Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 46, NWS Philadelphia/Mount Holly

June 15, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Jun 15, 2021, 12:04 AM EDT. It was in force for 116 min. 2 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: Jun 15, 2021, 12:04 AM EDT (04:04 UTC)
Expired: Jun 15, 2021, 2:00 AM EDT
In force: 116 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 49.0 mph

The radar

The Dover AFB radar (KDOX), 22 km from the middle of the area, began a volume at 04:07 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

Time	Report	Where	Remark
Jun 15, 1:05 AM EDT	MARINE TSTM WIND 42	1 Ssw North Cape May, NJ	42 MPH GUST AT THE CAPE MAY WEATHERFLOW SITE IN LOWER TOWNSHIP.
Jun 15, 1:15 AM EDT	MARINE TSTM WIND 42	North Wildwood, NJ	42 MPH GUST AT NORTH WILDWOOD SENSOR.

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

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 4.1 hours before the alert went out and 99 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: 464 J/kg
Mixed-layer CIN: -64 J/kg
Mixed-layer LCL: 989 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 38 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

097 
WHUS51 KPHI 150404
SMWPHI
ANZ430-431-453>455-150600-
/O.NEW.KPHI.MA.W.0046.210615T0404Z-210615T0600Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
1204 AM EDT Tue Jun 15 2021

The National Weather Service in Mount Holly NJ has issued a

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

* Until 200 AM EDT.

* At 1203 AM EDT, strong thunderstorms were located along a line
  extending from 9 nm northwest of Bowers Beach to 17 nm west of
  Slaughter Beach to 20 nm east of Miles River, moving east at 25
  knots.

  HAZARD...Wind gusts to nearly 50 knots and small hail.

  SOURCE...Radar.

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

* Locations impacted include...
  Brown Shoal Light, Fenwick Island, Buoy 3fb, Fourteen Foot Bank
  Light, Slaughter Beach, Cape Henlopen, East Point, Bowers Beach,
  Rehoboth Beach, Cape May Point, Miah Maull Light, Brandywine Shoal
  Light, Indian River Inlet Bridge, Wildwood, Overfalls Shoal, Cape
  May Reef, Bethany Beach, Buoy 2ms, Cross Ledge Light and Wildwood
  Reef.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are
expected.

&&

LAT...LON 3920 7496 3909 7455 3874 7474 3845 7501
      3845 7507 3847 7511 3852 7513 3851 7520
      3858 7534 3864 7531 3864 7524 3872 7524
      3875 7520 3876 7530 3883 7529 3894 7541
      3899 7539 3903 7546 3918 7547 3922 7558
TIME...MOT...LOC 0403Z 288DEG 23KT 3913 7559 3899 7568 3890 7579 

HAIL...<.75IN
WIND...49KTS

$$

Staarmann

3 follow-up statements

459 
FZUS71 KPHI 150455
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
1255 AM EDT Tue Jun 15 2021

ANZ430-431-453>455-150600-
/O.CON.KPHI.MA.W.0046.000000T0000Z-210615T0600Z/
1255 AM EDT Tue Jun 15 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 200 AM EDT...

For the following areas...
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm...
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...
Delaware Bay waters north of East Point NJ to Slaughter Beach DE...
Delaware Bay waters south of East Point NJ to Slaughter Beach DE...

At 1255 AM EDT, strong thunderstorms were located along a line
extending from near East Point to near Brown Shoal Light to 12 nm
west of Rehoboth Beach, moving east at 30 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...
Brown Shoal Light, Fenwick Island, Buoy 3fb, Fourteen Foot Bank
Light, Slaughter Beach, Cape Henlopen, East Point, Rehoboth Beach,
Cape May Point, Brandywine Shoal Light, Indian River Inlet Bridge,
Wildwood, Overfalls Shoal, Cape May Reef, Bethany Beach, Buoy 2ms,
Wildwood Reef and Sea Isle City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are
expected.

&&

LAT...LON 3921 7508 3920 7496 3916 7483 3909 7455
      3874 7474 3845 7501 3845 7507 3847 7511
      3851 7511 3852 7513 3851 7520 3858 7534
      3864 7531 3864 7524 3872 7524 3875 7520
      3876 7529 3883 7529 3894 7541
TIME...MOT...LOC 0455Z 286DEG 28KT 3914 7495 3886 7515 3867 7534 

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

$$

Staarmann

781 
FZUS71 KPHI 150525
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
125 AM EDT Tue Jun 15 2021

ANZ430-150534-
/O.CAN.KPHI.MA.W.0046.000000T0000Z-210615T0600Z/
125 AM EDT Tue Jun 15 2021

...THE SPECIAL MARINE WARNING IS CANCELLED...

The affected areas were...
Upper Delaware Bay...

The thunderstorms have moved out of the warned area and no longer 
pose a significant threat to boaters.

A Severe Thunderstorm Watch remains in effect until 200 AM EDT for
southern Delaware...southern New Jersey...and the adjacent coastal
waters.

