Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 128, NWS Philadelphia/Mount Holly

August 30, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Aug 30, 2021, 6:16 PM EDT. It was in force for 89 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
Aug 30, 2021, 6:16 PM EDT (22:16 UTC)
Expired
Aug 30, 2021, 7:45 PM EDT
In force
89 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.0 in
Wind
34.0 mph

The radar

The Philadelphia radar (KDIX), 83 km from the middle of the area, began a volume at 22:18 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 161 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 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 392 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, Wallops Is Stn, VA at 12:00Z on 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -19 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
392 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
791 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-19 m²/s²
0-3 km storm-relative helicity
-9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

382 
WHUS51 KPHI 302216
SMWPHI
ANZ452>454-302345-
/O.NEW.KPHI.MA.W.0128.210830T2216Z-210830T2345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
616 PM EDT Mon Aug 30 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  
Coastal waters from Little Egg Inlet NJ to Cape Henlopen DE out 20
nm...

* Until 745 PM EDT.

* At 616 PM EDT, strong thunderstorms were located along a line
  extending from near Brigantine to near Fourteen Foot Bank Light,
  moving southeast at 5 knots.

  HAZARD...Wind gusts 34 knots or greater.

  SOURCE...Radar.

  IMPACT...Small craft could be damaged in briefly higher winds and 
           suddenly higher waves.

* Locations impacted include...
  Atlantic City, Buoy 2fb, Atlantic City Reef, Buoy 4fb, Buoy 3fb,
  Great Egg Inlet, Cape May Point, Great Egg Reef, Ocean City Reef,
  Wildwood, The Lump, 28-
  Mile Wreck, Buoy Ge, Cape May Reef, Brigantine, Sea Isle City and
  Wildwood Reef.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

Frequent lightning is occurring with these storms. If caught on the
open water, stay below deck if possible and keep away from ungrounded
metal objects.

&&

LAT...LON 3948 7450 3937 7395 3878 7463 3892 7499
TIME...MOT...LOC 2216Z 296DEG 7KT 3941 7429 3909 7518 

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

$$

Gorse
1 follow-up statement
949 
FZUS71 KPHI 302242
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
642 PM EDT Mon Aug 30 2021

ANZ452>454-302345-
/O.CON.KPHI.MA.W.0128.000000T0000Z-210830T2345Z/
642 PM EDT Mon Aug 30 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 745 PM EDT...

For the following areas...
Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm...
Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm...
Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20
nm...

At 642 PM EDT, strong thunderstorms were located along a line
extending from near Great Egg Inlet to near Sea Isle City to
Brandywine Shoal Light, moving south at 15 knots.

HAZARD...Wind gusts 34 knots or greater.

SOURCE...Radar indicated.

IMPACT...Small craft could be damaged in briefly higher winds and 
         suddenly higher waves.

Locations impacted include...
Buoy 2fb, Atlantic City Reef, Buoy 4fb, Buoy 3fb, Great Egg Inlet,
Cape May Point, Great Egg Reef, Ocean City Reef, Wildwood, The Lump,
28-
Mile Wreck, Buoy Ge, Cape May Reef, Sea Isle City, Wildwood Reef and
Atlantic City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

Frequent lightning is occurring with these storms. If caught on the
open water, stay below deck if possible and keep away from ungrounded
metal objects.

&&

LAT...LON 3937 7460 3937 7395 3878 7463 3892 7499
TIME...MOT...LOC 2242Z 353DEG 16KT 3932 7449 3912 7475 3901 7512 

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

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 5:00 AM EDTFlash Flood WatchPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more71 hr
Aug 30, 5:44 AM EDTDense Fog AdvisoryPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 3 more3 hr
Aug 30, 4:48 PM EDTSpecial Weather StatementPHIAtlantic, Cumberland27 min
Aug 30, 5:16 PM EDTSevere Thunderstorm WarningPHIAtlantic, Cape May, Cumberland44 min
Aug 30, 5:21 PM EDTSpecial Weather StatementPHIAtlantic24 min
Aug 30, 5:26 PM EDTSpecial Marine WarningPHI64 min
Aug 30, 5:44 PM EDTSpecial Marine WarningPHI61 min
Aug 30, 5:53 PM EDTSpecial Weather StatementPHIAtlantic22 min
Aug 30, 5:56 PM EDTSpecial Weather StatementPHICape May49 min
Aug 30, 6:41 PM EDTSpecial Weather StatementPHICape May34 min
Aug 30, 7:20 PM EDTSpecial Weather StatementPHICape May25 min
Aug 30, 7:31 PM EDTSpecial Marine WarningPHI59 min
Aug 30, 3:44 PM EDTSpecial Weather StatementPHINew Castle31 min
Aug 30, 4:14 PM EDTSpecial Weather StatementPHIKent31 min
Aug 30, 6:02 PM EDTSevere Thunderstorm WarningPHIKent, Sussex28 min

Nearby

Special Marine Warnings in New Jersey, 2021Every 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.