Alert archive / Delaware / Areal Flood Warnings in 2011

Areal Flood Warning 60, NWS Philadelphia/Mount Holly

August 28, 2011Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 28, 2011, 7:03 PM EDT for Sussex County, Delaware. It was in force for 22 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
Aug 28, 2011, 7:03 PM EDT (23:03 UTC)
Expired
Aug 29, 2011, 5:00 PM EDT
In force
22 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 25 km from the middle of the area, began a volume at 23:08 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

Wallops Is Stn, VA (KWAL), launched 12:00Z, 11.1 hours before the alert went out and 82 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-pSkew-T log-p diagram, Wallops Is Stn, VA at 12:00Z on 2011-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 11 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 12:00Z on 2011-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -77 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
11 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
915 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-77 m²/s²
0-3 km storm-relative helicity
143 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.

987 
WGUS41 KPHI 282303
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
703 PM EDT SUN AUG 28 2011

DEC005-290700-
/O.NEW.KPHI.FA.W.0060.110828T2303Z-110829T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
703 PM EDT SUN AUG 28 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLOOD WARNING FOR SMALL STREAMS IN...
  WESTERN SUSSEX COUNTY IN SOUTHERN DELAWARE...

* UNTIL 300 AM EDT MONDAY

* AT 659 PM EDT...THE RIVER GAGE IN BRIDGEVILLE ALONG THE NANTICOKE 
REMAINED ABOVE FLOOD STAGE. ALTHOUGH WATER LEVELS ARE EXPECTED TO 
CREST THIS EVENING, FLOODING WILL CONTINUE THROUGH THE OVERNIGHT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED ACT QUICKLY. MOVE UP TO
HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO
FLOODING WHEN WATER BEGINS RISING.

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.

&&

LAT...LON 3846 7570 3847 7571 3855 7572 3869 7571
      3883 7573 3884 7555 3887 7552 3888 7546
      3845 7541

$$

KRUZDLO
2 follow-up statements
676 
WGUS41 KPHI 290636
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
236 AM EDT MON AUG 29 2011

DEC005-291500-
/O.EXT.KPHI.FA.W.0060.000000T0000Z-110829T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
236 AM EDT MON AUG 29 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLOOD WARNING FOR SMALL STREAMS IN...
  WESTERN SUSSEX COUNTY IN SOUTHERN DELAWARE...

* UNTIL 1100 AM EDT

* AT 234 AM EDT...THE RIVER GAGE IN BRIDGEVILLE ALONG THE NANTICOKE 
REMAINED ABOVE FLOOD STAGE. WATER LEVELS HAVE CRESTED, BUT FLOODING 
WILL CONTINUE THROUGH THE MORNING.

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.

&&

LAT...LON 3846 7570 3847 7571 3855 7572 3869 7571
      3883 7573 3884 7555 3887 7552 3888 7546
      3845 7541

$$

KRUZDLO
512 
WGUS41 KPHI 291414
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1014 AM EDT MON AUG 29 2011

DEC005-292100-
/O.EXT.KPHI.FA.W.0060.000000T0000Z-110829T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
1014 AM EDT MON AUG 29 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLOOD WARNING FOR SMALL STREAMS IN...
  WESTERN SUSSEX COUNTY IN SOUTHERN DELAWARE...

* UNTIL 500 PM EDT MONDAY

* AT 1012 AM EDT...THE RIVER GAGE IN BRIDGEVILLE ALONG THE NANTICOKE
REMAINED ABOVE FLOOD STAGE. WATER LEVELS HAVE CRESTED, BUT MINOR 
FLOODING WILL CONTINUE THROUGH AT LEAST PART OF THE AFTERNOON HOURS.

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.

&&

LAT...LON 3846 7570 3847 7571 3855 7572 3869 7571
      3883 7573 3884 7555 3887 7552 3888 7546
      3845 7541

$$

JJM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 27, 8:28 PM EDTFlash Flood WarningPHIKent, New Castle, Sussex12 hr
Aug 27, 8:33 PM EDTTornado WarningPHIKent, Sussex27 min
Aug 27, 8:49 PM EDTTornado WarningPHIKent26 min
Aug 27, 9:46 PM EDTTornado WarningPHINew Castle29 min
Aug 27, 10:14 PM EDTTornado WarningPHINew Castle31 min
Aug 27, 11:37 PM EDTFlash Flood WarningPHINew Castle12 hr
Aug 28, 7:07 AM EDTAreal Flood WarningPHIKent, Sussex12 hr
Aug 28, 8:09 AM EDTAreal Flood WarningPHINew Castle12 hr
Aug 28, 11:07 AM EDTAreal Flood WarningPHINew Castle18 hr

Nearby

Areal Flood Warnings in Delaware, 2011Every areal flood warning in 2011

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.