Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 91, NWS Pittsburgh, PA

July 22, 1990Clarion County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 22, 1990, 11:35 PM EDT for Clarion County, Pennsylvania. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Jul 22, 1990, 11:35 PM EDT (03:35 UTC)
Expired
Jul 23, 1990, 4:00 AM EDT
In force
4 hr
Issued by
NWS Pittsburgh, PA
Area
Whole counties

County Clarion 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, 3.6 hours before the alert went out and 104 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 1990-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 265 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 1990-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 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
265 J/kg
Mixed-layer CIN
-11 J/kg
Mixed-layer LCL
828 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
111 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPIT 230337
FFWPIT
PAC031-230800-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
1135 PM EDT SUN JUL 22 1990
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  400 AM EDT
FOR THE FOLLOWING LOCATION...
 
IN WEST PENNSYLVANIA
 
   ...CLARION COUNTY
 
THE FLASH FLOOD WARNING FOR CLARION COUNTY HAS BEEN EXTENDED TO 4 AM.
 
NATIONAL WEATHER SERVICE RADAR ESTIMATES AND GROUND REPORTS INDICATE
FLOODING WILL CONTINUE THROUGH THE EARLY MORNING HOURS.
 
SOME ROADS WERE FLOODED AND CLOSED.  IN PARTICULAR WAS ROUTE 208
BETWEEN EMLENTON AND KNOX WHERE TWO FEET OF WATER COVERED THE ROAD.
 
 
 
 
 
 
BE ESPECIALLY CAUTI3OUS 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.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 22, 8:02 PM EDTSevere Thunderstorm WarningPBZBeaver58 min
Jul 22, 8:07 PM EDTTornado WarningPBZButler53 min
Jul 22, 8:31 PM EDTSevere Thunderstorm WarningPBZWashington59 min
Jul 22, 8:52 PM EDTFlash Flood WarningPBZClarion3 hr
Jul 22, 9:01 PM EDTSevere Thunderstorm WarningPBZBeaver59 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.