Alert archive / Pennsylvania / Flash Flood Warnings in 1991

Flash Flood Warning 2, NWS State College, PA

August 9, 1991Dauphin County, Pennsylvania

NWS State College, PA issued this flash flood warning at Aug 9, 1991, 8:15 AM EDT for Dauphin County, Pennsylvania. It was in force for 45 min.

The area

The counties it named.

The facts

Issued
Aug 9, 1991, 8:15 AM EDT (12:15 UTC)
Expired
Aug 9, 1991, 9:00 AM EDT
In force
45 min
Issued by
NWS State College, PA
Area
Whole counties

County Dauphin County, PA

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 0.3 hours before the alert went out and 171 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, Washington/Dulle, VA at 12:00Z on 1991-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 40 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, Washington/Dulle, VA at 12:00Z on 1991-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 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
40 J/kg
Mixed-layer CIN
-91 J/kg
Mixed-layer LCL
645 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
141 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 KHAR 091214
FFWHAR
PAC043-091300-

BULLETIN - EBS ACTIVATION REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE HARRISBURG PA
815 AM EDT FRI AUG 9 1991

THE NATIONAL WEATHER SERVICE IN HARRISBURG HAS EXTENDED THE
FLOOD WARNING EFFECTIVE UNTIL  915 AM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS......

IN SOUTH CENTRAL  PENNSYLVANIA

   ...SOUTHERN DAUPHIN COUNTY

AT 800 AM EDT THE PAXTON CREEK WAS AT 10.1 FEET AND RISING SLOWLY.
AND SHOULD CONTINUE TO RISE SLOWLY DURNG THE NEXT HOUR.

AS RAIN CONTINUES TO FALL IN THE HARRISBURG AREA THE CREEK NO DOUBT
WILL CONTINUE TO RISE AND COMPANIES ALONG THE CREEK SHOULD KEEP AN
EYE ON IT AND TAKE NESSARY ACTION IF THREATEN.

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.

A FLASH FLOOD WARNING MEANS THAT 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 UP TO HIGHER GROUND.

WSO HAR HURLEY

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 6:57 AM EDTFlash Flood WarningCTPDauphin63 min
Aug 9, 9:15 AM EDTFlash Flood WarningCTPDauphin60 min
Aug 9, 10:00 AM EDTFlash Flood WarningCTPDauphin60 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.