Alert archive / Pennsylvania / Flash Flood Warnings in 1989

Flash Flood Warning 18, NWS Philadelphia/Mount Holly

June 22, 1989Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 22, 1989, 5:42 PM EDT for Bucks County, Pennsylvania. It was in force for 75 min.

The area

The counties it named.

The facts

Issued
Jun 22, 1989, 5:42 PM EDT (21:42 UTC)
Expired
Jun 22, 1989, 6:57 PM EDT
In force
75 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, 9.7 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 1989-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1253 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, Atlantic City In, NJ at 12:00Z on 1989-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
1253 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
599 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
0 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 222144
FFWPHL
PAC017-230145-
 
BULLETIN - EBS ACTIVATION REQUESTED
SMALL STREAM WARNING
NATIONAL WEATHER SERVICE PHILADELPHIA PA
542 PM EDT THU JUN 22 1989
 
THE NATIONAL WEATHER SERVICE IN PHILADELPHIA HAS ISSUED A
SMALL STREAM FLOOD WARNING EFFECTIVE UNTIL  945 PM EDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTHEAST PENNSYLVANIA
          ...SOUTHERN BUCKS
 
AT 530 PM THE NESHAMINY CREEK AT LANGHORNE WAS AT 8.77 FT AND
RISING. FLOOD STAGE IS 9 FT. THE CREEK IS EXPECTED TO CREST BETWEEN
10 AND 11 FT AT 8 PM TONIGHT.
 
     HEAVY RAIN IS NO LONGER OCCURRING IN THE WARNED AREA.  HOWEVER
THE CREEK WILL CONTINUE TO RISE DURING THE EVENING DUE TO HEAVY
RAIN EARLIER IN THE DAY.  SCATTERED SHOWERS AND THUNDERSTORMS ARE
STILL POSSIBLE THROUGH THE EVENING HOURS.
 
 
 
 
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.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 22, 2:09 PM EDTFlash Flood WarningPHIBucks, Montgomery, Philadelphia2 hr
Jun 22, 3:15 PM EDTFlash Flood WarningPHIDelaware3 hr
Jun 22, 3:50 PM EDTFlash Flood WarningPHIBucks, Delaware, Montgomery, Philadelphia115 min
Jun 22, 4:30 PM EDTFlash Flood WarningPHIChester, Montgomery2 hr

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.