Alert archive / Pennsylvania / Flash Flood Warnings in 1989

Flash Flood Warning 34, NWS Philadelphia/Mount Holly

August 13, 1989Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 13, 1989, 11:05 AM EDT for Bucks County, Pennsylvania. It was in force for 85 min.

The area

The counties it named.

The facts

Issued
Aug 13, 1989, 11:05 AM EDT (15:05 UTC)
Expired
Aug 13, 1989, 12:30 PM EDT
In force
85 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

County Bucks County, PA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Atlantic City In, NJ (KACY), launched 12:00Z, 3.1 hours before the alert went out and 111 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, Atlantic City In, NJ at 12:00Z on 1989-08-13Temperature 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, Atlantic City In, NJ at 12:00Z on 1989-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 square meters per square second.1939Sfc1 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
NaN m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
89 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 
TTAA00 KPHL 131510 COR
FFWPHL
PAC017-131630-

BULLETIN - EBS ACTIVATION REQUESTED
URBAN FLOOD WARNING...CORRECTION
NATIONAL WEATHER SERVICE PHILADELPHIA PA
1105 AM EDT SUN AUG 13 1989

THE NATIONAL WEATHER SERVICE IN PHILADELPHIA HAS ISSUED AN

URBAN FLOOD WARNING EFFECTIVE UNTIL 1230 PM EDT
FOR PEOPLE IN THE FOLLOWING COUNTY...

IN SOUTHEAST PENNSYLVANIA
          ...CENTRAL AND SOUTHERN BUCKS

AT 1100 AM WEATHER SERVICE RADAR SHOWED HEAVY RAIN OVER CENTRAL
AND SOUTHERN BUCKS COUNTY IN PENNSYLVANIA. A WEATHER SPOTTER NEAR
PERKASIE PENNSYLVANIA REPORTED 2 1/2 INCHES OF RAIN IN 45 MINUTES.
THIS HEAVY RAIN WAS MOVING VERY SLOWLY EAST BUT KEPT REDEVELOPING
OVER SOUTHERN BUCKS COUNTY. THE HEAVY RAIN SHOULD MOVE OUT BUCKS
COUNTY BY 1230 PM EDT.

THESE HEAVY RAINS WILL CAUSE FLOODING OF ROADWAYS AND POOR DRAINAGE
AREAS.


IF YOU ARE IN THE WARNED COUNTY IN AN AREA SUBJECT TO FLOODING
MOVE TO HIGHER GROUND.  DO NOT DRIVE THROUGH FLOOD WATERS.
CLIMBING ATOP YOUR STALLED VEHICLE WILL NOT PREVENT YOU FROM
BEING SWEPT INTO DANGEROUS STREAM CONDITIONS AS WATER LEVELS RISE.

RNS

Nearby

Flash Flood Warnings in Pennsylvania, 1989Every flash flood warning in 1989

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.