Alert archive / Pennsylvania / Flash Flood Warnings in 1996

Flash Flood Warning 59, NWS Philadelphia/Mount Holly

July 31, 1996Bucks County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 31, 1996, 11:17 AM EDT for Bucks County, Philadelphia County, Pennsylvania. It was in force for 118 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 31, 1996, 11:17 AM EDT (15:17 UTC)
Expired
Jul 31, 1996, 1:15 PM EDT
In force
118 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

Counties Bucks County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 65 km from the middle of the area, began a volume at 15:18 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, 3.3 hours before the alert went out and 114 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, Phillips Aaf/Abe, MD at 12:00Z on 1996-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1268 joules per kilogram.LCLLFCEL10008507005003002001001 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, Phillips Aaf/Abe, MD at 12:00Z on 1996-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 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
1268 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
474 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPHL 311518
FFWPHL
PAC017-101-311715-
 
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHILADELPHIA/MOUNT HOLLY NJ
1117 AM EDT WED JUL 31 1996
 
THE NATIONAL WEATHER SERVICE IN PHILADELPHIA/MOUNT HOLLY HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  115 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN  PENNSYLVANIA
 
   ...SOUTHERN BUCKS COUNTY...PHILADELPHIA COUNTY
 
NATIONAL WEATHER SERVICE RADAR AND OBSERVERS INDICATED TORRENTIAL
DOWNPOURS IN PHILADELPHIA AND BUCKS COUNTIES. THE HEAVIEST RAINFALL WAS
NEAR THE DELAWARE RIVER WHERE RAINFALL RATES EXCEEDED 2 INCHES IN AN
HOUR.
 
DO NOT ATTEMPT TO DRIVE THROUGH FLOODED AREAS.  THE DEPTH OF THE
WATER MAY BE HIGHER THZAN YOU THINK.  RAPIDLY RISING WATERS CAN
QUICKLY ENGULF YOUR VEHICLE AND ITS OCCUPANTS...WASHING THEM AWAY.
REMEMBER...MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES.

Nearby

Flash Flood Warnings in Pennsylvania, 1996Every flash flood warning in 1996

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.