Alert archive / Pennsylvania / Flash Flood Warnings in 1991

Flash Flood Warning 4, NWS Cleveland, OH

April 28, 1991McKean County, Pennsylvania

NWS Cleveland, OH issued this flash flood warning at Apr 28, 1991, 8:20 PM EDT for McKean County, Pennsylvania. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Apr 28, 1991, 8:20 PM EDT (00:20 UTC)
Expired
Apr 28, 1991, 11:15 PM EDT
In force
3 hr
Issued by
NWS Cleveland, OH
Area
Whole counties

County McKean County, PA

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 0.3 hours before the alert went out and 125 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, Buffalo Intl Airport, NY at 00:00Z on 1991-04-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Buffalo Intl Airport, NY at 00:00Z on 1991-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 square meters per square second.19395878Sfc1 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
3 J/kg
Mixed-layer CIN
-376 J/kg
Mixed-layer LCL
1161 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
142 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 KERI 290020
FFWERI
PAC083-290315-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
FLASH FLOOD WARNING 
NATIONAL WEATHER SERVICE ERIE PA
820 PM EDT SUN APR 28 1991

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 1115 PM EDT FOR PEOPLE IN THE FOLLOWING COUNTY

   IN THE NORTHWEST PART OF PENNSYLVANIA
      MCKEAN

AT 815 PM EDT THIS SUNDAY EVENING WEATHER SERVICE RADAR CONTINUED
O INDICATE STRONG THUNDERSTORMS CONTAINING HEAVY DOWNPOURS THAT
WERE SLOWLY MOVING ACROSS MOST OF MCKEAN COUNTY.
FLOODING OF BASEMENTS AND ROADS HAS BEEN REPORTED IN SMETHPORT.
BECAUSE OF THE SLOW MOVEMENT OF THESE STORMS THE THREAT OF FLOODING
WILL CONTINUE THROUGH THE EVENING HOURS.

A FLASH FLOOD WARNING MEANS FLOODING IS OCCURRING OR IS IMMINENT.
MOST FLASH FLOOD DEATHS 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.
TO ESCAPE RISING WATER MOVE TO HIGHER GROUND.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE WATER COVERS THE ROADWAY.
THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY.
VEHICLES CAUGHT IN RISING WATER SHOULD BE ABBANDONED IMMEDIATELY.
MOVE TO HIGHER GROUND.

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, Apr 28, 6:18 PM EDT, 2 hours 2 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ERIE, PA
614 PM EDT SUN APR 28 1991

...AN AREA OF SLOW MOVING THUNDERSTORMS AND RAINSHOWERS CONTINUE TO MOVE
ACROSS NORTHERN AND CENTRAL MCKEAN COUNTY.

THESE THUNDERSTORMS ARE LOCATED NORTH AND SOUTH OF THE CITY OF BRADFORD
AND STRETCH AS FAR SOUTH TO THE COMMUNITIES OF KANE..MT.JEWETT AND LUDLOW.
THESE STROMS WERE MOVING VERY SLOWLY DURING THE PAST HOUR AND HALF. PERSONS
LIVING NEAR POOR DRAINAGE AREAS..SMALL STREAMS AND CREEKS SHOULD BE ON THE
ALERT FOR RISING WATERS.
THESE THUNDERSTORMS IN ADDITION TO HAVING POSSIBLY HEAVY DOWNPOURS COULD
ALSO CONTAIN SOME SMALL HAIL AND DANGEROUS LIGHTNING.

DO NOT DRIVE YOUR CAR THROUGH FLOODED ROADWAYS AND BEWARE OF DEBRIS AND
MUDSLIDES.

WSO ERIE/FPW
Special weather statement, Apr 28, 6:20 PM EDT, 2 hours before
PAZ083-105-290000

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ERIE, PA
620 PM EDT SUN APR 28 1991

...AN AREA OF SLOW MOVING THUNDERSTORMS AND RAINSHOWERS CONTINUE TO MOVE
ACROSS NORTHERN AND CENTRAL MCKEAN COUNTY.

THESE THUNDERSTORMS ARE LOCATED NORTH AND SOUTH OF THE CITY OF BRADFORD
AND STRETCH AS FAR SOUTH TO THE COMMUNITIES OF KANE..MT.JEWETT AND LUDLOW.
THESE STROMS WERE MOVING VERY SLOWLY DURING THE PAST HOUR AND HALF. PERSONS
LIVING NEAR POOR DRAINAGE AREAS..SMALL STREAMS AND CREEKS SHOULD BE ON THE
ALERT FOR RISING WATERS.
THESE THUNDERSTORMS IN ADDITION TO HAVING POSSIBLY HEAVY DOWNPOURS COULD
ALSO CONTAIN SOME SMALL HAIL AND DANGEROUS LIGHTNING.

DO NOT DRIVE YOUR CAR THROUGH FLOODED ROADWAYS AND BEWARE OF DEBRIS AND
MUDSLIDES.
WSO ERIE/FPW/TJP
Special weather statement, Apr 28, 6:46 PM EDT, 1 hour 34 minutes before
OHZ002-003-004-282345-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CLEVELAND OHIO
646 PM EDT SUN APR 28 1991

AN AREA OF SLOW MOVING THUNDERSTORM CONTINUE TO DEVELOP OVER
NORTHEASTERN OHIO.

AT 640 PM EDT AN AREA OF INTENSE SLOW MOVING THUNDERSTORMS WERE OVER
EASTERN CUYAHOGA... NORTHERN SUMMIT AND EASTERN GEAUGA COUNTIES.

CONTINUED HEAVY DOWNPOURS CAN BE EXPECTED WITH THESE STORMS AS THEY
MOVE OVER GEAUGA COUNTY.

MOTORISTS SHOULD USE EXTRA CAUTION WHERE DRAINAGE IS POOR AND PONDING
OF WATER MAY OCCUR. THESE STORMS MAY PRODUCE DANGEROUS LIGHTNING AND
GUSTY WINDS.

JOHNSON
Special weather statement, Apr 28, 7:24 PM EDT, 56 minutes before
OHZ002-003-290025-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CLEVELAND OHIO
725 PM EDT SUN APR 28 1991

A CLUSTER OF THUNDERSTORMS CONTINUE TO MOVE VERY SLOWLY NORTHEAST
ACROSS GEAUGA COUNTY THIS EVENING.

AT 715 PM EDT AN INTENSE SLOW MOVING THUNDERSTORM WAS BETWEEN SOLON AND
BAINBRIDGE MOVING NORTHEAST AT AROUND 5 MPH. AT 705 PM EDT A SKYWARN
OBSERVER ESTIMATED ONE-QUARTER TO ONE-HALF INCH OF RAINFALL IN FIFTEEN
MINUTES IN SOLON.

CONTINUED HEAVY DOWNPOURS CAN BE EXPECTED WITH THESE STORMS AS THEY MOVE
OVER GEAUGA AND LAKE COUNTIES.

MOTORISTS SHOULD USE EXTRA CAUTION WHERE DRAINAGE IS POOR AND PONDING
OF WATER MAY OCCUR. THIS STORM MAY PRODUCE DANGEROUS LIGHTNING...
GUSTY WINDS AND SMALL HAIL.

JOHNSON

The office that day

Everything else NWS Cleveland, OH issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 29, 12:20 AM EDTSevere Thunderstorm WarningCLECrawford55 min

Nearby

Flash Flood Warnings in Pennsylvania, 1991Every flash flood warning in 1991

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.