Alert archive / Pennsylvania / Flash Flood Warnings in 2000

Flash Flood Warning 7, NWS Philadelphia/Mount Holly

March 23, 20005 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Mar 23, 2000, 10:40 AM EST for 5 counties in Pennsylvania. It was in force for 15 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
Mar 23, 2000, 10:40 AM EST (15:40 UTC)
Expired
Mar 23, 2000, 10:55 AM EST
In force
15 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

Counties Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 82 km from the middle of the area, began a volume at 15:43 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, 3.7 hours before the alert went out and 94 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 2000-03-23Temperature 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°0°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 2000-03-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
874 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
48 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 231540
FFWPHI
PAC017-029-045-091-101-231555-

FLASH FLOOD WARNING!! THIS IS ONLY A TEST!!!
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1040 AM EST THU MAR 23 2000

        *** THIS MESSAGE IS FOR TEST PURPOSES ONLY ***
    * NO SEVERE WEATHER IS OCCURRING IN THE MENTIONED AREA *

...TEST...TEST...TEST...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* DRILL FLASH FLOOD WARNING FOR...
  CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA
  MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA
  BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA

* UNTIL 1055 AM EST.

* THE DRILL FLASH FLOOD IS EXPECTED TO BE NEAR...
  HONEY BROOK AT 955 AM EST...
  RADNOR TOWNSHIP AT 955 AM EST...
  WILLOW GROVE AT 1000 AM EST...
  PERKASIE AT 1050 AM EST...
  THE CITY OF PHILADELPHIA AT 1005 AM EST...

IF THIS WERE AN ACTUAL WARNING...WE WOULD PROVIDE DETAILS OF DAMAGE
AND SUGGEST SAFE LOCATIONS AS SHELTER.

AGAIN...THIS IS A DRILL TORNADO WARNING. NO DAMAGING WEATHER IS
OCCURRING AT THIS TIME.

NNNN

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 23, 9:40 AM ESTFlash Flood WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton65 min

Nearby

Flash Flood Warnings in Pennsylvania, 2000Every flash flood warning in 2000

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.