Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 88, NWS Pittsburgh, PA

July 22, 1990Allegheny County, Butler County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 22, 1990, 4:18 PM EDT for Allegheny County, Butler County, Pennsylvania. It was in force for 102 min.

The area

The counties it named.

The facts

Issued
Jul 22, 1990, 4:18 PM EDT (20:18 UTC)
Expired
Jul 22, 1990, 6:00 PM EDT
In force
102 min
Issued by
NWS Pittsburgh, PA
Area
Whole counties

Counties Allegheny County, PA, Butler 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, 8.3 hours before the alert went out and 34 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 1990-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 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 1990-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
6 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
609 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
82 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 222019
FFWPIT
PAC005-019-222200-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
418 PM EDT SUN JUL 22 1990
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  600 PM EDT
FOR THE FOLLOWING LOCATIONS...
 
IN WEST PENNSYLVANIA
 
   ...ARMSTRONG COUNTY...BUTLER COUNTY
 
AT 418 PM WEATHER RADAR SHOWED THUNDERSTORMS OVER BUTLER AND ARMSTRONG
COUNTIES. THESE STORMS ARE PRODUCING TORRENTIAL DOWNPOURS. NEARLY .75
OF AN INCH OF RAIN FELL IN A HALF HOUR IN BUTLER COUNTY NEAR THE CITY
OF BUTLER.
 
MOST DEATHS IN FLASH FLOODING OCCUR IN AUTOMOBILES.  DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A
SMALL ONE...ON FOOT.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 8:48 PM EDTFlash Flood WarningPBZFayette, Greene2 hr
Jul 22, 5:31 PM EDTTornado WarningPBZBeaver59 min
Jul 22, 5:58 PM EDTTornado WarningPBZButler62 min
Jul 22, 6:38 PM EDTFlash Flood WarningPBZClearfield67 min
Jul 22, 6:57 PM EDTTornado WarningPBZButler63 min
Jul 22, 7:24 PM EDTSevere Thunderstorm WarningPBZClarion66 min

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.