Alert archive / Pennsylvania / Flash Flood Warnings in 2009

Flash Flood Warning 21, NWS State College, PA

July 31, 20096 counties in Pennsylvania

NWS State College, PA issued this flash flood warning at Jul 31, 2009, 10:03 AM EDT for 6 counties in Pennsylvania. It was in force for 6 hr. 3 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
Jul 31, 2009, 10:03 AM EDT (14:03 UTC)
Expired
Jul 31, 2009, 4:00 PM EDT
In force
6 hr
Issued by
NWS State College, PA
Area
Storm-based polygon
Flood severity
None

Counties Columbia County, PA, Lycoming County, PA, Montour County, PA, Northumberland County, PA, Sullivan County, PA, Union County, PA

The radar

The State College radar (KCCX), 119 km from the middle of the area, began a volume at 14:04 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
Jul 31, 11:00 AM EDTFLASH FLOOD2 E Muncy, PAA COUPLE STREETS CLOSED IN MUNCY CREEK TOWNSHIP NEAR CLARKSTOWN. APPROX. 3 FEET OF WATER OVER ROADS.
Jul 31, 11:30 AM EDTFLASH FLOODBenton, PAFISHING CREEK AT BANKFULL AND RISING.
Jul 31, 3:05 PM EDTFLASH FLOOD1 N Watsontown, PATRAILER PARK NEAR ROUTE 405 JUST NORTH OF WATSONTOWN INUNDATED BY WATER OF 4-6 FEET DEPTH. AT LEAST 10 TRAILERS FLOODED. ONE PERSON NEEDED TO BE EVACUATED.

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

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 2.1 hours before the alert went out and 255 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, Buffalo Intl Airport, NY at 12:00Z on 2009-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Buffalo Intl Airport, NY at 12:00Z on 2009-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -61 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1394 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
-61 m²/s²
0-3 km storm-relative helicity
-37 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.

000 
WGUS51 KCTP 311403
FFWCTP
PAC037-081-093-097-113-119-312000-
/O.NEW.KCTP.FF.W.0021.090731T1403Z-090731T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1003 AM EDT FRI JUL 31 2009

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHWESTERN MONTOUR COUNTY...
  NORTHWESTERN NORTHUMBERLAND COUNTY...
  NORTHERN COLUMBIA COUNTY...
  SOUTHEASTERN SULLIVAN COUNTY...
  UNION COUNTY...
  SOUTHERN LYCOMING COUNTY...

* UNTIL 400 PM EDT...

* AT 958 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR ESTIMATES   
AND RAIN GAGE REPORTS INDICATED VERY HEAVY RAIN WAS FALLING DUE TO 
REPEATED SHOWERS AND THUNDERSTORMS OVER THE AREA THIS MORNING. MORE 
RAIN IS EXPECTED THROUGH NOON AND EVEN INTO THE AFTERNOON. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
WILLIAMSPORT...MILTON...LEWISBURG...DANVILLE...WATSONTOWN AND  
MONTOURSVILLE. 

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 DONT 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.

IN HILLY TERRAIN THERE ARE HUNDREDS OF LOW WATER CROSSINGS WHICH ARE
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS
FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF
SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

&&

LAT...LON 4132 7631 4114 7632 4085 7735 4106 7713
      4116 7720 4149 7624 4147 7624

$$

FORECASTER: DANGELO
2 follow-up statements
000 
WGUS71 KCTP 311647
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1247 PM EDT FRI JUL 31 2009

PAC037-081-093-097-113-119-312000-
/O.CON.KCTP.FF.W.0021.000000T0000Z-090731T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONTOUR PA-NORTHUMBERLAND PA-COLUMBIA PA-SULLIVAN PA-UNION PA-
LYCOMING PA-
1247 PM EDT FRI JUL 31 2009

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 400 PM EDT FOR 
PARTS OF LYCOMING...UNION...SULLIVAN...COLUMBIA...NORTHUMBERLAND AND 
MONTOUR COUNTIES...

