Alert archive / Pennsylvania / Flash Flood Warnings in 2014

Flash Flood Warning 32, NWS Philadelphia/Mount Holly

July 14, 2014Bucks County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 14, 2014, 5:31 PM EDT for Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 3 hr. 2 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 14, 2014, 5:31 PM EDT (21:31 UTC)
Expired: Jul 14, 2014, 8:30 PM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Bucks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 113 km from the middle of the area, began a volume at 21:31 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
Jul 14, 5:45 PM EDT	FLASH FLOOD	Salisbury Twp, PA	NUMEROUS ROADS FLOODED AND SOME WASHED OUT... RESULTING IN CLOSURES. WATER INTO THE FIRST FLOOR OF BUILDINGS.
Jul 14, 5:48 PM EDT	FLASH FLOOD	Allentown, PA	SEVERAL ROADS FLOODED IN AND AROUND THE ALLENTOWN AREA. INTERSECTION OF WALBERT AVE AND CEDAR CREST BLVD FLOODED IN NEARBY SOUTH WHITEHALL TWP. LEHIGH STREET FLOODED IN EMMAUS. ROADS ALSO FLOODED IN UPPER SAUCON TWP. VEHICLES STALLED OUT IN THESE LOCATIONS ATT

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

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.5 hours before the alert went out and 160 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: 483 J/kg
Mixed-layer CIN: -85 J/kg
Mixed-layer LCL: 844 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 125 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.

122 
WGUS51 KPHI 142131
FFWPHI
PAC017-077-095-150030-
/O.NEW.KPHI.FF.W.0032.140714T2131Z-140715T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
531 PM EDT MON JUL 14 2014

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF ALLENTOWN...
  NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF EASTON...
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 830 PM EDT

* AT 526 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  HEAVY RAIN CAPABLE OF PRODUCING FLASH FLOODING OVER PORTIONS OF    
  THE WARNED AREA. RAINFALL RATES UP TO TWO INCHES PER HOUR ARE      
  POSSIBLE AS THIS AREA OF PRECIPITATION MOVES NORTHEAST AT AROUND   
  15 MPH. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO            
  ALLENTOWN...BETHLEHEM...EASTON...SCHNECKSVILLE...SLATINGTON...PEN  
  AGYL...NORTHAMPTON...NEW TRIPOLI...NAZARETH...FORKS...AND EMERALD.
  
PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES AS 
WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

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.

&&

LAT...LON 4086 7505 4085 7509 4082 7509 4078 7513
      4078 7517 4075 7520 4073 7518 4069 7520
      4067 7518 4066 7520 4058 7520 4056 7516
      4038 7540 4068 7589 4078 7568 4086 7529
      4093 7521 4096 7512

$$

JJM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 13, 8:04 PM EDT	Special Weather Statement	PHI	Carbon	71 min
Jul 13, 8:33 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Lehigh, Monroe, Northampton	57 min
Jul 13, 8:41 PM EDT	Special Weather Statement	PHI	Berks, Lehigh	2 hr
Jul 13, 9:04 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	56 min
Jul 13, 9:16 PM EDT	Special Weather Statement	PHI	Northampton	89 min
Jul 13, 9:33 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Lehigh, Monroe, Northampton	57 min
Jul 13, 9:44 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Northampton	46 min
Jul 13, 10:06 PM EDT	Special Weather Statement	PHI	Berks	54 min
Jul 13, 10:14 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	46 min
Jul 13, 10:41 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	2 hr
Jul 13, 10:48 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	37 min
Jul 13, 11:07 PM EDT	Special Weather Statement	PHI	Bucks, Montgomery	38 min
Jul 13, 11:21 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	54 min
Jul 13, 11:27 PM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery	2 hr
Jul 14, 3:54 AM EDT	Flash Flood Watch	PHI	Berks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more	45 hr
Jul 14, 3:43 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery	62 min
Jul 14, 4:38 PM EDT	Areal Flood Advisory	PHI	Chester	3 hr
Jul 14, 4:50 PM EDT	Areal Flood Advisory	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	4 hr
Jul 14, 5:06 PM EDT	Special Weather Statement	PHI	Bucks	54 min
Jul 14, 5:09 PM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery	3 hr
Jul 14, 5:16 PM EDT	Special Weather Statement	PHI	Lehigh, Northampton	59 min
Jul 14, 7:39 PM EDT	Areal Flood Advisory	PHI	Bucks, Delaware, Montgomery, Philadelphia	3 hr
Jul 14, 7:53 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	67 min

Nearby

Flash Flood Warnings in Pennsylvania, 2014 Every flash flood warning in 2014

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.