Alert archive / Pennsylvania / Flash Flood Warnings in 2003

Flash Flood Warning 33, NWS Philadelphia/Mount Holly

August 11, 2003Bucks County, Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 11, 2003, 3:16 AM EDT for Bucks County, Lehigh County, Pennsylvania. It was in force for 119 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 11, 2003, 3:16 AM EDT (07:16 UTC)
Expired: Aug 11, 2003, 5:15 AM EDT
In force: 119 min
Issued by: NWS Philadelphia/Mount Holly
Area: Whole counties

Counties Bucks County, PA, Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 99 km from the middle of the area, began a volume at 07:20 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

Brookhaven, NY (KOKX), launched 00:00Z, 7.3 hours before the alert went out and 214 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: 511 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 557 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 53 m²/s²
0-3 km storm-relative helicity: 57 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 KPHI 110719
FFWPHI
PAC017-077-110915-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
316 AM EDT MON AUG 11 2003

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN LEHIGH COUNTY IN EASTERN PENNSYLVANIA
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA

* UNTIL 515 AM EDT.

* AT 314 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
HEAVY SHOWERS MOVING SLOWLY NORTH ACROSS NORTHWESTERN BUCKS AND
SOUTHEASTERN LEHIGH COUNTIES.  RAINFALL FROM THESE STORMS MAY
EXCEED 2 INCHES.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED ACT
QUICKLY. MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY
IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. 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. VEHICLES
CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHER
GROUND.

FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER
RADIO...YOUR LOCAL RADIO OR TELEVISION STATION...OR YOUR CABLE
TELEVISION OUTLET.

$$

LAT...LON 4048 7528 4037 7538 4049 7554 4063 7544

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 2:01 AM EDT	Flash Flood Warning	PHI	Montgomery	3 hr
Aug 11, 6:07 PM EDT	Flash Flood Warning	PHI	Northampton	3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2003 Every flash flood warning in 2003

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.