Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 82, NWS Pittsburgh, PA

July 20, 1990Fayette County, Somerset County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 20, 1990, 5:01 PM EDT for Fayette County, Somerset County, Pennsylvania. It was in force for 119 min.

The area

The counties it named.

The facts

Issued
Jul 20, 1990, 5:01 PM EDT (21:01 UTC)
Expired
Jul 20, 1990, 7:00 PM EDT
In force
119 min
Issued by
NWS Pittsburgh, PA
Area
Whole counties

Counties Fayette County, PA, Somerset 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, 9.0 hours before the alert went out and 83 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 1990-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 66 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 1990-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 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
66 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
1131 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
117 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 202102 RRA
FFWPIT
PAC051-111-202300-
 
BULLETIN - EBS ACTIVATION REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
501 PM EDT FRI JUL 20 1990
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
EFFECTIVE UNTIL  700 PM EDT
FOR THE FOLLOWING LOCATIONS...
 
IN WEST PENNSYLVANIA
 
   ...FAYETTE COUNTY...SOMERSET COUNTY
 
AT 450PM WEATHER SERVICE RADAR INDICATED SEVERE THUNDERSTORMS WITH
RAIN HEAVY ENOUGH TO CAUSE FLASH FLOODING PUSHING THROUGH FAYETTE
AND SOMERSET COUNTIES.  THESE STORMS HAVE DOWNED TREES AND CONTAINED
TORRENTIAL DOWNPOURS THAT CAUSED SERIOUS STREET AND POOR DRAINAGE
FLOODING.
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
 
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIV	E INTO AREAS WHERE WATER COVERS THE ROAD.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 2:12 PM EDTSevere Thunderstorm WarningPBZArmstrong, Butler, Clarion63 min
Jul 20, 2:55 PM EDTFlash Flood WarningPBZWestmoreland65 min
Jul 20, 2:55 PM EDTSevere Thunderstorm WarningPBZWestmoreland65 min
Jul 20, 4:12 PM EDTSevere Thunderstorm WarningPBZCambria63 min
Jul 20, 4:12 PM EDTSevere Thunderstorm WarningPBZGreene63 min
Jul 20, 4:24 PM EDTSevere Thunderstorm WarningPBZSomerset66 min
Jul 20, 5:01 PM EDTSevere Thunderstorm WarningPBZFayette, Somerset119 min
Jul 20, 6:29 PM EDTFlash Flood WarningPBZButler2 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.