Alert archive / Pennsylvania / Flash Flood Warnings in 2013

Flash Flood Warning 16, NWS Philadelphia/Mount Holly

June 18, 2013Berks County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 18, 2013, 5:18 PM EDT for Berks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 4 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
Jun 18, 2013, 5:18 PM EDT (21:18 UTC)
Expired
Jun 18, 2013, 9:15 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Berks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 120 km from the middle of the area, began a volume at 21:18 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, 9.3 hours before the alert went out and 143 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, Phillips Aaf/Abe, MD at 12:00Z on 2013-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 811 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, Phillips Aaf/Abe, MD at 12:00Z on 2013-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 square meters per square second.19395878Sfc1 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
811 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
833 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.3

Open this sounding in Storm Lab

The text

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

292 
WGUS51 KPHI 182118
FFWPHI
PAC011-077-095-190115-
/O.NEW.KPHI.FF.W.0016.130618T2118Z-130619T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
518 PM EDT TUE JUN 18 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  BERKS COUNTY...
  LEHIGH COUNTY...
  NORTHAMPTON COUNTY...

* UNTIL 915 PM EDT...

* AT 509 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
  LINE OF SHOWERS AND THUNDERSTORMS JUST SOUTH OF BLUE MOUNTAIN.     
  OVER TWO INCHES OF RAIN HAS FALLEN IN A FEW LOCATIONS ALONG THIS   
  LINE...AND WITH MORE RAIN ON THE WAY...FLASH FLOODING IS EXPECTED  
  WHEREVER THE HEAVIST RAIN HAPPENS TO FALL. THIS LINE OF SHOWERS    
  AND THUNDERSTORMS...EXTENDING FROM THE WESTERN BORDER OF BERKS      
  COUNTY EAST TO THE DELAWARE RIVER...WAS MOVING VERY SLOWLY TO THE  
  SOUTH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.  
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 4058 7603 4065 7599 4078 7568 4086 7529
      4093 7521 4096 7512 4091 7507 4087 7505
      4085 7509 4080 7510 4075 7520 4069 7520
      4068 7518 4061 7520 4043 7551 4044 7553
      4034 7561 4013 7588 4049 7644

$$

FORECASTER: JJM
1 follow-up statement
125 
WGUS71 KPHI 190106
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
906 PM EDT TUE JUN 18 2013

PAC011-077-095-190116-
/O.EXP.KPHI.FF.W.0016.000000T0000Z-130619T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BERKS PA-LEHIGH PA-NORTHAMPTON PA-
906 PM EDT TUE JUN 18 2013

...THE FLASH FLOOD WARNING WILL EXPIRE AT 915 PM EDT FOR
NORTHAMPTON...LEHIGH AND BERKS COUNTIES...

THE WATERS FROM THE EARLIER HEAVY RAINS ARE RECEDING AND NO LONGER
POSE A THREAT TO LIFE OR PROPERTY. THEREFORE...THE FLASH FLOOD
WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 4058 7603 4065 7599 4078 7568 4086 7529
      4093 7521 4096 7512 4091 7507 4087 7505
      4085 7509 4080 7510 4075 7520 4069 7520
      4068 7518 4061 7520 4043 7551 4044 7553
      4034 7561 4013 7588 4049 7644

$$

NIERENBERG

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 18, 10:30 AM EDTSpecial Weather StatementPHIMontgomery, Philadelphia60 min
Jun 18, 12:14 PM EDTAreal Flood AdvisoryPHIBerks, Bucks, Chester, Delaware, Montgomery, Philadelphia3 hr
Jun 18, 12:51 PM EDTFlash Flood WarningPHIChester, Montgomery3 hr
Jun 18, 1:32 PM EDTAreal Flood AdvisoryPHIPhiladelphia3 hr
Jun 18, 2:53 PM EDTAreal Flood WarningPHIChester3 hr
Jun 18, 4:52 PM EDTSpecial Weather StatementPHINorthampton53 min
Jun 18, 5:56 PM EDTAreal Flood AdvisoryPHIBucks4 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2013Every flash flood warning in 2013

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.