Alert archive / Pennsylvania / Flash Flood Warnings in 2013

Flash Flood Warning 23, NWS Philadelphia/Mount Holly

June 30, 2013Chester County, Pennsylvania; Cecil County, Maryland; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 30, 2013, 11:45 AM EDT for Chester County, Pennsylvania; Cecil County, Maryland; New Castle County, Delaware. It was in force for 5 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: Jun 30, 2013, 11:45 AM EDT (15:45 UTC)
Expired: Jun 30, 2013, 4:26 PM EDT
In force: 5 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties New Castle County, DE, Cecil County, MD, Chester County, PA

The radar

The Dover AFB radar (KDOX), 98 km from the middle of the area, began a volume at 15:46 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

Time	Report	Where	Remark
Jun 30, 2:15 PM EDT	FLASH FLOOD	New Castle, DE	SEVERAL VEHICLES TRAPPED IN HIGH WATER IN NEW CASTLE.

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, 3.8 hours before the alert went out and 167 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 97 J/kg
Mixed-layer CIN: -123 J/kg
Mixed-layer LCL: 1167 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 36 m²/s²
0-3 km storm-relative helicity: 74 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.

632 
WGUS51 KPHI 301545
FFWPHI
DEC003-MDC015-PAC029-301745-
/O.NEW.KPHI.FF.W.0023.130630T1545Z-130630T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1145 AM EDT SUN JUN 30 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN NEW CASTLE COUNTY...
  CECIL COUNTY...
  SOUTHERN CHESTER COUNTY...

* UNTIL 145 PM EDT...

* AT 1138 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  POTENTIAL FOR FLASH FLOODING FROM GROUPS OF THUNDERSTORMS OVER
  CECIL...NORTHERN NEW CASTLE   AND SOUTHERN CHESTER COUNTIES.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WILMINGTON
  AND NEWARK.

THE PRIMARY THREAT AREA IS THE REGION HIT BY FLOODING LAST FRIDAY
IN FAR NORTHWESTERN NEW CASTLE COUNTY DELAWARE AND THE NORTHERN
BORDER OF CECIL COUNTY.  THESE STORMS WILL SOON MOVE INTO SOUTHERN
CHESTER COUNTY PENNSYLVANIA.

THUNDERSTORMS MAY END FOR A TIME ABOUT AN HOUR AFTER THEY BEGIN BUT 
COULD RESUME DURING MID AFTERNOON. 

ADDITIONAL RAINFALL AMOUNTS OF 1 TO 2 INCHES IN 1 HOUR ARE EXPECTED 
IN PORTIONS OF THE WARNING AREA. 

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. NEVER ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR IN AN
AUTOMOBILE. TURN AROUND DON'T DROWN!

DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. ONLY A FEW INCHES OF
RAPIDLY FLOWING WATER CAN QUICKLY CARRY AWAY YOUR VEHICLE.

&&

LAT...LON 3974 7609 3986 7560 3984 7558 3984 7553
      3980 7543 3965 7555 3964 7557 3963 7557
      3964 7558 3963 7560 3960 7560 3953 7565
      3946 7596 3960 7606

$$

FORECASTER:  DRAG

5 follow-up statements

891 
WGUS71 KPHI 301643
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1243 PM EDT SUN JUN 30 2013

DEC003-MDC015-PAC029-301745-
/O.CON.KPHI.FF.W.0023.000000T0000Z-130630T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE DE-CECIL MD-CHESTER PA-
1243 PM EDT SUN JUN 30 2013

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 145 PM EDT FOR
SOUTHERN CHESTER...CECIL AND NORTHERN NEW CASTLE COUNTIES...

AT 1234 PM EDT...DOPPLER RADAR INDICATE NEW HEAVY SHOWERS AND 
THUNDERSTORMS DEVELOPING IN OR APPROACHING THE WARNING AREA.

THE HEAVIEST RAIN SO FAR OCCURRED IN EASTERN CECIL COUNTY AND 
NORTHERN NEW CASTLE COUNTY.

