Alert archive / Pennsylvania / Flash Flood Warnings in 2011

Flash Flood Warning 55, NWS State College, PA

September 10, 2011Cambria County, Clearfield County, Pennsylvania

NWS State College, PA issued this flash flood warning at Sep 10, 2011, 9:02 AM EDT for Cambria County, Clearfield County, Pennsylvania. It was in force for 4 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Sep 10, 2011, 9:02 AM EDT (13:02 UTC)
Expired
Sep 10, 2011, 1:00 PM EDT
In force
4 hr
Issued by
NWS State College, PA
Area
Storm-based polygon
Flood severity
None

Counties Cambria County, PA, Clearfield County, PA

The radar

The State College radar (KCCX), 63 km from the middle of the area, began a volume at 13:04 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.

What was reported inside it

TimeReportWhereRemark
Sep 10, 9:30 AM EDTFLASH FLOODNorthern Cambria, PANUMEROUS ROADS WITH WATER ON THEM
Sep 10, 9:45 AM EDTFLASH FLOODMahaffey, PABRIDGE WASHED OUT ON HANCHAR LANE BELL TWP NEAR RTE 219

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 1.0 hours before the alert went out and 123 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 12:00Z on 2011-09-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 102 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 12:00Z on 2011-09-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -41 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
102 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
552 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-41 m²/s²
0-3 km storm-relative helicity
-2 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.

286 
WGUS51 KCTP 101302
FFWCTP
PAC021-033-101700-
/O.NEW.KCTP.FF.W.0055.110910T1302Z-110910T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
902 AM EDT SAT SEP 10 2011

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN CAMBRIA COUNTY...
  SOUTHWESTERN CLEARFIELD COUNTY...

* UNTIL 100 PM EDT...

* AT 853 AM EDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH
  FLOODING FROM A THUNDERSTORM OVER NORTHERN CAMBRIA AND SOUTHWESTERN
  CLEARFIELD COUNTIES. FLOODING WAS REPORTED ALONG ROUTE 219 NEAR
  MAHAFFEY.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  MAHAFFEY...NORTHERN CAMBRIA...AND IRVONA.

RAIN GAGE REPORTS IN THE AREA INDICATE THAT UP TO AN INCH AND A HALF 
INCHES OF RAIN HAS FALLEN IN THE LAST HOUR.

ADDITIONAL RAINFALL AMOUNTS OF MORE THAN AN INCH ARE POSSIBLE IN THE 
WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. IN HILLY TERRAIN 
THERE ARE HUNDREDS OF SMALL STREAMS WHICH ARE POTENTIALLY DANGEROUS 
IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS FLOODED ROADS OR 
BRIDGES. FIND ALTERNATE ROUTES OVER HIGHER GROUND. IT  TAKES ONLY A 
FEW INCHES OF SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

&&

LAT...LON 4072 7881 4103 7881 4084 7841 4058 7855
      4055 7889

$$

FORECASTER: DANGELO
3 follow-up statements
080 
WGUS51 KCTP 101306 CCA
FFWCTP
PAC021-033-101700-
/O.COR.KCTP.FF.W.0055.110910T1302Z-110910T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING...CORRECTED
NATIONAL WEATHER SERVICE STATE COLLEGE PA
902 AM EDT SAT SEP 10 2011

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN CAMBRIA COUNTY...
  SOUTHWESTERN CLEARFIELD COUNTY...

* UNTIL 100 PM EDT...

* AT 853 AM EDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH
  FLOODING FROM A THUNDERSTORM OVER NORTHERN CAMBRIA AND SOUTHWESTERN
  CLEARFIELD COUNTIES. FLOODING WAS REPORTED ALONG ROUTE 219 NEAR
  MAHAFFEY.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  MAHAFFEY...NORTHERN CAMBRIA...AND IRVONA.

RAIN GAGE REPORTS IN THE AREA INDICATE THAT UP TO AN INCH AND A HALF 
OF RAIN HAS FALLEN IN THE LAST HOUR.

ADDITIONAL RAINFALL AMOUNTS OF MORE THAN AN INCH ARE POSSIBLE IN THE 
WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. IN HILLY TERRAIN 
THERE ARE HUNDREDS OF SMALL STREAMS WHICH ARE POTENTIALLY DANGEROUS 
IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS FLOODED ROADS OR 
BRIDGES. FIND ALTERNATE ROUTES OVER HIGHER GROUND. IT  TAKES ONLY A 
FEW INCHES OF SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

&&

LAT...LON 4072 7881 4103 7881 4084 7841 4058 7855
      4055 7889

$$

FORECASTER: DANGELO
149 
WGUS71 KCTP 101431
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1031 AM EDT SAT SEP 10 2011

PAC021-033-101700-
/O.CON.KCTP.FF.W.0055.000000T0000Z-110910T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CAMBRIA PA-CLEARFIELD PA-
1031 AM EDT SAT SEP 10 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 PM EDT FOR
SOUTHWESTERN CLEARFIELD AND NORTHERN CAMBRIA COUNTIES...

