Alert archive / Pennsylvania / Flash Flood Warnings in 2018

Flash Flood Warning 16, NWS Philadelphia/Mount Holly

June 10, 20185 counties in Pennsylvania; Burlington County, Camden County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 10, 2018, 11:33 PM EDT for 5 counties in Pennsylvania; Burlington County, Camden County, New Jersey. It was in force for 5 hr. 23 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 10, 2018, 11:33 PM EDT (03:33 UTC)
Expired: Jun 11, 2018, 4:25 AM EDT
In force: 5 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Burlington County, NJ, Camden County, NJ, Berks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 79 km from the middle of the area, began a volume at 03:34 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.

What was reported inside it

Time	Report	Where	Remark
Jun 10, 11:48 PM EDT	HEAVY RAIN 2.93	1 N Germantown, PA	NEARLY 2.5 INCHES IN THE LAST 2 HOURS
Jun 10, 11:48 PM EDT	HEAVY RAIN 2.96	Chestnut Hill, PA	NEARLY 2.5 INCHES IN THE LAST 2 HOURS
Jun 10, 11:59 PM EDT	FLASH FLOOD	Brecknock Twp, PA	WATER RESCUE ON ALLEGHENYVILLE ROAD IN BRECKNOCK TWP.
Jun 11, 12:11 AM EDT	FLASH FLOOD	1 W Upper Merion Twp, PA	WATER RESCUE- SCHUYKILL EXPY AND CROTON RD UNDERPASS
Jun 11, 12:20 AM EDT	FLASH FLOOD	1 Ssw Conshohocken, PA	WATER RESCUE AT THE SCHUYKILL EXPY AND CONSHOHOCKEN STATE RD UNDERPASS
Jun 11, 12:28 AM EDT	FLASH FLOOD	Gulph Mills Village, PA	WEBCAMS INDICATING STANDING WATER ON INTERSTATE 76 NEAR WEADLEY ROAD WITH NO LANES PASSABLE. REPORT RELAYED VIA BROADCAST MEDIA.
Jun 11, 12:45 AM EDT	FLASH FLOOD	Willingboro Twp, NJ	MULTIPLE VEHICLES TRAPPED IN HIGH WATER AT LEVITT PKWY AND JFK WAY
Jun 11, 12:47 AM EDT	FLOOD	New Centerville, PA	FLOODING ON U.S. HIGHWAY 202 BETWEEN VALLEY FORGE ROAD AND STATE HIGHWAY 29.
Jun 11, 12:54 AM EDT	FLOOD	1 Sse Mayfair, PA	FLOODING ON INTERSTATE 95 AT COTTMAN AVENUE WITH RAMP CLOSURES IN PLACE.
Jun 11, 12:59 AM EDT	HEAVY RAIN 3.69	Mount Holly Wfo, NJ	3.69 INCHES OF RAIN IN THE LAST 3 HOURS.
Jun 11, 1:06 AM EDT	FLASH FLOOD	Tredyffrin Twp, PA	A RESIDENCE WAS FLOODING TO THE FIRST FLOOR NEAR YELLOW SPRINGS ROAD AND WELL SPRINGS LANE.
Jun 11, 1:06 AM EDT	FLASH FLOOD	Tredyffrin Twp, PA	A WATER RESCUE OCCURRED AT NORTH GULPH ROAD AND RICHARDS ROAD AND A SECOND AT RICHARDS ROAD AND GLEN HARDIE ROAD. THERE WERE SEVERAL STRANDED VEHICLES IN THIS AREA.
Jun 11, 1:20 AM EDT	FLASH FLOOD	1 E Delran Twp, NJ	ONGOING WATER RESCUES NEAR WILLOW BEND DRIVE WITH MULTIPLE VEHICLES TRAPPED IN HIGH WATER. FIVE OCCUPANTS REMOVED SO FAR.
Jun 11, 1:30 AM EDT	FLASH FLOOD	Valley Forge, PA	VALLEY RD IMPASSABLE DUE TO FLOOD WATERS
Jun 11, 1:53 AM EDT	FLASH FLOOD	1 Nw East Pennsauken, NJ	FLOODING ON U.S. HIGHWAY 130 BETWEEN STATE HIGHWAY 90 AND STATE HIGHWAY 73. ALL NORTHBOUND LANES CLOSED.
Jun 11, 1:57 AM EDT	HEAVY RAIN 4.31	Mount Holly Wfo, NJ	4.31 INCHES SINCE AROUND 10 PM.
Jun 11, 2:10 AM EDT	FLOOD	Cinnaminson, NJ	FLOODING ON U.S. HIGHWAY 130 NORTHBOUND APPROACHING RIVERTON ROAD. RIGHT AND CENTER LANES IMPASSABLE.
Jun 11, 2:27 AM EDT	FLASH FLOOD	1 Ne Pikeland, PA	FLOODING ON CLOVER MILL ROAD AND PIKELAND ROAD BETWEEN KIMBERTON ROAD AND WILDLIFE DRIVE. ALL LANES CLOSED.
Jun 11, 2:30 AM EDT	FLOOD	1 Se Timbuctoo, NJ	RANCOCAS ROAD (CO. RD. 626) CLOSED NEAR MOUNT HOLLY BYPASS (CO. RD. 541). TIME ESTIMATED FROM RADAR.
Jun 11, 2:30 AM EDT	FLOOD	Rittenhouse Town, PA	LINCOLN DRIVE CLOSED BETWEEN WISSAHICKON AVENUE AND JOHNSON STREET FROM FLOODING. TIME ESTIMATED BASED ON RADAR AND NEARBY REPORTS.
Jun 11, 2:56 AM EDT	FLOOD	1 Ene Knauertown, PA	HEAVY RAIN AND FLOODING DOWNED A TREE INTO POWER LINES ON STATE HIGHWAY 23 BETWEEN OLD RIDGE ROAD AND POTTSTOWN PIKE. ALL LANES CLOSED.
Jun 11, 3:29 AM EDT	FLOOD	1 Se Richmond, PA	FLOODING ON INTERSTATE 95 NORTHBOUND NEAR BETSY ROSS BRIDGE. LANE RESTRICTIONS IN PLACE.
Jun 11, 4:23 AM EDT	FLOOD	1 Se Valley Forge Mount, PA	FLOODING CAUSED DEBRIS TO COLLECT ON THE ROADWAY ON YELLOW SPRINGS ROAD BETWEEN WILSON ROAD AND GLEN ALEXANDER DRIVE. LANE RESTRICTIONS IN PLACE.