HEAVY RAIN HAS MISSED CHESTER COUNTY BUT THE WARNING CONTINUES IN 
EXPECTATION OF RENEWED DEVELOPMENT IN PORTIONS OF THE WARNING AREA 
BETWEEN NOW AND 145 PM. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF A COUPLE 
OF SMALL CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND 
UNDERPASSES AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.


&&

LAT...LON 3974 7609 3986 7560 3984 7558 3984 7553
      3980 7543 3965 7555 3964 7557 3963 7557
      3964 7558 3963 7560 3960 7560 3953 7565
      3946 7596 3960 7606

$$

FORECASTER:  DRAG

852 
WGUS51 KPHI 301721
FFWPHI
DEC003-MDC015-PAC029-302145-
/O.EXT.KPHI.FF.W.0023.000000T0000Z-130630T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
121 PM EDT SUN JUN 30 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  NORTHERN NEW CASTLE COUNTY...
  CECIL COUNTY...
  SOUTHERN CHESTER COUNTY...

* UNTIL 545 PM EDT...

* AT 119 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  MORE THUNDERSTORMS WITH HEAVY RAIN MOVING INTO THE WARNING 
  AREA WITH EASTERN CECIL COUNTY AND NEW CASTLE COUNTY MOST
  VULNERABLE TO ADDITIONAL FLASH FLOODING. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WILMINGTON
  AND NEWARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS OCCURRING OR IS IMMINENT. MOST FLOOD RELATED DEATHS OCCUR
IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED BRIDGES...
DIPS...OR LOW WATER CROSSINGS. TURN AROUND...DON'T DROWN! NEVER TRY
TO CROSS A FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO ESCAPE
RISING WATER MOVE UP TO HIGHER GROUND.

&&

LAT...LON 3974 7609 3986 7560 3984 7558 3984 7553
      3980 7543 3965 7555 3964 7557 3963 7557
      3964 7558 3963 7560 3960 7560 3953 7565
      3946 7596 3960 7606

$$

TFG

206 
WGUS71 KPHI 301829
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
229 PM EDT SUN JUN 30 2013

PAC029-301835-
/O.CAN.KPHI.FF.W.0023.000000T0000Z-130630T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CHESTER PA-
229 PM EDT SUN JUN 30 2013

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHERN CHESTER
COUNTY...

THE HEAVIEST RAIN HAS REMAINED SOUTH OF THE COUNTY.
 
LAT...LON 3972 7581 3972 7578 3976 7575 3983 7565
      3984 7552 3980 7543 3968 7553 3969 7553
      3966 7554 3963 7560 3960 7560 3953 7565
      3946 7596 3960 7601

$$

DEC003-MDC015-302145-
/O.CON.KPHI.FF.W.0023.000000T0000Z-130630T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE DE-CECIL MD-
229 PM EDT SUN JUN 30 2013

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM EDT FOR
EASTERN CECIL AND NORTHERN NEW CASTLE COUNTIES...

AT 219 PM EDT...DOPPLER RADAR STORM TOTAL ESTIMATES REACHED AROUND 
THREE INCHES FROM HOLLYWOOD BEACH NORTHEASTWARD THROUGH ELKTON, GLASGOW,
BEAR AND NEW CASTLE. SOME SHOWERS WITH HEAVY RAIN ARE STILL ONGOING
IN THE WARNED AREA.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

DRIVING INTO FLOOD WATERS COULD COST YOU YOUR LIFE...OR AT THE VERY
LEAST...THOUSANDS OF DOLLARS OF VEHICLE DAMAGE. NEARLY HALF OF ALL
FLASH FLOOD FATALITIES ARE AUTO RELATED. TURN AROUND...DON'T DROWN.

