Alert archive / Pennsylvania / Flash Flood Warnings in 2001

Flash Flood Warning 41, NWS State College, PA

September 24, 200110 counties in Pennsylvania

NWS State College, PA issued this flash flood warning at Sep 24, 2001, 7:36 PM EDT for 10 counties in 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 counties it named.

The facts

Issued
Sep 24, 2001, 7:36 PM EDT (23:36 UTC)
Expired
Sep 24, 2001, 10:30 PM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Whole counties

Counties Columbia County, PA, Dauphin County, PA, Lebanon County, PA, Lycoming County, PA, Montour County, PA, Northumberland County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Union County, PA

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 11.6 hours before the alert went out and 166 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, Phillips Aaf/Abe, MD at 12:00Z on 2001-09-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 432 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, Phillips Aaf/Abe, MD at 12:00Z on 2001-09-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 square meters per square second.19395878Sfc1 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
432 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
541 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.4

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KCTP 242339
FFWCTP
PAC037-043-075-081-093-097-107-109-113-119-250230-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
736 PM EDT MON SEP 24 2001

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SULLIVAN COUNTY IN PENNSYLVANIA
  COLUMBIA COUNTY IN PENNSYLVANIA
  NORTHUMBERLAND COUNTY IN PENNSYLVANIA
  MONTOUR COUNTY IN PENNSYLVANIA
  UNION COUNTY IN PENNSYLVANIA
  SCHUYLKILL COUNTY IN PENNSYLVANIA
  SNYDER COUNTY IN PENNSYLVANIA
  DAUPHIN COUNTY IN PENNSYLVANIA
  LEBANON COUNTY IN PENNSYLVANIA
  LYCOMING COUNTY IN PENNSYLVANIA

* UNTIL 1030 PM EDT.

* AT 733 PM...DOPPLER RADAR CONTINUES TO SHOW A LARGE AREA OF 
THUNDERSTORMS...SOME WITH TORRENTIAL DOWNPOURS...MOVING FROM SOUTH 
TO NORTH OVER THE SUSQUEHANNA VALLEY.

EXPECT THE THUNDERSTORMS AND TORRENTIAL RAIN TO CAUSE LOCALIZED 
FLASH FLOODING IN THE WARNED AREAS. URBAN AND POOR DRAINAGE AREAS 
WILL BE ESPECIALLY PRONE TO THE FLASH FLOODING.

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 4156 7629 4078 7587 4032 7619 4019 7677
          4041 7699 4107 7721 4151 7751

LA CORTE

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 24, 6:22 PM EDTSevere Thunderstorm WarningCTPAdams, York53 min
Sep 24, 6:53 PM EDTTornado WarningCTPYork67 min
Sep 24, 7:16 PM EDTFlash Flood WarningCTPAdams, York3 hr
Sep 24, 7:57 PM EDTSevere Thunderstorm WarningCTPLancaster, York63 min

Nearby

Flash Flood Warnings in Pennsylvania, 2001Every flash flood warning in 2001

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.