Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 19, NWS Philadelphia/Mount Holly

May 8, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at May 8, 2021, 4:28 PM EDT. It was in force for 62 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: May 8, 2021, 4:28 PM EDT (20:28 UTC)
Expired: May 8, 2021, 5:30 PM EDT
In force: 62 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 40.0 mph

The radar

The Dover AFB radar (KDOX), 70 km from the middle of the area, began a volume at 20:32 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, 8.5 hours before the alert went out and 117 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1134 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 47 m²/s²
0-3 km storm-relative helicity: 47 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

031 
WHUS51 KPHI 082028
SMWPHI
ANZ431-453>455-473-475-082130-
/O.NEW.KPHI.MA.W.0019.210508T2028Z-210508T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
428 PM EDT Sat May 8 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  Lower Delaware Bay...
  Coastal and outer waters from Great Egg Inlet NJ to Fenwick Island
  DE...

* Until 530 PM EDT.

* At 428 PM EDT, strong thunderstorms were located along a line
  extending from near Brown Shoal Light to near Cape Henlopen, moving
  east at 35 knots.

  HAZARD...Wind gusts to 40 knots and small hail.

  SOURCE...Radar.

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

* Locations impacted include...
  Overfalls Shoal, Five Fathoms Buoy, Brown Shoal Light, Buoy 4fb,
  Cape May Reef, Cape Henlopen, Rehoboth Beach, Cape May Point and
  Buoy 2ms.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

&&

LAT...LON 3886 7415 3850 7456 3878 7527 3899 7506
TIME...MOT...LOC 2028Z 286DEG 34KT 3892 7504 3878 7517 

HAIL...<.75IN
WIND...40KTS

$$

SFJ

1 follow-up statement

158 
FZUS71 KPHI 082104
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
504 PM EDT Sat May 8 2021

ANZ431-082114-
/O.CAN.KPHI.MA.W.0019.000000T0000Z-210508T2130Z/
504 PM EDT Sat May 8 2021

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

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

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

LAT...LON 3870 7506 3897 7496 3886 7415 3850 7456
TIME...MOT...LOC 2104Z 286DEG 34KT 3883 7464 3869 7477 

$$

ANZ453>455-473-475-082130-
/O.CON.KPHI.MA.W.0019.000000T0000Z-210508T2130Z/
504 PM EDT Sat May 8 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 530 PM 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...
Waters from Cape May NJ to Fenwick Island DE out 20 to 40 nm...
Waters from Great Egg Inlet NJ to Cape May NJ out 20 to 40 nm...

At 504 PM EDT, showers capable of producing waterspouts were located
along a line extending from Buoy 4fb to 9 nm south of Buoy 2ms,
moving east at 35 knots.

HAZARD...Waterspouts, wind gusts to 40 knots, and small hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Five Fathoms Buoy, Cape May Point, Buoy 2ms, Buoy 4fb and Cape May
Reef.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

Move to safe harbor until hazardous weather passes.

&&

LAT...LON 3870 7506 3897 7496 3886 7415 3850 7456
TIME...MOT...LOC 2104Z 286DEG 34KT 3883 7464 3869 7477 

WATERSPOUT...POSSIBLE
HAIL...<.75IN
WIND...40KTS

$$

SFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
May 8, 11:22 AM EDT	Special Weather Statement	PHI	Monmouth	38 min
May 8, 1:12 PM EDT	Special Weather Statement	PHI	Monmouth	33 min
May 8, 1:15 PM EDT	Areal Flood Advisory	PHI	Middlesex, Monmouth	58 min
May 8, 1:45 PM EDT	Special Weather Statement	PHI	Ocean	15 min
May 8, 2:01 PM EDT	Special Weather Statement	PHI	Ocean	14 min
May 8, 2:34 PM EDT	Small Craft Advisory	PHI		7 hr
May 8, 2:42 PM EDT	Special Weather Statement	PHI	Middlesex, Monmouth, Morris	48 min
May 8, 2:47 PM EDT	Special Marine Warning	PHI		31 min
May 8, 3:04 PM EDT	Special Weather Statement	PHI	Salem	26 min
May 8, 3:23 PM EDT	Special Weather Statement	PHI	Salem	37 min
May 8, 3:43 PM EDT	Special Marine Warning	PHI		62 min
May 8, 3:46 PM EDT	Special Weather Statement	PHI	Somerset	29 min
May 8, 3:53 PM EDT	Special Marine Warning	PHI		56 min
May 8, 4:01 PM EDT	Special Marine Warning	PHI		48 min
May 8, 4:16 PM EDT	Special Weather Statement	PHI	Cumberland	29 min
May 8, 4:21 PM EDT	Special Weather Statement	PHI	Hunterdon, Middlesex, Somerset	24 min
May 8, 4:46 PM EDT	Special Weather Statement	PHI	Hunterdon, Mercer, Middlesex, Somerset	29 min
May 8, 5:22 PM EDT	Special Marine Warning	PHI		53 min
May 8, 3:39 PM EDT	Special Weather Statement	PHI	Kent	36 min
May 8, 3:54 PM EDT	Special Weather Statement	PHI	Sussex	36 min
May 8, 4:15 PM EDT	Special Weather Statement	PHI	Sussex	30 min
May 8, 4:33 PM EDT	Special Weather Statement	PHI	Sussex	27 min
May 8, 5:56 PM EDT	Special Weather Statement	PHI	Kent	34 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.