Alert archive / Pennsylvania / Flash Flood Warnings in 2016

Flash Flood Warning 6, NWS Philadelphia/Mount Holly

May 30, 2016Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at May 30, 2016, 4:17 AM EDT for Philadelphia County, Pennsylvania. It was in force for 118 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 30, 2016, 4:17 AM EDT (08:17 UTC)
Expired: May 30, 2016, 6:15 AM EDT
In force: 118 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 59 km from the middle of the area, began a volume at 08:18 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, 8.3 hours before the alert went out and 211 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: 4 J/kg
Mixed-layer CIN: -200 J/kg
Mixed-layer LCL: 666 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 76 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

939 
WGUS51 KPHI 300817
FFWPHI
PAC101-301015-
/O.NEW.KPHI.FF.W.0006.160530T0817Z-160530T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
417 AM EDT MON MAY 30 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL PHILADELPHIA COUNTY IN SOUTHEASTERN PENNSYLVANIA...

* UNTIL 615 AM EDT

* AT 414 AM EDT...DOPPLER RADAR INDICATED HEAVY RAIN ACROSS THE
  WARNED AREA. UP TO TWO INCHES OF RAIN HAVE ALREADY FALLEN. FLASH
  FLOODING IS ALREADY OCCURRING.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  PHILADELPHIA.

THE FRANKFORD CREEK HAS SHARPLY RISEN INTO FLOOD AFTER 1 TO 2 INCHES
OF RAIN FELL IN SHORT TIME EARLY THIS MORNING. IT MAY CREST AT
MODERATE FLOOD LEVELS BEFORE QUICKLY RECEDING BY 6 AM. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO HIGHER GROUND NOW. ACT QUICKLY TO PROTECT YOUR LIFE.

DO NOT ENTER OR CROSS FLOWING WATER OR WATER OF UNKNOWN DEPTH. 

&&

LAT...LON 4004 7506 3999 7508 4000 7516 4003 7512

$$

DRAG

1 follow-up statement

489 
WGUS71 KPHI 300846
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
446 AM EDT MON MAY 30 2016

PAC101-301015-
/O.CON.KPHI.FF.W.0006.000000T0000Z-160530T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PHILADELPHIA PA-
446 AM EDT MON MAY 30 2016

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 AM EDT FOR
CENTRAL PHILADELPHIA COUNTY...

AT 442 AM EDT...DOPPLER RADAR INDICATED THE HEAVY RAINS HAVE
ENDED ACROSS THE WARNED AREA OF PHILADELPHIA WITH ONLY MAYBE A
QUARTER INCH AT MOST OF NEW RAINFALL UPCOMING PRIOR TO 530 AM. 

THE FRANKFORD CREEK JUST AS QUICKLY RECEDED WITHIN ITS BANKS. 
HOWEVER, THERE MAY STILL BE SOME RESIDUAL FLOODING NEAR THE
FRANKFORD CREEK AND IN CENTRAL PHILADELPHIA COUNTY AND SO THE
WARNING CONTINUES THROUGH ITS EXPIRATION.  


SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
CENTRAL PHILADELPHIA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT ENTER OR CROSS FLOWING WATER OR WATER OF UNKNOWN DEPTH. 

&&

LAT...LON 4004 7506 3999 7508 4000 7516 4003 7512

$$
DRAG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 29, 10:39 PM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery, Philadelphia	6 hr
May 29, 11:27 PM EDT	Areal Flood Advisory	PHI	Bucks	8 hr
May 30, 1:56 AM EDT	Areal Flood Advisory	PHI	Carbon, Lehigh, Monroe, Northampton	4 hr
May 30, 4:33 AM EDT	Flash Flood Warning	PHI	Philadelphia	117 min
May 30, 5:52 PM EDT	Special Weather Statement	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	83 min

Nearby

Flash Flood Warnings in Pennsylvania, 2016 Every flash flood warning in 2016

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.