Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 99, NWS Pittsburgh, PA

September 7, 1990Washington County, Pennsylvania; Brooke County, West Virginia

NWS Pittsburgh, PA issued this flash flood warning at Sep 7, 1990, 4:00 AM EDT for Washington County, Pennsylvania; Brooke County, West Virginia. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Sep 7, 1990, 4:00 AM EDT (08:00 UTC)
Expired
Sep 7, 1990, 8:00 AM EDT
In force
4 hr
Issued by
NWS Pittsburgh, PA
Area
Whole counties

Counties Washington County, PA, Brooke County, WV

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 00:00Z, 8.0 hours before the alert went out and 33 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 00:00Z on 1990-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 62 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 00:00Z on 1990-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 107 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
62 J/kg
Mixed-layer CIN
-179 J/kg
Mixed-layer LCL
1475 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
107 m²/s²
0-3 km storm-relative helicity
165 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 070800
FFWPIT
PAC125-WVC009-071200-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
400 AM EDT FRI SEP 7 1990
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  800 AM EDT
FOR THE FOLLOWING LOCATIONS...
 
IN WEST PENNSYLVANIA
 
   ...WASHINGTON COUNTY
 
 
IN THE WEST VIRGINIA PANHANDLE
 
   ...BROOKE COUNTY
 
FLOODING CONTINUES IN FOLLANSBEE IN BROOKE COUNTY AND ALONG CROSS
CREEK IN BROOKE AND WASHINGTON COUNTY. WIDESPREAD FLOODING PROBLEMS
ARE REPORTED IN WASHINGTON COUNTYH. THE HEAVY RAINS ARE BEGINNING TO
SUBSIDE IN THESE AREAS...BUT STREAMS WILL CONTINUE TO RISE FOR SEVERAL
HOURS. ANOTHER AREA OF HEAVY RAIN IN NORTHEAST OHIO WILL MOVE INTO THE
WARNING AREA 600 AM.
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE
THE DANGERS OF FLOODS AND FLASH FLOODS.  IF FLASH FLOODING IS
OBSERVED...ACT QUICKLY.  MOVE UP TO ESCAPE FLOOD WATERS.  DO
NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE 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
ABANDONED QUICKLY.  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, Sep 6, 10:18 PM EDT, 5 hours 42 minutes before
PAZ001>006-013>015-WVZ001-070400-

SPECIAL WEATHER STATEMENT AND WEATHER RADAR SUMMARY
NATIONAL WEATHER SERVICE PITTSBURGH PA
1020 PM EDT THU SEP 6 1990

...FLASH FLOOD WATCH TIL 4 AM FRIDAY FOR ALL OF WESTERN PENNSYLVANIA
   AND THE NORTHERN WEST VIRGINIA PANHANDLE...

...TORNADO WATCH FOR NORTHWESTERN PENNSYLVANIA TIL 1 AM...

...SEVERE THUNDERSTORM WATCH FOR SOUTHWESTERN PENNSYLVANIA...
   SOUTHERN MOUNTAINS...AND WEST VIRGINIA NORTHERN PANHANDLE
   TIL 4 AM...

...SEVERE THUNDERSTORM WARNINGS FOR AT LEAST 8 WESTERN PENNSYLVANIA
   COUNTIES AND 4 NORTHERN WEST VIRGINIA PANHANDLE COUNTIES TIL AROUND
   11 PM...

RADAR SHOWED THE LINE OF SEVERE STORMS ALONG INTERSTATE 80 MOVING
SOUTHWARD AT 30 MPH INTO SOUTHERN PENNSYLVANIA AND THE WEST VIRGINIA
PANHANDLE.  THE STORMS WILL BE MOVING THROUGH THE PITTSBURGH AREA
BETWEEN 1030 AND 11 PM.  THESE STORMS ARE DANGEROUS...SO TAKE COVER.
ALSO PULL OVER AND SEEK HIGHER GROUND IF ROADS BECOME FLOODED.
IF HEAVY DOWNPOURS PERSIST...WATCH FOR SMALL STREAMS GOING OUT OF THEIR
BANKS.
Special weather statement, Sep 6, 11:41 PM EDT, 4 hours 19 minutes before
PAZ001>006-013>015-WVZ001-070500-

SPECIAL WEATHER STATEMENT AND WEATHER RADAR SUMMARY
NATIONAL WEATHER SERVICE PITTSBURGH PA
1140 PM EDT THU SEP 6 1990

...FLASH FLOOD WATCH TIL 4 AM FRIDAY FOR ALL OF WESTERN PENNSYLVANIA
   AND THE NORTHERN WEST VIRGINIA PANHANDLE...

...TORNADO WATCH FOR NORTHWESTERN PENNSYLVANIA TIL 1 AM...

...SEVERE THUNDERSTORM WATCH FOR SOUTHWESTERN PENNSYLVANIA...
   SOUTHERN MOUNTAINS...AND WEST VIRGINIA NORTHERN PANHANDLE
   TIL 4 AM...

...SEVERE THUNDERSTORM WARNING FOR 4 SOUTHWESTERN PENNSYLVANIA
   COUNTIES TIL MIDNIGHT...

