Alert archive / New Jersey / Areal Flood Advisories in 2021

Areal Flood Advisory 3, NWS Philadelphia/Mount Holly

February 28, 20218 counties in New Jersey; Bucks County, Delaware County, Philadelphia County, Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood advisory at Feb 28, 2021, 5:20 PM EST for 8 counties in New Jersey; Bucks County, Delaware County, Philadelphia County, Pennsylvania; New Castle County, Delaware. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Feb 28, 2021, 5:20 PM EST (22:20 UTC)
Expired
Feb 28, 2021, 8:15 PM EST
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Ocean County, NJ, Salem County, NJ, Bucks County, PA, Delaware County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 56 km from the middle of the area, began a volume at 22:24 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

Wallops Is Stn, VA (KWAL), launched 12:00Z, 10.3 hours before the alert went out and 201 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, Wallops Is Stn, VA at 12:00Z on 2021-02-28Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 12:00Z on 2021-02-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 6 square meters per square second.1939587897Sfc1 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
1716 m above ground
0-6 km bulk shear
85 kt
0-1 km storm-relative helicity
6 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

235 
WGUS81 KPHI 282220 RRA
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
520 PM EST Sun Feb 28 2021

DEC003-NJC001-005-007-009-011-015-029-033-PAC017-045-101-010115-
/O.NEW.KPHI.FA.Y.0003.210228T2220Z-210301T0115Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Atlantic NJ-Burlington NJ-Camden NJ-Cape May NJ-
Cumberland NJ-Gloucester NJ-Ocean NJ-Salem NJ-Bucks PA-Delaware PA-
Philadelphia PA-
520 PM EST Sun Feb 28 2021

The National Weather Service in Mount Holly has issued a

* Flood Advisory for...
  Eastern New Castle County in northern Delaware...
  Atlantic County in southern New Jersey...
  Burlington County in southern New Jersey...
  Camden County in southern New Jersey...
  Cape May County in southern New Jersey...
  Cumberland County in southern New Jersey...
  Gloucester County in southern New Jersey...
  Ocean County in southern New Jersey...
  Salem County in southern New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...
  Southeastern Delaware County in southeastern Pennsylvania...
  Southeastern Philadelphia County in southeastern Pennsylvania...

* Until 815 PM EST.

* At 520 PM EST, Doppler radar indicated heavy rain. Minor flooding 
  is ongoing or expected to begin shortly in the advisory area. 
  Between 0.5 and 1 inch of rain has fallen.

Some locations that may experience flooding include...
  Philadelphia, Camden, Wilmington, Vineland, Atlantic City, 
  Millville, Bridgeton, Ocean City, Gloucester City, Cape May, 
  Cumberland, and Cherry Hill.

This includes the following highways...
	New Jersey Turnpike between exits 1 and 7A.
	Interstate 95 in Pennsylvania between mile markers 14 and 20.
	Interstate 76 in Pennsylvania between mile markers 349 and 351.
	Interstate 76 in New Jersey between mile markers 0 and 3.
	Interstate 295 in New Jersey between mile markers 0 and 57.
	Interstate 676 in New Jersey between mile markers 0 and 3.
	Garden State Parkway between mile markers 0 and 27...and
	between mile markers 29 and 30...and
	between mile markers 32 and 80.
	Atlantic City Expressway between mile markers 0 and 44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Advisory means river or stream flows are elevated, or 
ponding of water in urban or other areas is occurring or is imminent.

&&

LAT...LON 3960 7559 3972 7553 4015 7472 4018 7470
      4008 7455 4009 7453 3979 7391 3890 7495
      3928 7528 3945 7553

$$

NC
1 follow-up statement
271 
WGUS81 KPHI 010117
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
817 PM EST Sun Feb 28 2021

DEC003-NJC001-005-007-009-011-015-029-033-PAC017-045-101-010127-
/O.EXP.KPHI.FA.Y.0003.000000T0000Z-210301T0115Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Atlantic NJ-Burlington NJ-Camden NJ-Cape May NJ-
Cumberland NJ-Gloucester NJ-Ocean NJ-Salem NJ-Bucks PA-Delaware PA-
Philadelphia PA-
817 PM EST Sun Feb 28 2021

...FLOOD ADVISORY HAS EXPIRED FOR EASTERN NEW CASTLE, ATLANTIC, 
BURLINGTON, CAMDEN, CAPE MAY, CUMBERLAND, GLOUCESTER, OCEAN, SALEM, 
SOUTHEASTERN BUCKS, SOUTHEASTERN DELAWARE, AND SOUTHEASTERN 
PHILADELPHIA COUNTIES...

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

LAT...LON 3960 7559 3972 7553 4015 7472 4018 7470
      4008 7455 4009 7453 3979 7391 3890 7495
      3928 7528 3945 7553

$$

Davis

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 28, 2:45 AM ESTGale WatchPHI13 hr
Feb 28, 3:14 PM ESTWind AdvisoryPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more42 hr
Feb 28, 3:16 PM ESTGale WarningPHI45 hr
Feb 28, 5:20 PM ESTAreal Flood AdvisoryPHIKent, New Castle3 hr

Nearby

Areal Flood Advisories in New Jersey, 2021Areal Flood Advisories in Pennsylvania, 2021Areal Flood Advisories in Delaware, 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.