Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 78, NWS Philadelphia/Mount Holly

July 9, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Jul 9, 2021, 1:49 AM EDT. It was in force for 26 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 9, 2021, 1:49 AM EDT (05:49 UTC)
Expired: Jul 9, 2021, 2:15 AM EDT
In force: 26 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.0 in
Wind: 34.0 mph

The radar

The Dover AFB radar (KDOX), 37 km from the middle of the area, began a volume at 05:48 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 00:00Z, 5.8 hours before the alert went out and 119 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: 440 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 675 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 151 m²/s²
0-3 km storm-relative helicity: 336 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.3

Open this sounding in Storm Lab

The text

As transmitted.

545 
WHUS51 KPHI 090549
SMWPHI
ANZ431-453-454-090615-
/O.NEW.KPHI.MA.W.0078.210709T0549Z-210709T0615Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
149 AM EDT Fri Jul 9 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  Lower Delaware Bay...
  Coastal waters from Great Egg Inlet NJ to Cape Henlopen DE out 20
  nm...

* Until 215 AM EDT.

* At 149 AM EDT, a severe thunderstorm capable of producing
  waterspouts was located over Cape May Point, moving northwest at 25
  knots.

  HAZARD...Waterspouts and wind gusts 34 knots or greater.

  SOURCE...Radar.

  IMPACT...Waterspouts can easily overturn boats and create locally 
           hazardous seas. Small craft could be damaged in briefly 
           higher winds and suddenly higher waves.

* Locations impacted include...
  Brandywine Shoal Light, Brown Shoal Light and Cape May Point. 

LAT...LON 3903 7514 3895 7485 3890 7487 3888 7493
      3893 7519 3900 7521
TIME...MOT...LOC 0549Z 114DEG 27KT 3894 7497 

WATERSPOUT...POSSIBLE
HAIL...0.00IN
WIND...>34KTS

$$

BAH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 8, 10:25 PM EDT	Areal Flood Advisory	PHI	Cape May, Cumberland	7 hr
Jul 8, 11:02 PM EDT	Special Marine Warning	PHI		88 min
Jul 8, 11:59 PM EDT	Areal Flood Advisory	PHI	Salem	5 hr
Jul 9, 12:07 AM EDT	Special Marine Warning	PHI		53 min
Jul 9, 12:08 AM EDT	Areal Flood Advisory	PHI	Atlantic, Camden, Gloucester	6 hr
Jul 9, 12:25 AM EDT	Special Marine Warning	PHI		95 min
Jul 9, 1:34 AM EDT	Special Marine Warning	PHI		86 min
Jul 9, 2:05 AM EDT	Areal Flood Advisory	PHI	Burlington, Monmouth, Ocean	8 hr
Jul 9, 2:50 AM EDT	Tornado Warning	PHI	Atlantic, Cape May, Cumberland	25 min
Jul 9, 2:53 AM EDT	Special Marine Warning	PHI		68 min
Jul 9, 3:38 AM EDT	Tornado Warning	PHI	Atlantic, Burlington, Ocean	18 min
Jul 9, 3:51 AM EDT	Special Marine Warning	PHI		84 min
Jul 9, 4:08 AM EDT	Gale Warning	PHI		3 hr
Jul 9, 4:41 AM EDT	Tornado Warning	PHI	Monmouth, Ocean	34 min
Jul 9, 4:44 AM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex	5 hr
Jul 9, 4:54 AM EDT	Areal Flood Advisory	PHI	Morris, Somerset	5 hr
Jul 9, 4:58 AM EDT	Special Marine Warning	PHI		39 min
Jul 9, 5:34 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	2 hr
Jul 9, 6:19 PM EDT	Severe Thunderstorm Warning	PHI	Salem	41 min
Jul 9, 6:24 PM EDT	Special Marine Warning	PHI		66 min
Jul 9, 6:50 PM EDT	Areal Flood Advisory	PHI	Gloucester, Salem	2 hr
Jul 9, 6:57 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	63 min
Jul 9, 7:17 PM EDT	Severe Thunderstorm Warning	PHI	Camden, Gloucester	23 min
Jul 9, 7:39 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Morris, Sussex, Warren	2 hr
Jul 9, 7:43 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Camden, Cape May, Cumberland, Gloucester, Salem	62 min
Jul 9, 7:46 PM EDT	Areal Flood Advisory	PHI	Atlantic, Camden, Cumberland, Gloucester, Salem	108 min
Jul 9, 5:17 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	43 min
Jul 9, 6:55 PM EDT	Special Weather Statement	PHI	Carbon	35 min
Jul 9, 7:07 PM EDT	Areal Flood Advisory	PHI	Carbon, Lehigh, Monroe, Northampton	3 hr
Jul 9, 7:31 PM EDT	Special Weather Statement	PHI	Northampton	29 min
Jul 8, 10:19 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	5 hr
Jul 8, 11:37 PM EDT	Tornado Warning	PHI	Sussex	23 min
Jul 8, 11:59 PM EDT	Tornado Warning	PHI	Sussex	12 min
Jul 9, 12:04 AM EDT	Tornado Warning	PHI	Sussex	26 min
Jul 9, 12:11 AM EDT	Tornado Warning	PHI	Sussex	35 min
Jul 9, 12:28 AM EDT	Tornado Warning	PHI	Sussex	17 min
Jul 9, 4:54 PM EDT	Special Weather Statement	PHI	New Castle	66 min

Nearby

Special Marine Warnings in New Jersey, 2021 Every special marine warning 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.