Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 53, NWS Philadelphia/Mount Holly

June 22, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Jun 22, 2021, 12:51 PM EDT. It was in force for 114 min. 1 report 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 22, 2021, 12:51 PM EDT (16:51 UTC)
Expired
Jun 22, 2021, 2:45 PM EDT
In force
114 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), 46 km from the middle of the area, began a volume at 16:51 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

TimeReportWhereRemark
Jun 22, 1:32 PM EDTMARINE TSTM WIND 441 Ssw North Cape May, NJAT CAPE MAY WEATHERFLOW GAUGE... PEAK GUST 48 MPH MEASURED AT 1:57 PM.

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 12:00Z, 4.9 hours before the alert went out and 143 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 2021-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1075 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 2021-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 39 square meters per square second.193958Sfc1 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
1075 J/kg
Mixed-layer CIN
-97 J/kg
Mixed-layer LCL
1069 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.4

Open this sounding in Storm Lab

The text

As transmitted.

409 
WHUS51 KPHI 221651
SMWPHI
ANZ430-431-221845-
/O.NEW.KPHI.MA.W.0053.210622T1651Z-210622T1845Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
1251 PM EDT Tue Jun 22 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  Delaware Bay...

* Until 245 PM EDT.

* At 1250 PM EDT, a surge of stronger winds was located along a line 
  extending from 22 nm east of Pea Patch Island to 13 nm east of 
  Miles River, moving east at 15 knots. Winds should remain elevated 
  for a couple of hours following the passage of the front.

  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...
  Brown Shoal Light, Fourteen Foot Bank Light, Slaughter Beach, Cape
  Henlopen, East Point, Bowers Beach, Woodland Beach, Miah Maull
  Light, Ship John Shoal Light, Brandywine Shoal Light, Fortesque
  Beach, Sea Breeze, Cross Ledge Light, Cape May Point and Rehoboth
  Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3930 7554 3948 7545 3946 7533 3943 7534
      3944 7519 3927 7513 3926 7507 3929 7506
      3942 7508 3941 7503 3930 7491 3923 7495
      3913 7483 3872 7513 3881 7521 3879 7525
      3882 7523 3905 7546 3918 7547 3923 7561
TIME...MOT...LOC 1650Z 281DEG 16KT 3969 7511 3873 7594 

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

$$

CMS
3 follow-up statements
153 
FZUS71 KPHI 221738
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
138 PM EDT Tue Jun 22 2021

ANZ430-431-221845-
/O.CON.KPHI.MA.W.0053.000000T0000Z-210622T1845Z/
138 PM EDT Tue Jun 22 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 245 PM EDT...

For the following areas...
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 137 PM EDT, strong northwest winds were occurring on Delaware Bay 
in response to a frontal passage. Gusts to 39 knots were observed 
recently near the Cape May Ferry. These strong winds will likely 
continue for the next hour.

HAZARD...Wind gusts to 40 knots.

SOURCE...Surface observations.

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

Locations impacted include...
Brown Shoal Light, Fourteen Foot Bank Light, Slaughter Beach, Cape
Henlopen, East Point, Bowers Beach, Woodland Beach, Miah Maull Light,
Ship John Shoal Light, Brandywine Shoal Light, Fortesque Beach, Sea
Breeze, Cross Ledge Light, Cape May Point and Rehoboth Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3930 7554 3948 7545 3946 7533 3943 7534
      3944 7519 3927 7513 3926 7507 3929 7506
      3942 7508 3941 7503 3930 7491 3923 7495
      3913 7483 3872 7513 3881 7521 3879 7525
      3882 7523 3905 7546 3918 7547 3923 7561
TIME...MOT...LOC 1737Z 294DEG 28KT 3958 7476 3863 7559 

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

$$

CMS
489 
FZUS71 KPHI 221759
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
159 PM EDT Tue Jun 22 2021

ANZ430-431-221845-
/O.CON.KPHI.MA.W.0053.000000T0000Z-210622T1845Z/
159 PM EDT Tue Jun 22 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 245 PM EDT...

For the following areas...
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 158 PM EDT, strong winds continued across Delaware Bay. Gusts 
were exceeding 40 knots at Cape May and at Lewes. These strong winds 
will likely continue for the next hour.

HAZARD...Wind gusts to 40 knots.

SOURCE...Surface observations.

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

Locations impacted include...
Brown Shoal Light, Fourteen Foot Bank Light, Slaughter Beach, Cape
Henlopen, East Point, Bowers Beach, Woodland Beach, Miah Maull Light,
Ship John Shoal Light, Brandywine Shoal Light, Fortesque Beach, Sea
Breeze, Cross Ledge Light, Cape May Point and Rehoboth Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3930 7554 3948 7545 3946 7533 3943 7534
      3944 7519 3927 7513 3926 7507 3929 7506
      3942 7508 3941 7503 3930 7491 3923 7495
      3913 7483 3872 7513 3881 7521 3879 7525
      3882 7523 3905 7546 3918 7547 3923 7561
TIME...MOT...LOC 1758Z 281DEG 16KT 3956 7465 3861 7549 

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

$$

CMS
723 
FZUS71 KPHI 221842
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
242 PM EDT Tue Jun 22 2021

ANZ430-431-221850-
/O.EXP.KPHI.MA.W.0053.000000T0000Z-210622T1845Z/
242 PM EDT Tue Jun 22 2021

...THE SPECIAL MARINE WARNING WILL EXPIRE AT 245 PM EDT...

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

The stronger winds have diminished and are now confined to far lower 
portions of Delaware Bay, where a special marine warning remains in 
effect. Mariners should continue to exercise caution on Delaware 
Bay, as frequent gusts up to 30 knots are still possible.

LAT...LON 3930 7554 3948 7545 3946 7533 3943 7534
      3944 7519 3927 7513 3926 7507 3929 7506
      3942 7508 3941 7503 3930 7491 3923 7495
      3913 7483 3872 7513 3881 7521 3879 7525
      3882 7523 3905 7546 3918 7547 3923 7561
TIME...MOT...LOC 1840Z 281DEG 16KT 3952 7442 3858 7526 

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 8:13 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren62 min
Jun 21, 8:31 PM EDTSpecial Marine WarningPHI59 min
Jun 21, 10:01 PM EDTSpecial Marine WarningPHI29 min
Jun 22, 11:46 AM EDTSpecial Marine WarningPHI44 min
Jun 22, 1:25 PM EDTSpecial Marine WarningPHI65 min
Jun 22, 1:47 PM EDTSpecial Marine WarningPHI118 min
Jun 22, 2:27 PM EDTSpecial Marine WarningPHI93 min
Jun 22, 3:05 PM EDTSmall Craft AdvisoryPHI15 hr
Jun 22, 3:26 PM EDTSpecial Marine WarningPHI68 min
Jun 21, 9:28 PM EDTSpecial Weather StatementPHIKent47 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.