Alert archive / Maryland / Flash Flood Warnings in 2009

Flash Flood Warning 59, NWS Philadelphia/Mount Holly

August 28, 2009Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 28, 2009, 2:13 PM EDT for Cecil County, Maryland. It was in force for 2 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, 2:13 PM EDT (18:13 UTC)
Expired
Aug 28, 2009, 4:30 PM EDT
In force
2 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Cecil County, MD

The radar

The Dover AFB radar (KDOX), 86 km from the middle of the area, began a volume at 18:15 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, 2:55 PM EDTFLASH FLOODCayots, MDOLD TELEGRAPH ROAD CLOSED JUST EAST OF CAYOTS.

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, 6.2 hours before the alert went out and 138 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 281813
FFWPHI
MDC015-282030-
/O.NEW.KPHI.FF.W.0059.090828T1813Z-090828T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN CECIL COUNTY IN NORTHEAST MARYLAND...
  THIS INCLUDES THE CITY OF ELKTON...

* UNTIL 430 PM EDT

* AT 202 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  HEAVY RAIN ACROSS THE SOUTHERN PORTION OF CECIL COUNTY. 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 TWO TO ALMOST FOUR INCHES THAT FELL IN SPOTS       
  EARLIER THIS MORNING. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO HOLLYWOOD
  BEACH...CAYOTS...BRANTWOOD...NORTH EAST AND CHARLESTOWN

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 3967 7579 3939 7577 3938 7585 3937 7584
      3938 7604 3941 7605 3942 7602 3945 7600
      3946 7602 3953 7599 3955 7603 3954 7607
      3957 7610

$$

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, 2:52 PM EDTFlash Flood WatchPHICecil14 hr
Aug 28, 2:53 PM EDTFlash Flood WarningPHICaroline, Kent, Queen Anne's, Talbot6 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.