Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 92, NWS Pittsburgh, PA

August 11, 19904 counties in Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Aug 11, 1990, 2:15 PM EDT for 4 counties in Pennsylvania. It was in force for 60 min.

The area

The counties it named.

The facts

Issued
Aug 11, 1990, 2:15 PM EDT (18:15 UTC)
Expired
Aug 11, 1990, 3:15 PM EDT
In force
60 min
Issued by
NWS Pittsburgh, PA
Area
Whole counties

Counties Allegheny County, PA, Armstrong County, PA, Indiana County, PA, Westmoreland 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

Pittsburgh, PA (KPIT), launched 12:00Z, 6.3 hours before the alert went out and 53 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, Pittsburgh, PA at 12:00Z on 1990-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 65 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, Pittsburgh, PA at 12:00Z on 1990-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 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
65 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
1186 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
27 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 KPIT 111815
FFWPIT
PAC003-005-063-129-111915-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
215 PM EDT SAT AUG 11 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 315 PM EDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

WESTERN PENNSYLVANIA...ALLEGHENY...ARMSTRONG...INDIANA AND 
 WESTMORELAND

AT 210 PM TWO INCHES OF RAIN FELL IN BRADDOCK HILLS AREA OF
ALLEGHENY COUNTY. OTHER OBSERVERS REPORT MORE THAN 1 INCH OF RAIN
AT PENN HILLS. STREETS ARE FLOODED.

THIS AREA OF HEAVY THUNDERSTORMS IS MOVING EAST VERY SLOWLY...INTO
WESTMORELAND...SOUTHERN ARMSTRONG...AND SOUTHERN INDIANA COUNTIES.

IF THREATENING WEATHER APPROACHESk..GO TO A SAFE PLACE IMMEDIATELY.

A FLASH FLOOD WARNING MEANS FLOODING IS IMMINENT OR IN PROGRESS.
IF YOU GET ANY INDICATION THAT FLOOD WATERS ARE APPROACHING..MOVE TO
HIGHER GROUND IMMEDIATELY. DO NOT DRIVE THROUGH FLOODED AREAS.

Nearby

Flash Flood Warnings in Pennsylvania, 1990Every flash flood warning in 1990

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.