Alert archive / Pennsylvania / Areal Flood Warnings in 2012

Areal Flood Warning 4, NWS Philadelphia/Mount Holly

May 16, 2012Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at May 16, 2012, 2:37 AM EDT for Philadelphia County, Pennsylvania. It was in force for 3 hr. 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 16, 2012, 2:37 AM EDT (06:37 UTC)
Expired: May 16, 2012, 5:40 AM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 65 km from the middle of the area, began a volume at 06:37 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, 6.6 hours before the alert went out and 218 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: 254 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 438 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 91 m²/s²
0-3 km storm-relative helicity: 117 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

726 
WGUS41 KPHI 160637
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
237 AM EDT WED MAY 16 2012

PAC101-161030-
/O.NEW.KPHI.FA.W.0004.120516T0637Z-120516T1030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PHILADELPHIA PA-
237 AM EDT WED MAY 16 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLOOD WARNING FOR...
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 630 AM EDT

* AT 236 AM EDT...THE FRANKFORD CREEK WAS ABOVE FLOOD STAGE. WHILE 
THE HEAVIEST RAIN IS EXITING THE AREA...RUNOFF FROM THE HEAVY RAIN 
COULD RESULT IN ADDITIONAL FLOODING ACROSS PHILADELPHIA THROUGH THE 
EARLY MORNING HOURS.

A FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR HAS BEEN REPORTED.
STREAM RISES WILL BE SLOW AND FLASH FLOODING IS NOT EXPECTED.
HOWEVER...ALL INTERESTED PARTIES SHOULD TAKE NECESSARY PRECAUTIONS
IMMEDIATELY.

LAT...LON 3988 7523 3992 7525 3994 7524 3996 7525
      3998 7528 4000 7522 4002 7521 4006 7514
      4005 7510 4008 7508 4014 7501 4005 7499

$$

HAYES

1 follow-up statement

484 
WGUS81 KPHI 160940
FLSPHI

FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
540 AM EDT WED MAY 16 2012

PAC101-160950-
/O.CAN.KPHI.FA.W.0004.000000T0000Z-120516T1030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PHILADELPHIA PA-
540 AM EDT WED MAY 16 2012

...THE FLOOD WARNING HAS BEEN CANCELLED FOR PHILADELPHIA COUNTY...

CREEKS AND STREAM CONTINUE TO FALL...AND FLOODING IS NO LONGER 
EXPECTED. 

LAT...LON 3988 7523 3992 7525 3994 7524 3996 7525
      3998 7528 4000 7522 4002 7521 4006 7514
      4005 7510 4008 7508 4014 7501 4005 7499

$$

HAYES

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 8:19 PM EDT	Special Weather Statement	PHI	Bucks	86 min
May 15, 8:46 PM EDT	Areal Flood Warning	PHI	Northampton	76 min
May 15, 9:00 PM EDT	Special Weather Statement	PHI	Berks	90 min
May 15, 9:49 PM EDT	Special Weather Statement	PHI	Berks, Bucks, Chester, Lehigh, Montgomery	86 min
May 15, 10:45 PM EDT	Areal Flood Advisory	PHI	Chester	57 min
May 15, 11:05 PM EDT	Special Weather Statement	PHI	Bucks, Chester, Delaware, Montgomery	55 min
May 15, 11:24 PM EDT	Areal Flood Advisory	PHI	Chester, Montgomery	116 min
May 15, 11:38 PM EDT	Areal Flood Warning	PHI	Chester, Montgomery	4 hr
May 16, 12:12 AM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery	3 hr
May 16, 12:20 AM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	55 min
May 16, 12:34 AM EDT	Flash Flood Warning	PHI	Chester, Delaware, Montgomery	4 hr
May 16, 4:27 AM EDT	Areal Flood Warning	PHI	Delaware	3 hr

Nearby

Areal Flood Warnings in Pennsylvania, 2012 Every areal flood warning in 2012

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.