Alert archive / Maryland / Flash Flood Warnings in 2009

Flash Flood Warning 60, NWS Philadelphia/Mount Holly

August 28, 20094 counties in Maryland

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 28, 2009, 2:53 PM EDT for 4 counties in Maryland. It was in force for 6 hr. 1 report 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
Aug 28, 2009, 2:53 PM EDT (18:53 UTC)
Expired
Aug 28, 2009, 9:15 PM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Caroline County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 64 km from the middle of the area, began a volume at 18:54 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

TimeReportWhereRemark
Aug 28, 3:14 PM EDTFLASH FLOODRidgely, MDROAD CLOSED BETWEEN RIDGELY AND DENTON.

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 12:00Z, 6.9 hours before the alert went out and 110 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, Washington/Dulle, VA at 12:00Z on 2009-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 787 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, Washington/Dulle, VA at 12:00Z on 2009-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 69 square meters per square second.193958Sfc1 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
787 J/kg
Mixed-layer CIN
-74 J/kg
Mixed-layer LCL
613 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
69 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 281853
FFWPHI
MDC011-029-035-041-282245-
/O.NEW.KPHI.FF.W.0060.090828T1853Z-090828T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
253 PM EDT FRI AUG 28 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN CAROLINE COUNTY IN EASTERN MARYLAND...
  NORTH CENTRAL TALBOT COUNTY IN EASTERN MARYLAND...
  EASTERN KENT COUNTY IN NORTHEAST MARYLAND...
  QUEEN ANNES COUNTY IN NORTHEAST MARYLAND...
  THIS INCLUDES THE CITY OF CENTERVILLE...

* UNTIL 645 PM EDT

* AT 244 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  HEAVY RAIN ACROSS THE EASTERN SHORE. AN ADDITIONAL ONE TO TWO      
  INCHES OF RAIN IS LIKELY OVER THE NEXT COUPLE HOURS ACROSS         
  PORTIONS OF THE WARNED AREA. THIS IS IN ADDITION TO THE ONE TO     
  TWO INCHES THAT ALREADY FELL IN SPOTS. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  GRASONVILLE...STARKEY CORNER...STARR...SASSAFRAS...OVERTON...OLD
  TOWN...MORGNEC...MASSEY...KENNEDYVILLE...JUMPTOWN...HOPE...
  CRUMPTON...CARVILLE...OAKLAND...SUDLERSVILLE...MILLINGTON...
  GREENSBORO...GOLDSBORO...CHURCH HILL...CHESTERTOWN AND CENTREVILLE

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. 

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. 

&&

LAT...LON 3899 7627 3898 7620 3900 7618 3903 7624
      3907 7622 3937 7594 3938 7577 3899 7574
      3885 7621 3893 7621 3894 7624 3890 7624

$$

KRUZDLO
1 follow-up statement
000 
WGUS51 KPHI 282239
FFWPHI
MDC011-029-035-041-290115-
/O.EXT.KPHI.FF.W.0060.000000T0000Z-090829T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
639 PM EDT FRI AUG 28 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  NORTHERN CAROLINE COUNTY IN EASTERN MARYLAND...
  NORTH CENTRAL TALBOT COUNTY IN EASTERN MARYLAND...
  EASTERN KENT COUNTY IN NORTHEAST MARYLAND...
  QUEEN ANNES COUNTY IN NORTHEAST MARYLAND...
  THIS INCLUDES THE CITY OF CENTERVILLE...

* UNTIL 915 PM EDT

* AT 636 PM EDT...MORE HEAVY RAIN WAS MOVING NORTH INTO THE WARNED   
  AREA. ANOTHER ONE TO TWO INCHES IS LIKELY IN SPOTS. THE FLASH      
  FLOOD WARNING HAS BEEN EXTENDED.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO STARKEY
  CORNER...SASSAFRAS...OLD TOWN...MORGNEC...MASSEY...KENNEDYVILLE...
  HOPE...CRUMPTON...CARVILLE...SUDLERSVILLE...MILLINGTON...CHURCH
  HILL...CHESTERTOWN AND CENTREVILLE

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. 

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. 

&&

LAT...LON 3899 7627 3898 7620 3900 7618 3903 7624
      3907 7622 3937 7594 3938 7577 3899 7574
      3885 7621 3893 7621 3894 7624 3890 7624

$$

KRUZDLO

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 1:40 AM EDTFlash Flood WarningPHICecil5 hr
Aug 28, 2:13 PM EDTFlash Flood WarningPHICecil2 hr
Aug 28, 2:52 PM EDTFlash Flood WatchPHICecil14 hr
Aug 28, 3:21 PM EDTFlash Flood WarningPHICaroline, Talbot6 hr
Aug 28, 6:49 PM EDTAreal Flood AdvisoryPHICaroline, Talbot5 hr

Nearby

Flash Flood Warnings in Maryland, 2009Every flash flood warning in 2009

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.