Alert archive / Pennsylvania / Flash Flood Warnings in 2004

Flash Flood Warning 7, NWS State College, PA

May 20, 2004Clearfield County, Pennsylvania

NWS State College, PA issued this flash flood warning at May 20, 2004, 11:48 PM EDT for Clearfield County, Pennsylvania. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 20, 2004, 11:48 PM EDT (03:48 UTC)
Expired
May 21, 2004, 5:45 AM EDT
In force
6 hr
Issued by
NWS State College, PA
Area
Counties, with a storm outline in the text

County Clearfield County, PA

The radar

The State College radar (KCCX), 60 km from the middle of the area, began a volume at 03:51 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 00:00Z, 3.8 hours before the alert went out and 143 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 2004-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1205 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Pittsburgh, PA at 00:00Z on 2004-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 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
1205 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
1103 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
267 m²/s²
Significant tornado parameter
0.9
Supercell composite
7.9

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KCTP 210355
FFWCTP
PAC033-210945-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1148 PM EDT THU MAY 20 2004

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CLEARFIELD COUNTY IN CENTRAL PENNSYLVANIA

* UNTIL 545 AM EDT.

* AT 1140 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  CLUSTER OF THUNDERSTORMS WITH VERY HEAVY RAINFALL OVER WEST
  CENTRAL CLEARFIELD COUNTY. 

SLOW MOVING THUNDERSTORMS WILL PRODUCE TORRENTIAL RAINFALL IN THE 
WARNED AREA...WITH RAINFALL RATES OF 1.5 INCHES PER HOUR OR GREATER 
EXPECTED. MINOR STREET FLOODING HAS BEEN REPORTED BY LOCAL LAW 
ENFORCEMENT IN DUBOIS. 

ADDITIONAL THUNDERSTORMS WITH TORRENTIAL RAINFALL WILL TRACK ALONG 
THE SAME PATH. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL LIKELY CAUSE 
FLASH FLOODING IN PARTS OF WEST CENTRAL CLEARFIELD COUNTY THROUGH 
THE EARLY MORNING HOURS. SOME TOWNS INCLUDED IN THE FLASH FLOOD 
WARNING AREA INCLUDE DUBOIS...TREASURE LAKE...ROCKTON AND FALLS 
CREEK. 

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED. MOVE TO
HIGHER GROUND. BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO 
RECOGNIZE THE DANGERS OF FLOODS AND FLASH FLOODS.


LAT...LON 4114 7856 4094 7856 4106 7881 4116 7881
          4122 7873

$$

DEVOIR/LAMBERT/LIPTON/RXR
1 follow-up statement
000 
WGUS71 KCTP 210704
FFSCTP
PAC033-211000-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
255 AM EDT FRI MAY 21 2004


...A FLASH FLOOD WARNING CONTINUES FOR CLEARFIELD COUNTY UNTIL 545 AM
EDT...

SEVERAL CLUSTERS OF THUNDERSTORMS CONTAINING VERY HEAVY RAIN WILL 
AFFECT CLEARFIELD COUNTY THROUGH 5 AM...PRODUCING ADDITIONAL 
RAINFALL AMOUNTS OF 1 TO 2 INCHES. THIS ADDITIONAL HEAVY 
RAIN...COMBINED WITH HEAVY RAINFALL FROM EARLIER 
THUNDERSTORMS...WILL LIKELY LEAD TO FLOODING FROM RUNOFF. 
THE NORTHWEST PART OF CLEARFIELD COUNTY WILL BE PARTICULARLY 
VULNERABLE TO FLOODING...ESPECIALLY FROM NEAR DUBOIS TO AROUND 
ROCKTON.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED. MOVE TO
HIGHER GROUND.

LAT...LON 4116 7877 4076 7880 4076 7841 4113 7814
          4122 7811 4123 7849 4124 7863

$$

KL/BL

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 10:51 PM EDTSevere Thunderstorm WarningCTPClearfield54 min
May 20, 11:18 PM EDTSevere Thunderstorm WarningCTPWarren72 min
May 21, 4:54 AM EDTFlash Flood WarningCTPClearfield4 hr
May 21, 5:19 AM EDTFlash Flood WarningCTPWarren4 hr
May 21, 6:29 AM EDTSevere Thunderstorm WarningCTPCambria, Somerset61 min
May 21, 6:31 AM EDTFlash Flood WarningCTPBlair4 hr
May 21, 7:11 AM EDTSevere Thunderstorm WarningCTPBedford, Blair49 min
May 21, 6:55 PM EDTSevere Thunderstorm WarningCTPCambria, Clearfield, Somerset80 min
May 21, 7:30 PM EDTSevere Thunderstorm WarningCTPBedford, Blair60 min

Nearby

Flash Flood Warnings in Pennsylvania, 2004Every flash flood warning in 2004

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; radar from the NEXRAD Level II archive.