Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 16, NWS Pittsburgh, PA

June 28, 1990Allegheny County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jun 28, 1990, 2:44 PM EDT for Allegheny County, Pennsylvania. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Jun 28, 1990, 2:44 PM EDT (18:44 UTC)
Expired
Jun 28, 1990, 5:00 PM EDT
In force
2 hr
Issued by
NWS Pittsburgh, PA
Area
Whole counties

County Allegheny 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, 6.7 hours before the alert went out and 12 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 1990-06-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 165 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 1990-06-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 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
165 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
1222 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
106 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 281844
FFWPIT
PAC003-282100-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
244 PM EDT THU JUN 28 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 500 PM EDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

WESTERN PENNSYLVANIA...ALLEGHENY

AT 240 PM NEARLY 2 INCHES OF RAIN WAS REPORTED IN ALLEGHENY COUNTY
ALONG PINE CREEK IN NORTHERN ALLEGHENY COUNTY...AND ALONG LITTLE
DEER CREEK IN INDIANA TOWNSHIP...ALLEGHENY COUNTY. FLASH FLOODING
IS IMMINENT IN THOSE AREAS.

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.x DO NOT DRIVE THROUGH FLOODED AREAS.

 A FLASH FLOOD WATCH WILL BE EXTENDED EASTWARD INTO ARMSTRONG AND
WESTMORELAND COUNTY.

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jun 28, 1:09 PM EDT, 1 hour 35 minutes before
PAZ003-015-282300-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
110 PM EDT THU JUN 28 1990

SLOW MOVING HEAVY THUNDERSTORMS ARE IN LAWRENCE COUNTY PENNSYLVANIA.
THEY HAVE HEAVY DOWNPOURS AND FREQUENT LIGHTNING. THE THUNDERSTORMS
IN LAWRENCE COUNTY ARE MOVING EAST AT 25 MPH.

A NEW AREA OF THUNDERSTORMS IS ABOUT TO MOVE INTO BEAVER COUNTY
PENNSYLVANIA...NORTHWEST OF PITTSBURGH.

DRIVE CAREFULLY IN THE HEAVY DOWNPOURS AND LOOK FOR PONDING OF WATER
IN THE USUAL LOW SPOTS.
Special weather statement, Jun 28, 1:59 PM EDT, 45 minutes before
PAZ003-015-282300-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
200 PM EDT THU JUN 28 1990

HEAVY THUNDERSTORMS HAVE MOVED INTO ALLEGHENY...BUTLER...AND
ARMSTRONG COUNTIES. THEY ARE MOVING EAST AT 25 MPH AND WILL REACH
INDIANA AND WESTMORELAND BY 3 PM.

YOU CAN EXPECT HEAVY DOWNPOURS...FREQUENT DANGEROUS LIGHTNING...AND
GUSTY WINDS. IT WOULD TAKE SLIGHTLY OVER 2 INCHES OF RAIN IN A SHORT
TIME TO CAUSE FLOODING.

AS YOY DRIVE..F.BE ON THE CONSTANT LOOKOUT FOR PONDING ON WATER
IN LOW SPOTS ON ROADWAYS.

The office that day

Everything else NWS Pittsburgh, PA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 28, 5:45 PM EDTFlash Flood WarningPBZAllegheny, Washington, Westmoreland2 hr

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.