Alert archive / Pennsylvania / Flash Flood Warnings in 2001

Flash Flood Warning 42, NWS Philadelphia/Mount Holly

August 11, 2001Bucks County, Pennsylvania; Mercer County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 11, 2001, 11:20 AM EDT for Bucks County, Pennsylvania; Mercer County, New Jersey. 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 counties it named.

The facts

Issued
Aug 11, 2001, 11:20 AM EDT (15:20 UTC)
Expired
Aug 11, 2001, 2:15 PM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

Counties Mercer County, NJ, Bucks County, PA

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 3.3 hours before the alert went out and 183 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, Brookhaven, NY at 12:00Z on 2001-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2001-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -25 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1451 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
-25 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.8

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 111525
FFWPHI
NJC021-PAC017-111815-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1120 AM EDT SAT AUG 11 2001

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN BUCKS COUNTY IN PENNSYLVANIA
  MERCER COUNTY IN CENTRAL NEW JERSEY

* UNTIL 215 PM EDT.

* AT 1117 AM EDT...WEATHER SERVICE RADAR INDICATED THAT AROUND
  2.5 INCHES OF RAIN HAS FALLEN WITHIN THE PAST HOUR OVER
  WESTERN MERCER COUNTY AND ADJACENT PARTS OF BUCKS COUNTY NEAR
  YARDLEY. THE THUNDERSTORMS ARE SHOWING LITTLE MOVEMENT...
  ALTHOUGH THEY ARE WEAKENING. 

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. 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.

FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER
RADIO...YOUR LOCAL RADIO OR TELEVISION STATION...OR YOUR CABLE
TELEVISION OUTLET.

$$

LAT...LON 4036 7462 4022 7457 4017 7471 4034 7483

TFG/JAQ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 10:17 AM EDTFlash Flood WarningPHIBerks3 hr
Aug 11, 11:35 AM EDTFlash Flood WarningPHILehigh3 hr
Aug 11, 12:55 PM EDTFlash Flood WarningPHIBerks3 hr
Aug 11, 2:45 PM EDTFlash Flood WarningPHILehigh90 min
Aug 11, 7:35 AM EDTFlash Flood WarningPHIAtlantic3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2001Flash Flood Warnings in New Jersey, 2001Every flash flood warning in 2001

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.