy rain has ended, and the threat of flash flooding has 
ended. However, a flood warning has been issued for Pennypack Creek 
in Philadelphia County until 215 pm EDT. Please continue to heed any 
remaining road closures.

LAT...LON 4018 7461 4012 7459 3986 7521 3988 7527
      3994 7524 4002 7531 4038 7495 4034 7494
      4035 7486 4038 7487 4038 7481 4041 7481
      4047 7464 4044 7453 4042 7458 4034 7463
      4028 7449 4024 7448

$$

CMS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 23, 8:54 PM EDT	Areal Flood Advisory	PHI	Northampton	3 hr
Jun 23, 9:23 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh, Northampton	112 min
Jun 23, 11:42 PM EDT	Areal Flood Advisory	PHI	Chester	4 hr
Jun 23, 11:58 PM EDT	Special Weather Statement	PHI	Philadelphia	47 min
Jun 24, 3:25 AM EDT	Areal Flood Advisory	PHI	Bucks, Lehigh, Monroe, Montgomery, Northampton	4 hr
Jun 24, 4:02 AM EDT	Areal Flood Advisory	PHI	Berks, Carbon, Lehigh, Montgomery	4 hr
Jun 24, 5:22 AM EDT	Areal Flood Advisory	PHI	Chester, Montgomery	4 hr
Jun 24, 7:09 AM EDT	Areal Flood Advisory	PHI	Bucks	4 hr
Jun 24, 11:16 AM EDT	Areal Flood Warning	PHI	Philadelphia	3 hr
Jun 24, 2:10 PM EDT	Areal Flood Warning	PHI	Philadelphia	110 min
Jun 24, 6:17 AM EDT	Special Marine Warning	PHI		28 min
Jun 24, 6:20 AM EDT	Special Weather Statement	PHI	Cumberland, Gloucester, Salem	55 min
Jun 24, 6:26 AM EDT	Tornado Warning	PHI	Burlington, Camden, Gloucester	34 min
Jun 24, 6:39 AM EDT	Tornado Warning	PHI	Mercer, Middlesex, Monmouth	36 min
Jun 24, 6:42 AM EDT	Special Marine Warning	PHI		63 min
Jun 24, 6:49 AM EDT	Special Weather Statement	PHI	Monmouth, Ocean	41 min
Jun 24, 6:58 AM EDT	Special Weather Statement	PHI	Burlington, Monmouth	32 min
Jun 24, 7:00 AM EDT	Special Weather Statement	PHI	Cape May	30 min
Jun 24, 7:02 AM EDT	Special Marine Warning	PHI		58 min
Jun 24, 7:19 AM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Cape May, Cumberland, Monmouth, Ocean	56 min
Jun 24, 7:20 AM EDT	Special Marine Warning	PHI		55 min
Jun 24, 7:26 AM EDT	Flash Flood Warning	PHI	Middlesex, Somerset	4 hr
Jun 24, 7:39 AM EDT	Special Marine Warning	PHI		66 min
Jun 24, 7:54 AM EDT	Special Marine Warning	PHI		66 min
Jun 24, 8:11 AM EDT	Special Marine Warning	PHI		64 min
Jun 24, 8:16 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Monmouth, Ocean	4 hr

Nearby

Flash Flood Warnings in New Jersey, 2017 Flash Flood Warnings in Pennsylvania, 2017 Every flash flood warning in 2017

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.