Alert archive / Pennsylvania / Flash Flood Warnings in 2011

Flash Flood Warning 17, NWS State College, PA

May 13, 2011Somerset County, Pennsylvania

NWS State College, PA issued this flash flood warning at May 13, 2011, 2:24 PM EDT for Somerset County, Pennsylvania. It was in force for 2 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 13, 2011, 2:24 PM EDT (18:24 UTC)
Expired: May 13, 2011, 4:31 PM EDT
In force: 2 hr
Issued by: NWS State College, PA
Area: Storm-based polygon
Flood severity: None

County Somerset County, PA

The radar

The Pittsburgh radar (KPBZ), 104 km from the middle of the area, began a volume at 18:24 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 12:00Z, 6.4 hours before the alert went out and 88 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 205 J/kg
Mixed-layer CIN: -131 J/kg
Mixed-layer LCL: 1018 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 68 m²/s²
0-3 km storm-relative helicity: 67 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.

412 
WGUS51 KCTP 131824
FFWCTP
PAC111-132215-
/O.NEW.KCTP.FF.W.0017.110513T1824Z-110513T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
224 PM EDT FRI MAY 13 2011

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WESTERN SOMERSET COUNTY...

* UNTIL 615 PM EDT...

* AT 216 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM AN AREA OF NEARLY STATIONARY THUNDERSTORMS 
  OVER WESTERN SOMERSET COUNTY. DOPPLER RADAR ESTIMATED THAT OVER 
  3 INCHES OF RAIN HAS FALLEN IN THE PAST 90 MINUTES ACROSS PARTS 
  OF THE WARNED AREA. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  CASSELMAN...CONFLUENCE...ROCKWOOD AND SEVEN SPRINGS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS OCCURRING OR IS IMMINENT. MOST FLOOD RELATED 
DEATHS OCCUR IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED 
BRIDGES...DIPS...OR LOW WATER CROSSINGS. TURN AROUND...DON'T DROWN! 
NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO 
ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.

&&

LAT...LON 3979 7936 3982 7937 3985 7942 3987 7942
      3993 7939 4010 7926 4013 7921 4012 7919
      4014 7917 4008 7905 4001 7909 3988 7912
      3978 7921

$$

FORECASTER: LAMBERT/TYBURSKI/GARTNER

1 follow-up statement

291 
WGUS71 KCTP 132031
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
431 PM EDT FRI MAY 13 2011

PAC111-132040-
/O.CAN.KCTP.FF.W.0017.000000T0000Z-110513T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SOMERSET PA-
431 PM EDT FRI MAY 13 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR WESTERN SOMERSET
COUNTY...

THE WATERS FROM THE EARLIER HEAVY RAINS ARE RECEDING AND FLOOD WATERS
NO LONGER POSE A THREAT TO LIFE OR PROPERTY. THEREFORE...THE FLASH
FLOOD WARNING HAS BEEN CANCELLED.


LAT...LON 3979 7936 3982 7937 3985 7942 3987 7942
      3993 7939 4010 7926 4013 7921 4012 7919
      4014 7917 4008 7905 4001 7909 3988 7912
      3978 7921

$$

FORECASTER: KF

The office that day

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

Issued	Product	Office	Counties	Lasted
May 13, 11:34 AM EDT	Special Weather Statement	CTP	Cambria	26 min
May 13, 1:42 PM EDT	Special Weather Statement	CTP	Somerset	33 min
May 13, 2:02 PM EDT	Areal Flood Advisory	CTP	Somerset	3 hr
May 13, 4:28 PM EDT	Special Weather Statement	CTP	Warren	2 hr
May 13, 5:38 PM EDT	Special Weather Statement	CTP	McKean	112 min
May 13, 7:26 PM EDT	Special Weather Statement	CTP	Cameron, Elk, Potter, Tioga	2 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2011 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.