Alert archive / Maryland / Flash Flood Warnings in 2011
Flash Flood Warning 30, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 15, 2011, 1:38 PM EDT for Kent County, New Castle County, Delaware; Cecil County, Kent County, Queen Anne's County, Maryland. 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
- Aug 15, 2011, 1:38 PM EDT (17:38 UTC)
- Expired
- Aug 15, 2011, 5:14 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Kent County, DE, New Castle County, DE, Cecil County, MD, Kent County, MD, Queen Anne's County, MD
The radar
The Dover AFB radar (KDOX), 60 km from the middle of the area, began a volume at 17:38 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
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 5.6 hours before the alert went out and 32 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.
- Mixed-layer CAPE
- 460 J/kg
- Mixed-layer CIN
- -20 J/kg
- Mixed-layer LCL
- 689 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 7 m²/s²
- 0-3 km storm-relative helicity
- 31 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted, in the capitals the NWS used until 2016.
941
WGUS51 KPHI 151738
FFWPHI
DEC001-003-MDC015-029-035-152130-
/O.NEW.KPHI.FF.W.0030.110815T1738Z-110815T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
138 PM EDT MON AUG 15 2011
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* FLASH FLOOD WARNING FOR...
KENT COUNTY...
CECIL COUNTY...
QUEEN ANNE'S COUNTY...
NEW CASTLE COUNTY...
KENT COUNTY DELAWARE...
* UNTIL 530 PM EDT...
* AT 130 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SHOWERS AND THUNDERSTORMS EXTENDING FROM CECIL COUNTY
SOUTH INTO QUEEN ANNE/S COUNTY. THIS LINE WAS MOVING ONLY VERY
SLOWLY TO THE EAST AT 10 MPH. SOME VERY HEAVY RAIN IN THIS LINE
HAS THE POTENTIAL TO DROP OVER ONE INCH PER HOUR. ANOTHER AREA OF
RAIN NEAR THE NEW CASTLE AND KENT COUNTY LINE IN DELAWARE WAS ALSO
MOVING SLOWLY EAST AT 10 MPH. GIVEN THE VERY WET CONDITIONS
ACROSS THE AREA FROM RAIN ON BOTH SATURDAY AND SUNDAY, FLASH
FLOODING CAN BE EXPECTED WHEREVER THE HEAVIEST RAIN HAPPENS TO FALL.
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. MANY FLOODING DEATHS OCCUR IN CARS!
PLEASE REPORT FLOODING...HAIL OR WIND DAMAGE TO THE NATIONAL WEATHER
SERVICE BY CALLING TOLL FREE...1-877-633-6772.
&&
LAT...LON 3905 7631 3900 7618 3918 7628 3951 7599
3972 7624 3973 7578 3982 7546 3981 7544
3962 7560 3946 7558 3924 7538 3895 7530
3883 7572 3914 7579 3892 7595 3894 7610
3881 7611 3894 7624 3891 7632 3891 7633
$$
FORECASTER:JJM/GH1 follow-up statement
742
WGUS71 KPHI 152114
FFSPHI
FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
514 PM EDT MON AUG 15 2011
DEC001-003-MDC015-029-035-152125-
/O.CAN.KPHI.FF.W.0030.000000T0000Z-110815T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KENT DE-CECIL MD-KENT MD-QUEEN ANNE'S MD-NEW CASTLE DE-
514 PM EDT MON AUG 15 2011
...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR NEW CASTLE...QUEEN
ANNE'S...KENT...CECIL AND KENT COUNTIES...
THE WATERS FROM THE EARLIER HEAVY RAINS ARE RECEDING AND FLOOD WATERS
NO LONGER POSE A THREAT TO LIFE OR PROPERTY. THEREFORE...THE FLASH
FLOOD WARNING HAS BEEN CANCELLED.
LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO DOVER...
MIDDLETOWN...NEWARK...WILMINGTON...ELKTON AND CENTERVILLE.
LAT...LON 3905 7631 3900 7618 3918 7628 3951 7599
3972 7624 3973 7578 3982 7546 3981 7544
3962 7560 3946 7558 3924 7538 3895 7530
3883 7572 3914 7579 3892 7595 3894 7610
3881 7611 3894 7624 3891 7632 3891 7633
$$
FORECASTER:JJMThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 15, 12:56 AM EDT | Special Weather Statement | PHI | New Castle | 64 min |
| Aug 15, 10:58 AM EDT | Special Weather Statement | PHI | Kent | 62 min |
| Aug 15, 1:05 PM EDT | Areal Flood Advisory | PHI | New Castle | 4 hr |
| Aug 15, 2:47 PM EDT | Special Weather Statement | PHI | Kent | 58 min |
| Aug 15, 3:18 PM EDT | Severe Thunderstorm Warning | PHI | Kent, Sussex | 57 min |
| Aug 15, 3:25 PM EDT | Special Weather Statement | PHI | Kent, Sussex | 3 hr |
| Aug 15, 12:05 AM EDT | Special Weather Statement | PHI | Queen Anne's | 40 min |
Nearby
Flash Flood Warnings in Maryland, 2011Flash Flood Warnings in Delaware, 2011Every flash 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.