Alert archive / Pennsylvania / Flash Flood Warnings in 1990
Flash Flood Warning 87, NWS Pittsburgh, PA
NWS Pittsburgh, PA issued this flash flood warning at Jul 21, 1990, 8:48 PM EDT for Fayette County, Greene County, Pennsylvania. It was in force for 2 hr.
The area
The counties it named.
The facts
- Issued
- Jul 21, 1990, 8:48 PM EDT (00:48 UTC)
- Expired
- Jul 21, 1990, 11:00 PM EDT
- In force
- 2 hr
- Issued by
- NWS Pittsburgh, PA
- Area
- Whole counties
Counties Fayette County, PA, Greene 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 00:00Z, 0.8 hours before the alert went out and 60 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.
- Mixed-layer CAPE
- 97 J/kg
- Mixed-layer CIN
- -11 J/kg
- Mixed-layer LCL
- 730 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- -27 m²/s²
- 0-3 km storm-relative helicity
- 6 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.2
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KPIT 220049 RRA FFWPIT PAC051-059-220300- BULLETIN - EBS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE PITTSBURGH PA 848 PM EDT SAT JUL 21 1990 THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A FLASH FLOOD WARNING EFFECTIVE UNTIL 1100 PM EDT FOR THE FOLLOWING LOCATIONS... IN WEST PENNSYLVANIA ...FAYETTE COUNTY...GREENE COUNTY HEAVY THUNDERSTORMS IN GREENE COUNTY AT 845PM ARE PUSHING INTO FAYETTE COUNTY AND COULD DROP ONE INCH OF RAIN IN ONE HOUR CAUSING FLASH FLOODING. SERIOUS STREET FLOODING HAS ALREADY BEEN REPORTED IN UNIONTOWN IN FAYETTE COUNTY WHERE ALMOST AN INCH OF RAIN FELL BETWEEN 730PM AND 830PM. THERE WAS ALSO FLOODING ON THE REDSTONE AND COALICK R UNIONTOWN. MORE HEAVY THUNDERSTORMS WILL PUSH THROUGH FAYETTE COUNTY W THE NEXT HOUR. 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 FLOWI NG STREAM...EVEN A SMALL ONE...ON FOOT.
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, Jul 21, 7:19 PM EDT, 1 hour 29 minutes before
PAZ003-005-006-013-014-015-WVZ001-230100 SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PITTSBURGH PA 715 PM EDT SAT JUL 21 1990 ...HEAVY RAIN FALLING IN EXTREME SOUTHWEST PENNSYLVANIA AND AND MARHSALL COUNTY WEST VIRGINIA... AT 715 PM PITTSBURGH WEATHER RADAR SHOWED A LINE OF SHOWERS AND STRONG THUNDERSTORMS FROM BELMONT COUNTY OHIO THROUGH MARSHALL COUNTY WEST VIRGINIA ACROSS GREENE AND FAYETTE COUNTIES IN PENNSYLVANIA. THE HEAVIEST RAINS WERE LOCATED OVER MARSHALL COUNTY WEST VIRGINIA ...AND GREENE AND FAYETTE COUNTIES IN PENNSYLVANIA. RAINFALL IN THESE AREAS WAS ESTIMATED TO BE GENERALLY TWO TO FOUR TENTHS /0.2 TO 0.4/ OF AN INCH PER HOUR. SOME ISOLATED AREAS OF FAYETTE COUNTY9 AROUND UNIONTOWN AND EASTERN GREENE COUNTY HAD NEARLY ONE INCH IN ONE HOUR. THESE STORMS COULD DROP RAIN HEAVY ENOUGH TO CAUSE LOWLAND...POOR DRAINAGE AND STREET FLOODING. ALESSI/DRAKE
The office that day
Everything else NWS Pittsburgh, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 22, 4:18 PM EDT | Flash Flood Warning | PBZ | Allegheny, Butler | 102 min |
| Jul 22, 5:31 PM EDT | Tornado Warning | PBZ | Beaver | 59 min |
| Jul 22, 5:58 PM EDT | Tornado Warning | PBZ | Butler | 62 min |
| Jul 22, 6:38 PM EDT | Flash Flood Warning | PBZ | Clearfield | 67 min |
| Jul 22, 6:57 PM EDT | Tornado Warning | PBZ | Butler | 63 min |
| Jul 22, 7:24 PM EDT | Severe Thunderstorm Warning | PBZ | Clarion | 66 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.