Alert archive / New Jersey / Areal Flood Advisories in 2021

Areal Flood Advisory 9, NWS Philadelphia/Mount Holly

April 12, 2021Burlington County, Camden County, Gloucester County, New Jersey; Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood advisory at Apr 12, 2021, 1:12 AM EDT for Burlington County, Camden County, Gloucester County, New Jersey; Philadelphia County, Pennsylvania. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued
Apr 12, 2021, 1:12 AM EDT (05:12 UTC)
Expired
Apr 12, 2021, 2:19 AM EDT
In force
67 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 61 km from the middle of the area, began a volume at 05:15 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, 5.2 hours before the alert went out and 219 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 00:00Z on 2021-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2021-04-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 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
6 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
434 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
293 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

919 
WGUS81 KPHI 120512
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
112 AM EDT Mon Apr 12 2021

NJC005-007-015-PAC101-120645-
/O.NEW.KPHI.FA.Y.0009.210412T0512Z-210412T0645Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Camden NJ-Gloucester NJ-Philadelphia PA-
112 AM EDT Mon Apr 12 2021

The National Weather Service in Mount Holly has issued a

* Urban and Small Stream Flood Advisory for...
  West Central Burlington County in southern New Jersey...
  Northwestern Camden County in southern New Jersey...
  North Central Gloucester County in southern New Jersey...
  Central Philadelphia County in southeastern Pennsylvania...

* Until 245 AM EDT.

* At 112 AM EDT, Doppler radar and automated rain gauges indicated 
  heavy rain due to thunderstorms. This will cause urban and small 
  stream flooding. Up to 1 inch of rain has fallen.

* Some locations that will experience flooding include...
  Camden, Gloucester City, Cherry Hill, Deptford, West Deptford, 
  Bellmawr, Woodbury, Riverside, Palmyra, Paulsboro, and Magnolia.

This includes the following highways...
	New Jersey Turnpike between exits 3 and 4.
	Interstate 95 in Pennsylvania between mile markers 15 and 31.
	Interstate 76 in Pennsylvania between mile markers 350 and 351.
	Interstate 76 in New Jersey between mile markers 0 and 3.
	Interstate 295 in New Jersey between mile markers 20 and 37.
	Interstate 676 in New Jersey between mile markers 0 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3987 7522 3995 7515 4004 7507 4004 7499
      4003 7490 3993 7495 3987 7500 3980 7510
      3981 7519 3982 7522 3986 7523 3986 7522
      3987 7521

$$

Deal
1 follow-up statement
992 
WGUS81 KPHI 120619
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
219 AM EDT Mon Apr 12 2021

NJC005-007-015-PAC101-120629-
/O.CAN.KPHI.FA.Y.0009.000000T0000Z-210412T0645Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Camden NJ-Gloucester NJ-Philadelphia PA-
219 AM EDT Mon Apr 12 2021

...THE URBAN AND SMALL STREAM FLOOD ADVISORY IS CANCELLED FOR WEST 
CENTRAL BURLINGTON, NORTHWESTERN CAMDEN, NORTH CENTRAL GLOUCESTER, 
AND CENTRAL PHILADELPHIA COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3987 7522 3995 7515 4004 7507 4004 7499
      4003 7490 3993 7495 3987 7500 3980 7510
      3981 7519 3982 7522 3986 7523 3986 7522
      3987 7521

$$

Deal

Nearby

Areal Flood Advisories in New Jersey, 2021Areal Flood Advisories in Pennsylvania, 2021Every areal flood advisory in 2021

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.