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 00:00Z, 3.6 hours before the alert went out and 219 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: 525 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 747 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 87 m²/s²
0-3 km storm-relative helicity: 205 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 3.2

Open this sounding in Storm Lab

The text

As transmitted.

578 
WGUS51 KPHI 110333
FFWPHI
NJC005-007-PAC011-029-045-091-101-110930-
/O.NEW.KPHI.FF.W.0016.180611T0333Z-180611T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1133 PM EDT SUN JUN 10 2018

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Northwestern Camden County in southern New Jersey...
  Northwestern Burlington County in southern New Jersey...
  South central Berks County in eastern Pennsylvania...
  Southern Montgomery County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...
  Central Philadelphia County in southeastern Pennsylvania...
  Northeastern Delaware County in southeastern Pennsylvania...

* Until 530 AM EDT Monday.

* At 1128 PM EDT, Doppler radar indicated heavy rain across the 
  warned area. One to two inches of rain have already fallen in some 
  areas over the last hour or two with additional rainfall amounts 
  of one to two inches in the next couple of hours. Flash flooding 
  is expected to begin shortly in the areas of heaviest rain 
  especially where training occurs.

* Some locations that could experience flooding include...
  Philadelphia, Norristown, Willingboro, Phoenixville, West Norriton,
  East Norriton, Lumberton, Burlington, Mount Holly, Riverside,
  Conshohocken, Palmyra, Royersford, Jenkintown, Narberth, Beverly,
  Rockledge, Honey Brook, Pemberton and Elverson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

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.

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 4008 7496 4006 7498 4005 7497 4007 7490
      4003 7465 3994 7468 4005 7593 4011 7594
      4014 7588 4022 7600 4026 7600

$$

Robertson

3 follow-up statements

553 
WGUS71 KPHI 110442
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1242 AM EDT MON JUN 11 2018

NJC005-007-PAC011-029-045-091-101-110930-
/O.CON.KPHI.FF.W.0016.000000T0000Z-180611T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-Burlington NJ-Berks PA-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
1242 AM EDT MON JUN 11 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 AM EDT FOR
NORTHWESTERN CAMDEN...NORTHWESTERN BURLINGTON...SOUTH CENTRAL
BERKS...SOUTHERN MONTGOMERY...NORTHEASTERN CHESTER...CENTRAL
PHILADELPHIA AND NORTHEASTERN DELAWARE COUNTIES...

At 1238 AM EDT, Doppler radar indicated heavy rain across the warned 
area. Two to four inches of rain have already fallen, and an 
additional inch of rain or so will fall. Flash flooding is already 
occurring. Water rescues are ongoing in the King of Prussia area 
along Interstate-76. Parts of Interstate-76 from Chesterbrook to 
Philadelphia are closed and underwater.

