Alert archive / Pennsylvania / Flash Flood Warnings in 2006

Flash Flood Warning 74, NWS Philadelphia/Mount Holly

November 16, 2006Chester County, Pennsylvania; Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this flash flood warning at Nov 16, 2006, 5:00 PM EST for Chester County, Pennsylvania; Cecil County, Maryland. It was in force for 3 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
Nov 16, 2006, 5:00 PM EST (22:00 UTC)
Expired
Nov 16, 2006, 8:00 PM EST
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

Counties Cecil County, MD, Chester County, PA

The radar

The Dover AFB radar (KDOX), 118 km from the middle of the area, began a volume at 22:00 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.0 hours before the alert went out and 161 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 2006-11-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 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 2006-11-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 471 square meters per square second.19395878Sfc1 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
6 J/kg
Mixed-layer CIN
-72 J/kg
Mixed-layer LCL
610 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
471 m²/s²
0-3 km storm-relative helicity
481 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 162201
FFWPHI
MDC015-PAC029-170100-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
500 PM EST THU NOV 16 2006

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN CECIL COUNTY IN NORTHEAST MARYLAND...
  CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 800 PM EST

* AT 459 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  HEAVY RAINS FROM THUNDERSTORMS OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  PARKESBURG...LIONVILLE...KENNETT SQUARE...HONEY BROOK...
  DOWNINGTOWN...COATESVILLE AND WEST GROVE

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. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

LAT...LON 3962 7613 3962 7582 4016 7556 4010 7592

$$

WN

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 16, 3:32 PM ESTWind AdvisoryPHIDelaware, Philadelphia3 hr
Nov 16, 4:44 PM ESTFlash Flood WarningPHIBerks3 hr
Nov 16, 5:03 PM ESTFlash Flood WarningPHICarbon, Monroe3 hr
Nov 16, 5:24 PM ESTFlash Flood WarningPHIBucks, Lehigh, Montgomery, Northampton3 hr
Nov 16, 5:12 PM ESTCoastal Flood WarningPHICaroline, Cecil, Kent, Queen Anne's, Talbot11 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2006Flash Flood Warnings in Maryland, 2006Every flash flood warning in 2006

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.