Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 6, NWS Philadelphia/Mount Holly

March 28, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Mar 28, 2021, 6:21 PM EDT. It was in force for 54 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: Mar 28, 2021, 6:21 PM EDT (22:21 UTC)
Expired: Mar 28, 2021, 7:15 PM EDT
In force: 54 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.0 in
Wind: 49.0 mph

The radar

The Dover AFB radar (KDOX), 80 km from the middle of the area, began a volume at 22:21 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, 10.4 hours before the alert went out and 180 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: 644 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 140 m²/s²
0-3 km storm-relative helicity: 249 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

301 
WHUS51 KPHI 282221
SMWPHI
ANZ430-282315-
/O.NEW.KPHI.MA.W.0006.210328T2221Z-210328T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
621 PM EDT Sun Mar 28 2021

The National Weather Service in Mount Holly NJ has issued a

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

* Until 715 PM EDT.

* At 620 PM EDT, a line of showers was located along a line 
  extending from 14 nm north of Northeast River to near Havre De 
  Grace, moving east at 40 knots.

  HAZARD...Wind gusts to nearly 50 knots.

  SOURCE...Radar.

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

* Locations impacted include...
  Pea Patch Island, Stony Point and Reedy Point. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3968 7562 3971 7558 3975 7557 3977 7551
      3974 7545 3969 7544 3961 7535 3951 7539
      3948 7533 3943 7534 3943 7529 3946 7525
      3946 7520 3938 7517 3934 7519 3936 7559
      3940 7562
TIME...MOT...LOC 2220Z 265DEG 39KT 3976 7595 3952 7606 

HAIL...0.00IN
WIND...49KTS

$$

Staarmann

1 follow-up statement

429 
FZUS71 KPHI 282236
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
636 PM EDT Sun Mar 28 2021

ANZ430-282315-
/O.CON.KPHI.MA.W.0006.000000T0000Z-210328T2315Z/
636 PM EDT Sun Mar 28 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 715 PM EDT...

For the following areas...
Delaware Bay waters north of East Point NJ to Slaughter Beach DE...

At 635 PM EDT, a line of showers was located along a line extending 
from 15 nm northwest of Reedy Point to 9 nm west of Pea Patch 
Island, moving east at 40 knots.

HAZARD...Wind gusts to nearly 50 knots.

SOURCE...Radar indicated.

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

Locations impacted include...
Pea Patch Island and Reedy Point. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3971 7558 3975 7556 3977 7551 3974 7545
      3969 7544 3961 7535 3951 7539 3950 7562
      3968 7562
TIME...MOT...LOC 2235Z 261DEG 42KT 3980 7571 3958 7578 

HAIL...0.00IN
WIND...49KTS

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 28, 2:39 AM EDT	Gale Warning	PHI		35 hr
Mar 28, 6:43 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Morris, Somerset, Warren	47 min
Mar 28, 6:47 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Mercer, Monmouth, Salem	43 min
Mar 28, 7:17 PM EDT	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Monmouth, Ocean, Somerset	60 min
Mar 28, 7:20 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Gloucester, Monmouth, Ocean	70 min
Mar 28, 7:38 PM EDT	Special Marine Warning	PHI		111 min
Mar 28, 5:04 PM EDT	Special Weather Statement	PHI	Berks	41 min
Mar 28, 5:13 PM EDT	Special Weather Statement	PHI	Carbon	32 min
Mar 28, 5:45 PM EDT	Special Weather Statement	PHI	Berks, Lehigh	30 min
Mar 28, 6:02 PM EDT	Special Weather Statement	PHI	Chester	28 min
Mar 28, 6:12 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery	48 min
Mar 28, 6:15 PM EDT	Special Weather Statement	PHI	Montgomery	30 min
Mar 28, 7:54 PM EDT	Special Weather Statement	PHI	Sussex	36 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.