RADAR SHOWED ONE LINE OF STORMS OVER THE WEST VIRGINIA NORTHERN
PANHANDLE AND SOUTHWESTERN PENNSYLVANIA...FROM WHEELING WV AND
GREENSBURG PA TO TYRONE IN THE SOUTH CENTRAL PENNSYLVANIA MOUNTAINS.
THESE STORMS WERE CONTINUING TO MOVE SOUTHEASTWARD AT 30 MPH INTO
EXTREME SOUTHERN PENNSYLVANIA.  OHIO COUNTY WEST VIRGINIA AND
WASHINGTON COUNTY PENNSYLVANIA ARE PRONE TO GET HEAVY THUNDERSTORM
RAINS TIL 1 AM.  IF YOU ARE IN AN AREA PRONE TO FLOODING FROM SMALL
STREAMS OR POOR DRAINAGE...WATCH FOR THESE REPEATED HEAVY DOWNPOURS AND
RISING WATER.  BE READY TO MOVE TO HIGHER GROUND.

STEADY RAIN WAS FALLING OVER MUCH OF NORTHWESTERN PENNSYLVANIA.  A NEW
LINE OF THUNDERSTORMS WAS OVER LAKE ERIE ABOUT TO MOVE ONSHORE INTO
NORTHERN OHIO AND ERIE COUNTY PENNSYLVANIA.  THESE STORMS TOO WERE
MOVING SOUTHEASTWARD AT 30 MPH.

ALL OF THE STORMS STILL HAVE ENOUGH PUNCH TO CAUSE WIND AND LIGHTNING
DAMAGE WITH POSSIBLY HAIL AS WELL.  THE MORE THE HEAVY RAIN
CONTINUES...THE MORE CHANCE THERE WILL BE FLOODING.  FIRST WITH ROADS
AND BASEMENTS AND LATER POSSIBLY CREEKS AND SMALL STREAMS.
Special weather statement, Sep 6, 11:44 PM EDT, 4 hours 16 minutes before
PAZ001>006-013>015-WVZ001-070500-

SPECIAL WEATHER STATEMENT AND WEATHER RADAR SUMMARY
NATIONAL WEATHER SERVICE PITTSBURGH PA
1140 PM EDT THU SEP 6 1990

...FLASH FLOOD WATCH TIL 4 AM FRIDAY FOR ALL OF WESTERN PENNSYLVANIA
   AND THE NORTHERN WEST VIRGINIA PANHANDLE...

...TORNADO WATCH FOR NORTHWESTERN PENNSYLVANIA TIL 1 AM...

...SEVERE THUNDERSTORM WATCH FOR SOUTHWESTERN PENNSYLVANIA...
   SOUTHERN MOUNTAINS...AND WEST VIRGINIA NORTHERN PANHANDLE
   TIL 4 AM...

...SEVERE THUNDERSTORM WARNING FOR 4 SOUTHWESTERN PENNSYLVANIA
   COUNTIES TIL MIDNIGHT...

RADAR SHOWED ONE LINE OF STORMS OVER THE WEST VIRGINIA NORTHERN
PANHANDLE AND SOUTHWESTERN PENNSYLVANIA...FROM WHEELING WV AND
GREENSBURG PA TO TYRONE IN THE SOUTH CENTRAL PENNSYLVANIA MOUNTAINS.
THESE STORMS WERE CONTINUING TO MOVE SOUTHEASTWARD AT 30 MPH INTO
EXTREME SOUTHERN PENNSYLVANIA.  OHIO COUNTY WEST VIRGINIA AND
WASHINGTON COUNTY PENNSYLVANIA ARE PRONE TO GET HEAVY THUNDERSTORM
RAINS TIL 1 AM.  IF YOU ARE IN AN AREA PRONE TO FLOODING FROM SMALL
STREAMS OR POOR DRAINAGE...WATCH FOR THESE REPEATED HEAVY DOWNPOURS AND
RISING WATER.  BE READY TO MOVE TO HIGHER GROUND.

STEADY RAIN WAS FALLING OVER MUCH OF NORTHWESTERN PENNSYLVANIA.  A NEW
LINE OF THUNDERSTORMS WAS OVER LAKE ERIE ABOUT TO MOVE ONSHORE INTO
NORTHERN OHIO AND ERIE COUNTY PENNSYLVANIA.  THESE STORMS TOO WERE
MOVING SOUTHEASTWARD AT 30 MPH.

ALL OF THE STORMS STILL HAVE ENOUGH PUNCH TO CAUSE WIND AND LIGHTNING
DAMAGE WITH POSSIBLY HAIL AS WELL.  THE MORE THE HEAVY RAIN
CONTINUES...THE MORE CHANCE THERE WILL BE FLOODING.  FIRST WITH ROADS
AND BASEMENTS AND LATER POSSIBLY CREEKS AND SMALL STREAMS.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 9:42 PM EDTSevere Thunderstorm WarningPBZBeaver, Washington78 min
Sep 6, 9:42 PM EDTSevere Thunderstorm WarningPBZGreene78 min
Sep 6, 9:42 PM EDTSevere Thunderstorm WarningPBZArmstrong, Clarion, Jefferson78 min
Sep 6, 9:42 PM EDTSevere Thunderstorm WarningPBZAllegheny, Butler78 min
Sep 6, 11:00 PM EDTSevere Thunderstorm WarningPBZAllegheny, Fayette, Washington, Westmoreland60 min
Sep 7, 12:06 AM EDTFlash Flood WarningPBZWashington4 hr
Sep 7, 12:06 AM EDTFlash Flood WarningPBZAllegheny, Westmoreland4 hr
Sep 7, 7:30 AM EDTFlash Flood WarningPBZWashington3 hr
Sep 7, 9:45 AM EDTFlash Flood WarningPBZWashington4 hr
Sep 7, 1:50 PM EDTFlash Flood WarningPBZWashington3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 1990Flash Flood Warnings in West Virginia, 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.