Alert archive / Pennsylvania / Flash Flood Warnings in 2011

Flash Flood Warning 64, NWS State College, PA

September 23, 2011Lancaster County, Pennsylvania

NWS State College, PA issued this flash flood warning at Sep 23, 2011, 6:16 PM EDT for Lancaster County, Pennsylvania. It was in force for 3 hr. 1 report 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 23, 2011, 6:16 PM EDT (22:16 UTC)
Expired: Sep 23, 2011, 9:15 PM EDT
In force: 3 hr
Issued by: NWS State College, PA
Area: Storm-based polygon
Flood severity: None

County Lancaster County, PA

The radar

The Dover AFB radar (KDOX), 134 km from the middle of the area, began a volume at 22:16 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

Time	Report	Where	Remark
Sep 23, 7:21 PM EDT	FLASH FLOOD	1 S Wrightsdale, PA	WATER RESCUE FROM HOUSE SURROUNDED BY WATER. SEVERAL ROADWAYS FLOODED IN FULTON TOWNSHIP..

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.3 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-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: 709 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 443 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 54 m²/s²
0-3 km storm-relative helicity: 38 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

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

666 
WGUS51 KCTP 232216
FFWCTP
PAC071-240115-
/O.NEW.KCTP.FF.W.0064.110923T2216Z-110924T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
616 PM EDT FRI SEP 23 2011

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN LANCASTER COUNTY...

* UNTIL 915 PM EDT...

* AT 610 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  AN AREA OF HEAVY RAIN ACROSS EASTERN LANCASTER COUNTY. RAINFALL 
  AMOUNTS OF 1 TO 1.5 INCHES HAVE OCCURRED ACROSS EXTREME EASTERN 
  LANCASTER COUNTY DURING THE PAST SEVERAL HOURS. PERIODS OF 
  MODERATE TO HEAVY RAIN WILL PERSIST THROUGH 8 PM...AND AN
  ADDITIONAL 1 INCH OF RAIN IS LIKELY EARLY THIS EVENING ACROSS 
  MUCH OF THE WARNED AREA.   

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LEOLA...NEW
  HOLLAND...WILLOW STREET...PARADISE...WAKEFIELD...GAP... 
  CHRISTIANA...AND CHURCHTOWN.   

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3978 7628 3986 7637 4026 7606 4026 7605
      4014 7588 4011 7593 4003 7593 3996 7599
      3988 7598 3984 7602 3983 7601 3977 7606
      3972 7610 3972 7624

$$

FORECASTER: LAMBERT

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 23, 1:15 AM EDT	Dense Fog Advisory	CTP	Adams, Bedford, Blair, Cameron, Centre, Clearfield and 24 more	9 hr
Sep 23, 9:53 AM EDT	Flash Flood Watch	CTP	Adams, Columbia, Cumberland, Dauphin, Juniata, Lancaster and 10 more	16 hr
Sep 23, 11:39 AM EDT	Areal Flood Advisory	CTP	Adams, Columbia, Cumberland, Dauphin, Franklin, Lancaster and 5 more	6 hr
Sep 23, 11:46 AM EDT	Flash Flood Warning	CTP	Adams	6 hr
Sep 23, 1:46 PM EDT	Flash Flood Warning	CTP	Schuylkill	3 hr
Sep 23, 1:52 PM EDT	Areal Flood Advisory	CTP	Columbia, Cumberland, Dauphin, Juniata, Montour, Northumberland and 4 more	6 hr
Sep 23, 2:42 PM EDT	Flash Flood Warning	CTP	Dauphin	3 hr
Sep 23, 4:04 PM EDT	Flash Flood Warning	CTP	Cumberland, York	5 hr
Sep 23, 5:35 PM EDT	Areal Flood Warning	CTP	Adams	6 hr
Sep 23, 6:48 PM EDT	River Flood Warning	CTP	Cumberland, York	7 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.