Alert archive / Pennsylvania / Flash Flood Warnings in 2012

Flash Flood Warning 17, NWS State College, PA

August 26, 2012York County, Pennsylvania

NWS State College, PA issued this flash flood warning at Aug 26, 2012, 3:46 PM EDT for York 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 outline as issued.

The facts

Issued
Aug 26, 2012, 3:46 PM EDT (19:46 UTC)
Expired
Aug 26, 2012, 6:45 PM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Storm-based polygon
Flood severity
None

County York County, PA

The radar

The Sterling radar (KLWX), 113 km from the middle of the area, began a volume at 19:45 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.8 hours before the alert went out and 112 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 2012-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 926 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, Washington/Dulle, VA at 12:00Z on 2012-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 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
926 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
504 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

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

632 
WGUS51 KCTP 261946
FFWCTP
PAC133-262245-
/O.NEW.KCTP.FF.W.0017.120826T1946Z-120826T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
346 PM EDT SUN AUG 26 2012

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTH CENTRAL YORK COUNTY...

* UNTIL 645 PM EDT...

* AT 342 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER SOUTH CENTRAL YORK  
  COUNTY. RAINFALL IN EXCESS OF 2 INCHES HAS ALREADY OCCURRED NEAR
  THE MARYLAND BORDER...WITH AN ADDITIONAL ONE TO TWO INCHES
  POSSIBLE OVER THE NEXT ONE TO TWO HOURS. EXCESSIVE RUNOFF FROM THE 
  ADDITIONAL RAINFALL WILL PRODUCE FLASH FLOODING SHORTLY.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO NEW
  FREEDOM...SHREWSBURY...GLEN ROCK...SEVEN VALLEYS...DALLASTOWN...
  RED LION AND SPRY.

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!

PLEASE REPORT FLOODING...HAIL OR WIND DAMAGE TO THE NATIONAL WEATHER
SERVICE BY CALLING TOLL FREE...1 8 7 7 6 3 3 6 7 7 2.

&&

LAT...LON 3978 7681 3984 7681 3992 7678 3991 7660
      3980 7659 3972 7659 3971 7682

$$

FORECASTER: DEVOIR/STEINBUGL
2 follow-up statements
452 
WGUS71 KCTP 262140
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
540 PM EDT SUN AUG 26 2012

PAC133-262245-
/O.CON.KCTP.FF.W.0017.000000T0000Z-120826T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
YORK PA-
540 PM EDT SUN AUG 26 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM EDT FOR SOUTH
CENTRAL YORK COUNTY...

AT 538 PM EDT...DOPPLER RADAR ESTIMATES CONTINUES TO INDICATE 
SHOWERS OVER THE WARNING AREA...WITH SOME HEAVIER SHOWERS EXPECTED 
TO TRACK NORTHWARD FROM MARYLAND DURING THE NEXT HOUR. NO FLOODING 
HAS OCCURRED SO FAR...BUT RUNOFF FROM EARLIER AND ADDITIONAL 
RAINFALL WILL MAINTAIN THE THREAT OF FLASH FLOODING. THEREFORE THE 
FLASH FLOOD WARNING WILL CONTINUE THROUGH 645 PM EDT.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO DALLASTOWN...
RED LION AND SPRY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

PLEASE REPORT FLOODING...HAIL OR WIND DAMAGE BY CALLING YOUR LOCAL
LAW ENFORCEMENT OFFICIALS OR BY CALLING THE NATIONAL WEATHER SERVICE
TOLL FREE AT...1 8 7 7 6 3 3 6 7 7 2.

&&

LAT...LON 3978 7681 3984 7681 3992 7678 3991 7660
      3980 7659 3972 7659 3971 7682

$$

FORECASTER: DEVOIR
906 
WGUS71 KCTP 262243
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
643 PM EDT SUN AUG 26 2012

PAC133-262253-
/O.EXP.KCTP.FF.W.0017.000000T0000Z-120826T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
YORK PA-
643 PM EDT SUN AUG 26 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 645 PM EDT FOR SOUTH
CENTRAL YORK COUNTY...

RUNOFF FROM EARLIER HEAVY RAINFALL NO LONGER POSES A THREAT TO LIFE 
OR PROPERTY. THEREFORE...THE FLASH FLOOD WARNING WILL BE ALLOWED TO 
EXPIRE.

LAT...LON 3978 7681 3984 7681 3992 7678 3991 7660
      3980 7659 3972 7659 3971 7682

$$

FORECASTER: DEVOIR

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 26, 2:01 PM EDTTornado WarningCTPFranklin, Fulton29 min
Aug 26, 2:30 PM EDTTornado WarningCTPFranklin, Huntingdon17 min
Aug 26, 2:51 PM EDTSpecial Weather StatementCTPFranklin24 min
Aug 26, 3:19 PM EDTFlash Flood WatchCTPAdams, Cumberland, Dauphin, Franklin, Fulton, Lancaster and 3 more4 hr
Aug 26, 3:36 PM EDTAreal Flood AdvisoryCTPAdams, Cumberland, Franklin3 hr
Aug 26, 4:03 PM EDTSpecial Weather StatementCTPCumberland, Perry57 min
Aug 26, 4:21 PM EDTFlash Flood WarningCTPAdams, Cumberland, Franklin, Perry3 hr
Aug 26, 4:23 PM EDTSevere Thunderstorm WarningCTPCumberland, Juniata, Perry67 min
Aug 26, 4:47 PM EDTSpecial Weather StatementCTPDauphin, Lebanon43 min
Aug 26, 5:22 PM EDTSpecial Weather StatementCTPCentre, Clinton38 min
Aug 26, 5:29 PM EDTSpecial Weather StatementCTPNorthumberland, Snyder, Union31 min
Aug 26, 5:42 PM EDTSpecial Weather StatementCTPClinton, Lycoming33 min
Aug 26, 6:17 PM EDTSpecial Weather StatementCTPLycoming73 min

Nearby

Flash Flood Warnings in Pennsylvania, 2012Every flash flood warning in 2012

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.