AT 1240 PM EDT...TRAINED WEATHER SPOTTERS AND LOCAL LAW ENFORCEMENT 
OFFICIALS REPORTED FLOODING IN EASTERN LYCOMING COUNTY AND ALONG THE 
COLUMBIA AND SULLIVAN COUNTY BORDER. THE HEAVIEST OF THE RAIN HAS 
ENDED...AND ONLY LIGHT RAIN IS EXPECTED FOR THE REST OF THE 
AFTERNOON. EXPECT LESS THAN A QUARTER OF AN INCH OF ADDITIONAL 
RAINFALL. 

WHILE THE HEAVIEST OF THE RAIN IS OVER...THE STREAMS AND CREEKS IN 
THE AREA CONTINUE TO RISE VERY RAPIDLY. THE STREAMS THAT WOULD BE 
MOST AFFECTED BY THE FLOODING WOULD INCLUDE THE MUNCY CREEK...THE 
WHITE DEER CREEK AND THE FISHING CREEK IN NORTHERN COLUMBIA COUNTY. 
UP TO 3 INCHES OF WATER FELL THIS MORNING IN THOSE STREAM DRAINAGE 
BASINS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

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. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

IN HILLY TERRAIN THERE ARE HUNDREDS OF LOW WATER CROSSINGS WHICH ARE
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS
FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF
SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

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 4132 7631 4114 7632 4085 7735 4106 7713
      4116 7720 4149 7624 4147 7624

$$

FORECASTER: DANGELO
000 
WGUS71 KCTP 312007
FFSCTP

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
407 PM EDT FRI JUL 31 2009

PAC037-081-093-097-113-119-312011-
/O.EXP.KCTP.FF.W.0021.000000T0000Z-090731T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONTOUR PA-NORTHUMBERLAND PA-COLUMBIA PA-SULLIVAN PA-UNION PA-
LYCOMING PA-
407 PM EDT FRI JUL 31 2009

...THE FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHERN LYCOMING...
UNION...SOUTHEASTERN SULLIVAN...NORTHERN COLUMBIA...NORTHWESTERN
NORTHUMBERLAND AND NORTHWESTERN MONTOUR COUNTIES...

LOCAL FLOODING CONTINUES OVER EXTREME NORTHERN NORTHUMBERLAND COUNTY 
FROM EARLIER HEAVY RAINFALL. OTHERWISE...THE WATERS FROM EARLIER 
HEAVY RAINS WILL CONTINUE TO RUN OFF AND RECEDE OVER THE NEXT FEW 
HOURS. 

PLEASE USE CAUTION WHEN DRIVING ON AREA ROADS THIS EVENING...AND BE 
ESPECIALLY ON THE LOOKOUT FOR MUD OR DEBRIS WHICH MAY HAVE BEEN 
DISLODGED BY EARLIER STORM WATER RUNOFF. NO ADDITIONAL HEAVY RAIN IS 
EXPECTED OVER THE WARNING AREA...THEREFORE THE FLASH FLOOD WARNING 
WAS ALLOWED TO EXPIRE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PLEASE REPORT FLOODING 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 4132 7631 4114 7632 4085 7735 4106 7713
      4116 7720 4149 7624 4147 7624

$$

FORECASTER: DEVOIR

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 7:00 AM EDTSpecial Weather StatementCTPMontour30 min
Jul 31, 7:22 AM EDTAreal Flood AdvisoryCTPColumbia, Lycoming, Sullivan3 hr
Jul 31, 7:59 AM EDTAreal Flood AdvisoryCTPMontour, Northumberland, Union3 hr
Jul 31, 8:45 AM EDTAreal Flood AdvisoryCTPCentre, Clearfield2 hr
Jul 31, 2:18 PM EDTSpecial Weather StatementCTPYork42 min

Nearby

Flash Flood Warnings in Pennsylvania, 2009Every flash flood warning in 2009

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.