Alert archive / Maryland / Flash Flood Warnings in 2009

Flash Flood Warning 50, NWS Philadelphia/Mount Holly

August 22, 2009Caroline County, Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 22, 2009, 3:53 PM EDT for Caroline County, Talbot County, 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 22, 2009, 3:53 PM EDT (19:53 UTC)
Expired
Aug 22, 2009, 10:15 PM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Caroline County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 61 km from the middle of the area, began a volume at 19:55 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 22, 5:45 PM EDTFLASH FLOODEaston, MDMANY ROADWAYS FLOOD THROUGHOUT COUNTY

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, 7.9 hours before the alert went out and 111 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 2009-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 621 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 2009-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -26 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
621 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
539 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
-26 m²/s²
0-3 km storm-relative helicity
5 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.

000 
WGUS51 KPHI 221953
FFWPHI
MDC011-041-222345-
/O.NEW.KPHI.FF.W.0050.090822T1953Z-090822T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
353 PM EDT SAT AUG 22 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHWESTERN CAROLINE COUNTY IN EASTERN MARYLAND...
  TALBOT COUNTY IN EASTERN MARYLAND...
  THIS INCLUDES THE CITY OF EASTON...

* UNTIL 745 PM EDT

* AT 347 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO TALBOT...
  SKIPTON...MATTHEWS...GRIFFIN...CORDOVA AND COPPERVILLE

THIS FLASH FLOOD WARNING IS SOUTH OF THE TOWN OF RIDGELY BUT WE ARE
MONITORING THE AREA IN THE EVENT MORE HEAVY SHOWERS MOVE CLOSE TO
RIDGELY WHERE OVER NINE INCHES FELL EARLIER THIS MORNING. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 3859 7607 3866 7617 3866 7621 3873 7625
      3872 7631 3868 7635 3881 7632 3886 7626
      3887 7625 3884 7625 3883 7621 3888 7615
      3887 7611 3893 7611 3891 7601 3893 7584
      3869 7586 3867 7595 3858 7600

$$

EBERWINE
1 follow-up statement
000 
WGUS51 KPHI 222329
FFWPHI
MDC011-041-230215-
/O.EXT.KPHI.FF.W.0050.000000T0000Z-090823T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
729 PM EDT SAT AUG 22 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  SOUTHWESTERN CAROLINE COUNTY IN EASTERN MARYLAND...
  TALBOT COUNTY IN EASTERN MARYLAND...
  THIS INCLUDES THE CITY OF EASTON...

* UNTIL 1015 PM EDT

* AT 725 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A LARGE AREA OF HEAVY SHOWERS AND THUNDERSTORMS.
  AN ADDITIONAL THREE INCHES ARE POSSIBLE BEFORE MIDNIGHT. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO TALBOT...
  SKIPTON...MATTHEWS...HARMONY...GRIFFIN...CORDOVA...COPPERVILLE AND
  ST. MICHAELS

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH 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.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 3859 7607 3866 7617 3866 7621 3873 7625
      3872 7631 3868 7635 3881 7632 3886 7626
      3887 7625 3884 7625 3883 7621 3888 7615
      3887 7611 3893 7611 3891 7601 3893 7584
      3869 7586 3867 7595 3858 7600

$$

EBERWINE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 10:14 PM EDTAreal Flood AdvisoryPHICecil, Kent3 hr
Aug 21, 11:49 PM EDTAreal Flood AdvisoryPHICaroline, Queen Anne's, Talbot116 min
Aug 22, 12:45 AM EDTAreal Flood WarningPHICaroline17 hr
Aug 22, 1:28 AM EDTFlash Flood WarningPHICaroline, Queen Anne's4 hr
Aug 22, 2:19 AM EDTAreal Flood AdvisoryPHICaroline, Queen Anne's, Talbot6 hr
Aug 22, 4:26 AM EDTAreal Flood AdvisoryPHICaroline6 hr
Aug 22, 5:42 AM EDTAreal Flood AdvisoryPHICaroline, Queen Anne's3 hr
Aug 22, 8:12 AM EDTAreal Flood AdvisoryPHICaroline, Kent, Queen Anne's, Talbot3 hr
Aug 22, 4:46 PM EDTFlash Flood WarningPHICaroline5 hr
Aug 22, 5:40 PM EDTAreal Flood WarningPHICaroline14 hr
Aug 22, 6:02 PM EDTFlash Flood WarningPHICecil, Kent, Queen Anne's4 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.