Some locations that could experience flooding include...
Philadelphia, Norristown, Willingboro, Phoenixville, West Norriton,
East Norriton, Lumberton, Burlington, Mount Holly, Riverside,
Conshohocken, Palmyra, Royersford, Jenkintown, Narberth, Beverly,
Rockledge, Honey Brook, Pemberton and Elverson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

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.

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

&&

LAT...LON 4008 7496 4006 7498 4005 7497 4007 7490
      4003 7465 3994 7468 4005 7593 4011 7594
      4014 7588 4022 7600 4026 7600

$$

MPS

430 
WGUS71 KPHI 110622
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
222 AM EDT MON JUN 11 2018

NJC005-007-PAC011-029-045-091-101-110930-
/O.CON.KPHI.FF.W.0016.000000T0000Z-180611T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-Burlington NJ-Berks PA-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
222 AM EDT MON JUN 11 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 AM EDT FOR
NORTHWESTERN CAMDEN...NORTHWESTERN BURLINGTON...SOUTH CENTRAL
BERKS...SOUTHERN MONTGOMERY...NORTHEASTERN CHESTER...CENTRAL
PHILADELPHIA AND NORTHEASTERN DELAWARE COUNTIES...

At 218 AM EDT, Doppler radar and automated rain gauges indicated two 
to four inches of rain, with as much as five inches of rain, has 
fallen over the warned area. The heaviest of the rain has moved 
south of the warned area, but flash flooding is ongoing with 
numerous road closures and water rescues. Some of the major roadways 
that are closed include I-76 in the King of Prussia area, U.S. 130 
in Pennsauken, and I-95 in Mayfair.

Some locations that could experience flooding include...
Philadelphia, Norristown, Willingboro, Phoenixville, West Norriton,
East Norriton, Lumberton, Burlington, Mount Holly, Riverside,
Conshohocken, Palmyra, Royersford, Jenkintown, Narberth, Beverly,
Rockledge, Honey Brook, Pemberton and Elverson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

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.

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

&&

LAT...LON 4008 7496 4006 7498 4005 7497 4007 7490
      4003 7465 3994 7468 4005 7593 4011 7594
      4014 7588 4022 7600 4026 7600

$$

MPS

911 
WGUS71 KPHI 110825
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
425 AM EDT MON JUN 11 2018

NJC005-007-PAC011-029-045-091-101-110834-
/O.CAN.KPHI.FF.W.0016.000000T0000Z-180611T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-Burlington NJ-Berks PA-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
425 AM EDT MON JUN 11 2018

...THE FLASH FLOOD WARNING FOR NORTHWESTERN CAMDEN...NORTHWESTERN
BURLINGTON...SOUTH CENTRAL BERKS...SOUTHERN MONTGOMERY...NORTHEASTERN
CHESTER...CENTRAL PHILADELPHIA AND NORTHEASTERN DELAWARE COUNTIES IS
CANCELLED...

The heavy rain has ended. Although the threat for flash flooding has 
ended, residual flooding continues. Roads will still be closed, and 
Areal Flood Warnings remain in effect. Please continue to heed any 
remaining road closures.

LAT...LON 4008 7496 4006 7498 4005 7497 4007 7490
      4003 7465 3994 7468 4005 7593 4011 7594
      4014 7588 4022 7600 4026 7600

$$

MPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 10, 8:29 PM EDT	Areal Flood Advisory	PHI	Berks, Chester, Montgomery	115 min
Jun 10, 9:52 PM EDT	Areal Flood Warning	PHI	Berks, Chester, Montgomery	18 hr
Jun 10, 10:38 PM EDT	Areal Flood Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	20 hr
Jun 11, 1:16 AM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Philadelphia	8 hr
Jun 11, 3:28 AM EDT	River Flood Warning	PHI	Chester	5 hr
Jun 11, 12:03 AM EDT	Areal Flood Warning	PHI	Ocean	7 hr
Jun 11, 12:53 AM EDT	Flash Flood Warning	PHI	Burlington, Ocean	4 hr
Jun 11, 2:15 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Gloucester, Ocean	7 hr
Jun 11, 3:16 AM EDT	Areal Flood Advisory	PHI	Cumberland, Salem	8 hr
Jun 11, 3:54 AM EDT	Areal Flood Advisory	PHI	Atlantic, Cape May, Cumberland, Gloucester	7 hr
Jun 11, 8:28 AM EDT	River Flood Warning	PHI	Burlington	58 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2018 Flash Flood Warnings in New Jersey, 2018 Every flash flood warning in 2018

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.