Alert archive / Pennsylvania / Flash Flood Warnings in 2011

Flash Flood Warning 21, NWS State College, PA

May 18, 20117 counties in Pennsylvania

NWS State College, PA issued this flash flood warning at May 18, 2011, 5:52 PM EDT for 7 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 outline as issued.

The facts

Issued: May 18, 2011, 5:52 PM EDT (21:52 UTC)
Expired: May 18, 2011, 8:45 PM EDT
In force: 3 hr
Issued by: NWS State College, PA
Area: Storm-based polygon
Flood severity: None

Counties Centre County, PA, Clearfield County, PA, Clinton County, PA, Juniata County, PA, Mifflin County, PA, Snyder County, PA, Union County, PA

The radar

The State College radar (KCCX), 44 km from the middle of the area, began a volume at 21:53 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.9 hours before the alert went out and 186 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: 79 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 561 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 66 m²/s²
0-3 km storm-relative helicity: 169 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

632 
WGUS51 KCTP 182152
FFWCTP
PAC027-033-035-067-087-109-119-190045-
/O.NEW.KCTP.FF.W.0021.110518T2152Z-110519T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
552 PM EDT WED MAY 18 2011

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL CLEARFIELD COUNTY...
  NORTHEASTERN JUNIATA COUNTY...
  NORTHEASTERN MIFFLIN COUNTY...
  WESTERN SNYDER COUNTY...
  SOUTHWESTERN UNION COUNTY...
  CENTRE COUNTY...
  SOUTHWESTERN CLINTON COUNTY...

* UNTIL 845 PM EDT...

* AT 544 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN OVER CENTRE...EAST CENTRAL CLEARFIELD...EXTREME    
  SOUTHWESTERN UNION...NORTHEASTERN JUNIATA...NORTHEASTERN           
  MIFFLIN...SOUTHWESTERN CLINTON AND WESTERN SNYDER COUNTIES.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO BELLEFONTE
  AND STATE COLLEGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. NEVER ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR IN AN
AUTOMOBILE. TURN AROUND DON'T DROWN!

&&

LAT...LON 4063 7695 4060 7703 4059 7717 4055 7718
      4050 7733 4067 7770 4068 7768 4068 7770
      4070 7770 4073 7768 4072 7771 4072 7778
      4074 7782 4073 7786 4096 7838 4136 7785

$$

FORECASTER: CR

The office that day

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

Issued	Product	Office	Counties	Lasted
May 17, 8:17 PM EDT	Tornado Warning	CTP	Franklin, Fulton	28 min
May 17, 8:45 PM EDT	Tornado Warning	CTP	Franklin, Fulton	45 min
May 17, 9:30 PM EDT	Special Weather Statement	CTP	Bedford	30 min
May 18, 2:25 AM EDT	Areal Flood Advisory	CTP	Somerset	3 hr
May 18, 5:13 AM EDT	Areal Flood Advisory	CTP	Bedford, Somerset	3 hr
May 18, 11:51 AM EDT	Special Weather Statement	CTP	Bedford	24 min
May 18, 12:00 PM EDT	Special Weather Statement	CTP	Fulton	30 min
May 18, 12:14 PM EDT	Special Weather Statement	CTP	Somerset	31 min
May 18, 2:51 PM EDT	Special Weather Statement	CTP	York	54 min
May 18, 3:11 PM EDT	Severe Thunderstorm Warning	CTP	York	49 min
May 18, 4:00 PM EDT	Areal Flood Advisory	CTP	Bedford, Somerset	3 hr
May 18, 4:11 PM EDT	Flash Flood Warning	CTP	Somerset	3 hr
May 18, 4:20 PM EDT	Areal Flood Advisory	CTP	Cumberland, Dauphin, York	3 hr
May 18, 4:23 PM EDT	Special Weather Statement	CTP	Juniata, Perry	67 min
May 18, 4:31 PM EDT	Flash Flood Warning	CTP	Adams, Cumberland, Dauphin, Lancaster, Perry, York	4 hr
May 18, 4:47 PM EDT	Special Weather Statement	CTP	Dauphin	43 min
May 18, 5:11 PM EDT	Severe Thunderstorm Warning	CTP	Franklin	64 min
May 18, 5:20 PM EDT	Areal Flood Advisory	CTP	Centre, Juniata, Mifflin, Snyder, Union	3 hr
May 18, 6:31 PM EDT	Flash Flood Warning	CTP	Dauphin, Northumberland, Snyder	3 hr
May 18, 6:32 PM EDT	Special Weather Statement	CTP	Dauphin, Snyder, Union	43 min
May 18, 6:52 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clinton, Lycoming, Snyder, Union	38 min
May 18, 7:47 PM EDT	Areal Flood Advisory	CTP	Cameron, Clearfield, Clinton, Elk, McKean, Potter and 1 more	3 hr
May 18, 7:57 PM EDT	Areal Flood Advisory	CTP	Centre, Clinton, Lycoming, Snyder, Union	3 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.