&&

LAT...LON 3972 7581 3972 7578 3976 7575 3983 7565
      3984 7552 3980 7543 3968 7553 3969 7553
      3966 7554 3963 7560 3960 7560 3953 7565
      3946 7596 3960 7601

$$

TFG

437 
WGUS71 KPHI 301932
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
332 PM EDT SUN JUN 30 2013

MDC015-301940-
/O.CAN.KPHI.FF.W.0023.000000T0000Z-130630T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CECIL MD-
332 PM EDT SUN JUN 30 2013

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EASTERN CECIL
COUNTY...

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.

LAT...LON 3976 7575 3983 7564 3984 7551 3980 7543
      3968 7553 3968 7554 3967 7554 3963 7560
      3960 7560 3953 7565 3952 7577 3965 7577
      3972 7578

$$

DEC003-302145-
/O.CON.KPHI.FF.W.0023.000000T0000Z-130630T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE DE-
332 PM EDT SUN JUN 30 2013

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM EDT FOR
NORTHERN NEW CASTLE COUNTY...

AT 328 PM EDT...PRECIPITATION WAS ENDING ACROSS NEW CASTLE COUNTY.
PLEASE BE WARY OF RESIDUAL ONGOING FLOODING AND DO NOT DRIVE AROUND
BARRICADES.
 
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 3976 7575 3983 7564 3984 7551 3980 7543
      3968 7553 3968 7554 3967 7554 3963 7560
      3960 7560 3953 7565 3952 7577 3965 7577
      3972 7578

$$

TFG

609 
WGUS71 KPHI 302026
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
426 PM EDT SUN JUN 30 2013

DEC003-302035-
/O.CAN.KPHI.FF.W.0023.000000T0000Z-130630T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW CASTLE DE-
426 PM EDT SUN JUN 30 2013

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR NORTHERN NEW CASTLE
COUNTY...

THE WATERS FROM THE EARLIER HEAVY RAINS ARE RECEDING AND FLOOD WATERS
NO LONGER POSE AN IMMINENT THREAT TO LIFE OR PROPERTY. THEREFORE...
THE FLASH FLOOD WARNING HAS BEEN CANCELLED.

PLEASE BE ADVISED THAT THERE ARE STILL SOME WIDELY SCATTERED 
THUNDERSTORMS IN LOWER DELMARVA AND THERE IS A POSSIBILITY A NEW
FLASH FLOOD WARNING MAY BE NEEDED LATER TODAY.
 
LAT...LON 3976 7575 3983 7564 3984 7551 3980 7543
      3968 7553 3968 7554 3967 7554 3963 7560
      3960 7560 3953 7565 3952 7577 3965 7577
      3972 7578

$$

TFG

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 11:18 AM EDT	Areal Flood Advisory	PHI	Chester	117 min
Jun 30, 12:03 PM EDT	Special Weather Statement	PHI	Delaware	42 min
Jun 30, 12:15 PM EDT	Areal Flood Advisory	PHI	Berks	60 min
Jun 30, 12:49 PM EDT	Flash Flood Warning	PHI	Berks	116 min
Jun 30, 2:04 PM EDT	Flash Flood Warning	PHI	Berks	6 hr
Jun 30, 3:29 PM EDT	Areal Flood Advisory	PHI	Carbon, Monroe	4 hr
Jun 30, 11:05 AM EDT	Special Weather Statement	PHI	Cecil	40 min
Jun 30, 12:29 PM EDT	Special Weather Statement	PHI	Kent, Queen Anne's	46 min
Jun 30, 12:34 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Queen Anne's	41 min
Jun 30, 1:28 PM EDT	Special Weather Statement	PHI	Queen Anne's	62 min
Jun 30, 1:34 PM EDT	Areal Flood Advisory	PHI	Kent, Queen Anne's	5 hr
Jun 30, 6:48 PM EDT	Areal Flood Advisory	PHI	Kent, Queen Anne's	4 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2013 Flash Flood Warnings in Maryland, 2013 Flash Flood Warnings in Delaware, 2013 Every flash flood warning in 2013

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.