Alert archive / Delaware / Areal Flood Warnings in 2012

Areal Flood Warning 38, NWS Philadelphia/Mount Holly

December 21, 2012New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood warning at Dec 21, 2012, 5:33 AM EST for New Castle County, Delaware. It was in force for 4 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: Dec 21, 2012, 5:33 AM EST (10:33 UTC)
Expired: Dec 21, 2012, 9:30 AM EST
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County New Castle County, DE

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 10.6 hours before the alert went out and 171 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 0 m above ground
0-6 km bulk shear: 72 kt
0-1 km storm-relative helicity: 607 m²/s²
0-3 km storm-relative helicity: 893 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

088 
WGUS41 KPHI 211033
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
533 AM EST FRI DEC 21 2012

DEC003-211430-
/O.NEW.KPHI.FA.W.0038.121221T1033Z-121221T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE DE-
533 AM EST FRI DEC 21 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLOOD WARNING FOR URBAN AREAS AND SMALL STREAMS IN...
  NEW CASTLE COUNTY IN NORTHERN DELAWARE...

* UNTIL 930 AM EST

* AT 531 AM EST MODERATE TO HEAVY RAINS ARE FALLING ACROSS THE AREA. 
THEY WILL CONTINUE FOR ANOTHER FEW HOURS. 

* FLOODING WILL AFFECT THE CHRISTINA RIVER AND OTHER NEARBY STREAMS  
  AND CREEKS. 

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.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

A FLOOD WARNING MEANS FLOODING IS OCCURRING OR IS IMMINENT. MOST
FLOOD RELATED DEATHS OCCUR IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS
WATER COVERED BRIDGES...DIPS...OR LOW WATER CROSSINGS. NEVER TRY TO
CROSS A FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING
WATER MOVE UP TO HIGHER GROUND.

&&

LAT...LON 3983 7565 3983 7547 3979 7541 3962 7560
      3960 7560 3964 7557 3959 7556 3958 7558
      3952 7556 3946 7559 3942 7553 3936 7551
      3935 7556 3931 7559 3930 7576 3972 7579

$$

PO

1 follow-up statement

931 
WGUS81 KPHI 211428
FLSPHI

FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
928 AM EST FRI DEC 21 2012

DEC003-211436-
/O.EXP.KPHI.FA.W.0038.000000T0000Z-121221T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE DE-
928 AM EST FRI DEC 21 2012

...THE FLOOD WARNING WILL EXPIRE AT 930 AM EST FOR URBAN AREAS AND
SMALL STREAMS IN NEW CASTLE COUNTY...

ALTHOUGH THIS FLOOD WARNING ISSUED FOR A WIDE AREA ACROSS THE COUNTY 
WILL EXPIRE, INDIVIDUAL RIVER/CREEK FLOOD WARNINGS REMAIN IN PLACE 
FOR THE CHRISTINA, WHITE CLAY, AND RED CLAY.

LAT...LON 3983 7565 3983 7547 3979 7541 3962 7560
      3960 7560 3964 7557 3959 7556 3958 7558
      3952 7556 3946 7559 3942 7553 3936 7551
      3935 7556 3931 7559 3930 7576 3972 7579

$$

KRUZDLO

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 20, 9:11 PM EST	Wind Advisory	PHI	Kent, New Castle, Sussex	12 hr
Dec 21, 12:27 AM EST	Coastal Flood Warning	PHI	Kent, New Castle	11 hr
Dec 21, 7:10 AM EST	River Flood Warning	PHI	New Castle	5 hr
Dec 21, 7:56 AM EST	River Flood Warning	PHI	New Castle	4 hr
Dec 21, 8:49 AM EST	River Flood Warning	PHI	New Castle	3 hr
Dec 21, 3:16 PM EST	Wind Advisory	PHI	Kent, New Castle, Sussex	27 hr

Nearby

Areal Flood Warnings in Delaware, 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.