AT 1020 AM EDT...DOPPLER RADAR CONTINUE TO INDICATE THAT VERY HEAVY 
RAIN IS FALLING FROM A STATIONARY THUNDERSTORM OVER NORTHERN CAMBRIA 
AND SOUTHWESTERN CLEARFIELD COUNTIES. THIS RAIN IS PRODUCING FLASH 
FLOODING...ESPECIALLY ALONG THE WEST BRANCH OF THE SUSQUEHANNA RIVER 
AND THE SMALL TRIBUTARIES OF THIS RIVER IN SOUTHWESTERN CLEARFIELD 
COUNTY. UP TO 3 INCHES OF RAIN HAS FALLEN IN THAT AREA THIS MORNING.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
MAHAFFEY...BURNSIDE...WESTOVER...NORTHERN CAMBRIA...CARROLLTOWN... 
HASTINGS...PATTON AND PRINCE GALLITZIN STATE PARK.

ADDITIONAL RAINFALL AMOUNTS OF MORE THAN AN INCHARE POSSIBLE IN THE 
WARNED AREA BEFORE NOON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL 
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. ROAD BEDS MAY BE WASHED OUT 
AND BRIDGES DAMAGED OR UNSTABLE. WHEN ENCOUNTERING FLOODED ROADS 
MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4072 7881 4103 7881 4084 7841 4058 7855
      4055 7889

$$

FORECASTER: DANGELO
621 
WGUS71 KCTP 101656
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1256 PM EDT SAT SEP 10 2011

PAC021-033-101701-
/O.EXP.KCTP.FF.W.0055.000000T0000Z-110910T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CAMBRIA PA-CLEARFIELD PA-
1256 PM EDT SAT SEP 10 2011

...THE FLASH FLOOD WARNING FOR SOUTHWESTERN CLEARFIELD AND NORTHERN 
CAMBRIA COUNTIES WILL BE ALLOWED TO EXPIRE...

THE EARLIER HEAVY RAINS HAVE ENDED...AND THERE ARE NO NEW REPORTS OF 
FLOODING. THE WEST BRANCH AND STREAMS LEADING TO IT MAY STILL BE 
RUNNING VERY HIGH...BUT THE THREAT FOR ADDITIONAL FLOODING IS LOW.  
THEREFORE...THE FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE.

PLEASE CONTINUE TO HEED ALL ROAD CLOSURES. MOST FLOOD DEATHS OCCUR 
IN AUTOMOBILES...USUALLY FROM PEOPLE DRIVING INTO FLOODS.  

ADDITIONAL SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND 
EVENING. IF THESE ARE EXPECTED TO PRODUCE HEAVY RAIN AGAIN IN THIS 
AREA...MORE STATEMENTS OR FLOOD WARNINGS MAY BE NECESSARY.

LAT...LON 4072 7881 4103 7881 4084 7841 4058 7855
      4055 7889

$$

FORECASTER: DANGELO

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 9, 8:19 PM EDTFlash Flood WarningCTPBlair, Cambria, Centre, Clearfield, Huntingdon, Juniata and 2 more3 hr
Sep 9, 8:31 PM EDTSpecial Weather StatementCTPJuniata, Mifflin, Perry59 min
Sep 9, 9:32 PM EDTSpecial Weather StatementCTPJuniata, Perry58 min
Sep 9, 10:08 PM EDTFlash Flood WarningCTPJuniata, Mifflin, Perry, Snyder3 hr
Sep 9, 10:41 PM EDTRiver Flood WarningCTPBlair, Huntingdon15 hr
Sep 9, 10:41 PM EDTRiver Flood WarningCTPBlair, Huntingdon6 hr
Sep 9, 10:41 PM EDTRiver Flood WarningCTPPerry15 hr
Sep 9, 11:09 PM EDTFlash Flood WarningCTPDauphin, Montour, Northumberland, Schuylkill, Snyder, Union4 hr
Sep 9, 11:42 PM EDTAreal Flood AdvisoryCTPElk78 min
Sep 10, 12:32 AM EDTFlash Flood Warning EmergencyCTPColumbia, Lycoming, Montour, Northumberland, Schuylkill5 hr
Sep 10, 12:57 AM EDTAreal Flood WarningCTPJuniata, Mifflin, Perry, Snyder6 hr
Sep 10, 1:14 AM EDTSpecial Weather StatementCTPWarren46 min
Sep 10, 4:01 AM EDTAreal Flood AdvisoryCTPElk, McKean, Warren3 hr
Sep 10, 6:51 AM EDTAreal Flood AdvisoryCTPCambria, Cameron, Clearfield, Elk, McKean, Warren3 hr
Sep 10, 4:40 PM EDTAreal Flood AdvisoryCTPAdams, Cumberland, Franklin, Huntingdon, Juniata, Mifflin and 2 more3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2011Every flash flood warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.