Alert archive / Pennsylvania / Flash Flood Warnings in 1990

Flash Flood Warning 26, NWS State College, PA

October 23, 1990York County, Pennsylvania

NWS State College, PA issued this flash flood warning at Oct 23, 1990, 10:09 PM EDT for York County, Pennsylvania. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Oct 23, 1990, 10:09 PM EDT (02:09 UTC)
Expired
Oct 24, 1990, 12:15 AM EDT
In force
2 hr
Issued by
NWS State College, PA
Area
Whole counties

County York 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 2.2 hours before the alert went out and 122 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 00:00Z on 1990-10-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 1990-10-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
713 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KHAR 240209 RRA
FFWHAR
PAC109-133-240415-
 
BULLETIN - EBS ACTIVATION REQUESTED
SMALL STREAM AND URBAN FLOOD WARNING
NATIONAL WEATHER SERVICE HARRISBURG PA
1009 PM EDT TUE OCT 23 1990
 
THE NATIONAL WEATHER SERVICE IN HAR EXTENDED THE
SMALL STREAM AND URBAN FLOOD WARNING EFFECTIVE UNTIL 1215 AM EDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN CENTRAL PENNSYLVANIA
          ...SNYDER
IN SOUTH CENTRAL PENNSYLVANIA
          ...YORK
 
AT 1000 PM WEATHER SERVICE RADADELY
SCATTERED MOSTLY LIGHT RAINSHOWERS OVER NORTHCENTRAL PENNSYLVANIA AND
NORTHEASTERN PENNSYLVANIA. REPORTS FROM EMERGENCY MANAGEMENT CENTERS
IN SYNDER AND YORK COUNTIES INDICATE THAT SEVERAL STREETS ARE STILL
FLOODED. ALTHOUGH THE RAIN HAS ENDED IN MOST AREAS...RUNOFFS FROM
TODAYS HEAVY RAINS CONTINUE TO CAUSE MINOR FLOODING ON MANY SMALL
STREAMS AND CREEKS.
 
THE RAINSHOWERS WERE MOVING TOWARDS THE NORTHEAST AT 15 TO 20 MILES AN
HOUR.
 
A SMALL STREAM FLOOD WARNING MEANS THAT SMALL STREAM FLOODING IS
IMMINENT OR IS ALREADY OCCURRING. TAKE NECESSARY SAFETY STEPS OR
PRECAUTIONS AS SOON AS POSSIBLE.
 
TO REPORT FLOODING...CALL THE NEAREST LAW ENFORCEMENT AGENCY OR
EMERGENCY MANAGEMENT OFFICE AND ASK THEM TO RELAY YOUR REPORJT TO THE
NATIONAL WEATHER SERVICE.
 
WSO HAR CRUZ

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 23, 8:55 PM EDTFlash Flood WarningCTPBradford, Lycoming, Sullivan, Tioga3 hr
Oct 23, 10:09 PM EDTFlash Flood WarningCTPSnyder2 hr
Oct 23, 11:35 PM EDTFlash Flood WarningCTPBradford2 hr
Oct 23, 11:45 PM EDTFlash Flood WarningCTPBradford2 hr
Oct 24, 1:47 AM EDTFlash Flood WarningCTPBradford2 hr
Oct 24, 4:02 AM EDTFlash Flood WarningCTPBradford4 hr

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.