Alert archive / Pennsylvania / Flash Flood Warnings in 2001

Flash Flood Warning 35, NWS State College, PA

August 11, 2001Lancaster County, Pennsylvania

NWS State College, PA issued this flash flood warning at Aug 11, 2001, 12:45 PM EDT for Lancaster 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 counties it named.

The facts

Issued
Aug 11, 2001, 12:45 PM EDT (16:45 UTC)
Expired
Aug 11, 2001, 3:45 PM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Whole counties

County Lancaster County, PA

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 4.8 hours before the alert went out and 157 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 2001-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 725 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 2001-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 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
725 J/kg
Mixed-layer CIN
-68 J/kg
Mixed-layer LCL
880 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
19 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 
WGUS51 KCTP 111653
FFWCTP
PAC071-111945-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1245 PM EDT SAT AUG 11 2001

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  LANCASTER COUNTY IN PENNSYLVANIA

* UNTIL 345 PM EDT.

* AT 1240 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
CLUSTER OF SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL OVER 
WESTERN LANCASTER COUNTY...FROM MAYTOWN TO MT. JOY.

DOPPLER RADAR ESTIMATES THAT MORE THAN 2 INCHES OF RAIN HAS FALLEN 
IN THIS AREA IN THE LAST HOUR....WITH SOME AMOUNTS OVER 3 INCHES 
ESTIMATED IN THE LAST 3 HOURS. RUNOFF FROM THIS EXCESSIVE RAINFALL 
WILL CAUSE FLASH FLOODING OVER PORTIONS OF WESTERN LANCASTER COUNTY. 
EXPECT TRAVEL PROBLEMS DUE TO PONDING OF WATER ON THE ROADWAYS...AS 
WELL AS REDUCED VISIBILITIES IN THE HEAVY RAIN...ALONG ROUTES 
30...230 AND 283.

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 4013 7671 3994 7644 4013 7625 4031 7619

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.