Alert archive / New Jersey / Flash Flood Warnings in 2020

Flash Flood Warning 53, NWS Philadelphia/Mount Holly

August 12, 2020Burlington County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 12, 2020, 1:12 PM EDT for Burlington County, New Jersey. It was in force for 3 hr. 6 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
Aug 12, 2020, 1:12 PM EDT (17:12 UTC)
Expired
Aug 12, 2020, 3:59 PM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Burlington County, NJ

The radar

The Philadelphia radar (KDIX), 37 km from the middle of the area, began a volume at 17:14 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
Aug 12, 1:30 PM EDTFLASH FLOODMaple Shade, NJSEVERAL WATER RESCUES CONDUCTED IN THE MAPLE SHADE AREA. TIME BASED ON DISPATCH REPORTS.
Aug 12, 1:52 PM EDTFLOOD1 Ene Maple Shade, NJFLOODING ON NJ 73 SOUTHBOUND AT CR 537/MAIN ST (MAPLE SHADE TWP) LEFT LANE CLOSED.
Aug 12, 2:02 PM EDTFLASH FLOOD1 N Fellowship, NJCORRECTS PREVIOUS FLOOD REPORT FROM 1 N FELLOWSHIP. FLOODING ON NJ 38 BOTH DIRECTIONS CR 608/LENOLA RD (MAPLE SHADE TWP) ALL LANES CLOSED. SEVERAL WATER RESCUES WERE ALSO REPORTED.
Aug 12, 2:23 PM EDTFLOOD1 N Fellowship, NJFLOODING ON NJ 38 BOTH DIRECTIONS CR 608/LENOLA RD (MAPLE SHADE TWP) ALL LANES CLOSED .
Aug 12, 2:23 PM EDTFLOOD1 N Fellowship, NJFLOODING ON NJ 38 BOTH DIRECTIONS CR 608/LENOLA RD (MAPLE SHADE TWP) ALL LANES CLOSED.
Aug 12, 3:14 PM EDTFLOODHainesport, NJFLOODING ON NJ 38 WESTBOUND AT CR 641/LUMBERTON-HAINSPORT RD (HAINESPORT TWP). JUGHANDLE CLOSED.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 5.2 hours before the alert went out and 194 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, Brookhaven, NY at 12:00Z on 2020-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1221 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, Brookhaven, NY at 12:00Z on 2020-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 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
1221 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
921 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.4

Open this sounding in Storm Lab

The text

As transmitted.

168 
WGUS51 KPHI 121712
FFWPHI
NJC005-122115-
/O.NEW.KPHI.FF.W.0053.200812T1712Z-200812T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
112 PM EDT Wed Aug 12 2020

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Northern Burlington County in southern New Jersey...

* Until 515 PM EDT.

* At 111 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have 
  already fallen...and more rain is moving in. Flash flooding is 
  ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Some locations that could experience flooding include...
  Evesham, Mount Laurel, Willingboro, Medford, Lumberton, 
  Burlington, Mount Holly, Riverside, Palmyra, Presidential Lakes 
  Estates, Beverly, Pemberton, Wrightstown, Ramblewood, Marlton, 
  Leisuretowne, Jacksonville, Georgetown and Crosswicks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3986 7489 3993 7498 3994 7498 3995 7501
      3998 7502 3998 7501 4002 7503 4005 7498
      4016 7464 4012 7457 3992 7447 3991 7447

FLASH FLOOD...RADAR INDICATED

$$

JJM
1 follow-up statement
776 
WGUS71 KPHI 121959
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
359 PM EDT Wed Aug 12 2020

NJC005-122006-
/O.CAN.KPHI.FF.W.0053.000000T0000Z-200812T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-
359 PM EDT Wed Aug 12 2020

...THE FLASH FLOOD WARNING FOR NORTHERN BURLINGTON COUNTY IS
CANCELLED...

Flooding is no longer expected to pose a threat in the northeastern 
portion of the county. While flooding may still be occurring in the 
northwestern portion of the county, a different flash flood warning 
is in effect for that area.

Please continue to heed any remaining road closures.

LAT...LON 3986 7489 3993 7498 3994 7498 3995 7501
      3998 7502 3998 7501 4002 7503 4005 7498
      4016 7464 4012 7457 3992 7447 3991 7447

$$

JJM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 12:06 PM EDTSpecial Weather StatementPHIMonmouth24 min
Aug 12, 12:16 PM EDTSpecial Weather StatementPHIBurlington29 min
Aug 12, 12:33 PM EDTSevere Thunderstorm WarningPHIBurlington42 min
Aug 12, 12:43 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester, Mercer, Monmouth, Ocean and 1 more3 hr
Aug 12, 12:45 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean45 min
Aug 12, 1:12 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester, Monmouth, Ocean48 min
Aug 12, 1:25 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean50 min
Aug 12, 1:54 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester51 min
Aug 12, 1:57 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Ocean48 min
Aug 12, 2:40 PM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester3 hr
Aug 12, 2:42 PM EDTSevere Thunderstorm WarningPHIBurlington, Ocean25 min
Aug 12, 2:44 PM EDTSevere Thunderstorm WarningPHICamden, Gloucester46 min
Aug 12, 3:12 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester, Salem29 min
Aug 12, 3:54 PM EDTSpecial Marine WarningPHI53 min

Nearby

Flash Flood Warnings in New Jersey, 2020Every flash flood warning in 2020

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.