LAT...LON 3864 7531 3864 7524 3872 7524 3876 7521
      3876 7529 3916 7483 3909 7455 3874 7474
      3845 7501 3845 7507 3847 7511 3851 7511
      3852 7513 3851 7520 3858 7534
TIME...MOT...LOC 0524Z 274DEG 28KT 3908 7467 3890 7477 3874 7498 

$$

ANZ431-453>455-150600-
/O.CON.KPHI.MA.W.0046.000000T0000Z-210615T0600Z/
125 AM EDT Tue Jun 15 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 200 AM EDT...

For the following areas...
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm...
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...
Delaware Bay waters south of East Point NJ to Slaughter Beach DE...

At 124 AM EDT, strong thunderstorms were located along a line
extending from near The Lump to near Buoy 3fb to near Rehoboth 
Beach, moving east at 30 knots. A few measured gusts of 35 to 40 
knots have been observed with this line of storms.

HAZARD...Wind gusts to 40 knots.

SOURCE...Coast Guard.

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

Locations impacted include...
Brown Shoal Light, Fenwick Island, Buoy 3fb, Cape Henlopen, Rehoboth
Beach, Cape May Point, Indian River Inlet Bridge, Wildwood, Overfalls
Shoal, Cape May Reef, Bethany Beach, Buoy 2ms, Wildwood Reef and Sea
Isle City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are
expected.

&&

LAT...LON 3864 7531 3864 7524 3872 7524 3876 7521
      3876 7529 3916 7483 3909 7455 3874 7474
      3845 7501 3845 7507 3847 7511 3851 7511
      3852 7513 3851 7520 3858 7534
TIME...MOT...LOC 0524Z 274DEG 28KT 3908 7467 3890 7477 3874 7498 

HAIL...0.00IN
WIND...40KTS

$$

Staarmann

996 
FZUS71 KPHI 150536
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
136 AM EDT Tue Jun 15 2021

ANZ431-150546-
/O.CAN.KPHI.MA.W.0046.000000T0000Z-210615T0600Z/
136 AM EDT Tue Jun 15 2021

...THE SPECIAL MARINE WARNING IS CANCELLED...

The affected areas were...
Lower Delaware Bay...

The thunderstorms have moved out of the warned area and no longer 
pose a significant threat to boaters.

A Severe Thunderstorm Watch remains in effect until 200 AM EDT for
southern Delaware...and southern New Jersey.

LAT...LON 3845 7508 3846 7509 3849 7511 3880 7496
      3895 7491 3913 7470 3909 7456 3907 7456
      3874 7474 3846 7500
TIME...MOT...LOC 0536Z 287DEG 23KT 3906 7459 3888 7469 3855 7499 

$$

ANZ453>455-150600-
/O.CON.KPHI.MA.W.0046.000000T0000Z-210615T0600Z/
136 AM EDT Tue Jun 15 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 200 AM EDT...

For the following areas...
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm...
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...

At 136 AM EDT, strong thunderstorms were located along a line
extending from near The Lump to Cape May Reef to near Bethany Beach, 
moving east at 25 knots. A few measured gusts of 35 to 40 knots have 
been observed with this line of storms.

HAZARD...Wind gusts to 40 knots.

SOURCE...Coast Guard.

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

Locations impacted include...
Fenwick Island, Buoy 3fb, Cape May Reef, Bethany Beach, Buoy 2ms,
Wildwood Reef and Wildwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are
expected.

&&

LAT...LON 3845 7508 3846 7509 3849 7511 3880 7496
      3895 7491 3913 7470 3909 7456 3907 7456
      3874 7474 3846 7500
TIME...MOT...LOC 0536Z 287DEG 23KT 3906 7459 3888 7469 3855 7499 

HAIL...0.00IN
WIND...40KTS

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 14, 8:08 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	52 min
Jun 14, 8:34 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester	41 min
Jun 14, 8:55 PM EDT	Severe Thunderstorm Warning	PHI	Gloucester	50 min
Jun 14, 9:11 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Mercer, Middlesex, Monmouth and 1 more	49 min
Jun 14, 9:12 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Mercer, Middlesex, Monmouth and 1 more	74 min
Jun 14, 9:17 PM EDT	Flash Flood Warning	PHI	Burlington, Camden	3 hr
Jun 14, 9:29 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester	46 min
Jun 14, 9:54 PM EDT	Areal Flood Advisory	PHI	Monmouth	97 min
Jun 14, 9:58 PM EDT	Severe Thunderstorm Warning	PHI	Monmouth	32 min
Jun 14, 10:01 PM EDT	Special Marine Warning	PHI		89 min
Jun 14, 10:07 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Gloucester, Ocean	53 min
Jun 14, 10:51 PM EDT	Special Marine Warning	PHI		114 min
Jun 14, 11:07 PM EDT	Special Marine Warning	PHI		113 min
Jun 14, 11:21 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Ocean	39 min
Jun 14, 11:42 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Cumberland, Gloucester, Salem	63 min
Jun 14, 11:47 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Cumberland, Ocean, Salem	118 min
Jun 15, 12:12 AM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Gloucester	51 min
Jun 15, 1:00 AM EDT	Special Marine Warning	PHI		88 min
Jun 14, 11:12 PM EDT	Severe Thunderstorm Warning	PHI	Kent	63 min
Jun 14, 11:39 PM EDT	Areal Flood Advisory	PHI	Kent, New Castle	85 min
Jun 14, 11:51 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	54 min
Jun 14, 11:54 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.