Alert archive / Pennsylvania / Flash Flood Warnings in 2004

Flash Flood Warning 3, NWS State College, PA

May 10, 2004York County, Pennsylvania

NWS State College, PA issued this flash flood warning at May 10, 2004, 12:09 AM EDT for York County, Pennsylvania. It was in force for 3 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 10, 2004, 12:09 AM EDT (04:09 UTC)
Expired
May 10, 2004, 3:15 AM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Counties, with a storm outline in the text

County York County, PA

The radar

The Sterling radar (KLWX), 129 km from the middle of the area, began a volume at 04:09 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 4.2 hours before the alert went out and 128 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 2004-05-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 629 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 00:00Z on 2004-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 square meters per square second.1939Sfc1 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
629 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
1932 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
151 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KCTP 100413
FFWCTP
PAC133-100715-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1209 AM EDT MON MAY 10 2004

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  YORK COUNTY IN SOUTH CENTRAL PENNSYLVANIA

* UNTIL 315 AM EDT.

* AT 1204 AM EDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED          
  FLOODING ALREADY OCCURRING IN AREAS SOUTHEAST OF YORK.

SLOW MOVING THUNDERSTORMS ARE PRODUCING TORRENTIAL RAINFALL IN THE 
WARNED AREA. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH 
FLOODING...ESPECIALLY NEAR RED LION AND DALLASTOWN WHERE THE 
HEAVIEST RAIN HAS ALREADY OCCURRED.

RADAR ESTIMATED THAT RAINFALL OF 4 TO 5 INCHES HAS FALLEN IN THIS 
AREA OVER THE PAST SEVERAL HOURS...WITH AN ADDITIONAL INCH POSSIBLE 
OVER THE NEXT HOUR OR TWO.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS.

LAT...LON 4011 7671 3974 7630 3975 7668 4007 7700

$$

KF

The office that day

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

IssuedProductOfficeCountiesLasted
May 9, 9:20 PM EDTFlash Flood WarningCTPYork3 hr
May 10, 5:31 PM EDTSevere Thunderstorm WarningCTPWarren59 min
May 10, 6:54 PM EDTSevere Thunderstorm WarningCTPMcKean66 min
May 10, 7:04 PM EDTSevere Thunderstorm WarningCTPElk56 min
May 10, 7:38 PM EDTSevere Thunderstorm WarningCTPWarren37 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.