Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 47, NWS Pittsburgh, PA

July 12, 1990Armstrong County, Clarion County, Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 12, 1990, 10:35 AM EDT for Armstrong County, Clarion County, Jefferson County, Pennsylvania. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Jul 12, 1990, 10:35 AM EDT (14:35 UTC)
Expired
Jul 12, 1990, 2:00 PM EDT
In force
3 hr
Issued by
NWS Pittsburgh, PA
Area
Whole counties

Counties Armstrong County, PA, Clarion County, PA, Jefferson 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, 2.6 hours before the alert went out and 98 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 1990-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 89 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 1990-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 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
89 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
567 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KPIT 121437
FFWPIT
PAC031-065-005-121800-

BULLETIN  BROADCAST IMMEDIATELY
FLOOD WARNING FOR STREAMS AND CREEKS
NATIONAL WEATHER SERVICE PITTSBURGH PA
1035 AM EDT THU JUL 12 1990

THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A FLOOD WARNING
FOR STREAMS AND CREEKS UNTIL 200PM EDT FOR THESE COUNTIES IN

WESTERN PENNSYLVANIA...

CLARION COUNTY...JEFFERSON COUNTY...ARMSTRONG COUNTY

AT 1030AM WEATHER SERVICE RADAR INDICATED HEAVY RAINS MOVING
NORTHEASTWARD TOWARD AND ACROSS THESE THREE COUNTIES.

THE SOILS ARE QUITE SATURATED AND RAINFALL OVER THE LAST 24 HOURS IN
THESE COUNTIES RANGED FROM 1.5 TO 2.3 INCHES.

STREAMS AND CREEKS IN THESE COUNTIES ARE REPORTED QUITE HIGH AND
NEAR BANKFUL. THE HEAVY RAINS MOVING ACROSS THESE THREE COUNTIES WILL
RESULT IN FLOODING THIS MORNING.

AT THE PRESENT TIME IT WOULD APPEAR THAT SOUTHERN JEFFERSON AND SOUTHERN
CLARION COUNTIES HAVE THE HIGHEST POTENTIAL FOR FLOODING AS WELL AS THE
NORTHERN HALF OF ARMSTRONG COUNTY.

ROADS ARE CLOSED IN BUTLER COUNTY DUE TO FLOODING IN THE TOWNSHIPS OF
LANCASTER...CENTER AND FORWARD.
A FLOOD WARNING ALSO CONTINUES UNTIL 1PM FOR BEAVER AND BUTLER COUNTIES.
..AND UNTIL 2PM FOR LAWRENCE COUNTY.

A FLOOD WARNING FOR STREAMS AND CREEKS 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.

FURTHER FLOOD WARNINGS FOR STREAMS AND CREEKS MAYb HAVE TO BE ISSUED FOR
OTHER COUNTIES IN WESTERN PENNSYLVANIA THIS MORNING AND AFTERNOON.

A FLOOD WATCH IS IN EFFECT FOR MOST OF WESTERN PENNSYLVANIA AND THE
NORTHERN PANHANDLE OF WEST VIRGINIA UNTIL 10 PM.

SISK/HIGGINS/ALESSI/ROSSI-DRAKE

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 12, 9:20 AM EDTFlash Flood WarningPBZBeaver, Butler4 hr
Jul 12, 12:08 PM EDTFlash Flood WarningPBZIndiana112 min
Jul 12, 12:40 PM EDTFlash Flood WarningPBZArmstrong, Beaver, Butler, Clarion3 hr
Jul 12, 12:40 PM EDTFlash Flood WarningPBZJefferson3 hr
Jul 12, 12:40 PM EDTFlash Flood WarningPBZAllegheny2 hr
Jul 12, 12:40 PM EDTFlash Flood WarningPBZClearfield2 hr
Jul 12, 3:50 PM EDTFlash Flood WarningPBZBedford, Cambria2 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.