Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 1, NWS Philadelphia/Mount Holly

January 20, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Jan 20, 2021, 12:02 PM EST. It was in force for 58 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: Jan 20, 2021, 12:02 PM EST (17:02 UTC)
Expired: Jan 20, 2021, 1:00 PM EST
In force: 58 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.0 in
Wind: 40.0 mph

The radar

The Philadelphia radar (KDIX), 30 km from the middle of the area, began a volume at 17:02 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
Jan 20, 12:30 PM EST	MARINE TSTM WIND 48	5 Se Mystic Island, NJ	MEASURED AT TKTN4 HADS SITE AT LITTLE EGG INLET.
Jan 20, 12:36 PM EST	MARINE TSTM WIND 40	Barnegat Light, NJ	MEASURED AT BGLN4 HADS SITE ON BARNEGAT LIGHT.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 5.0 hours before the alert went out and 150 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: 1247 m above ground
0-6 km bulk shear: 74 kt
0-1 km storm-relative helicity: -7 m²/s²
0-3 km storm-relative helicity: 195 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

238 
WHUS51 KPHI 201702
SMWPHI
ANZ450>452-470>472-201800-
/O.NEW.KPHI.MA.W.0001.210120T1702Z-210120T1800Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
1202 PM EST Wed Jan 20 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  
Coastal and outer waters from Sandy Hook to Great Egg Inlet NJ...

* Until 100 PM EST.

* At 1202 PM EST, rain/snow showers were located along a line 
  extending from near Rockaway Inlet to 10 nm northwest of Silverton 
  to 29 nm northwest of Little Egg Inlet, moving east at 30 knots.

  HAZARD...Wind gusts to 40 knots.

  SOURCE...Radar.

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

* Locations impacted include...
  Sea Girt Reef, Ship Bottom, Atlantic Highlands, Garden State South
  Reef, Axel Carlson Reef, Silverton, Harvey Cedars, Lavallette,
  Barnegat Light, North Beach Haven, Point Pleasant Beach, Seaside
  Park, Brigantine, Ocean Gate, Little Egg Reef, Barnegat Light Reef,
  Monmouth Beach, Sea Bright, Forked River and Fair Haven.

LAT...LON 4024 7363 3982 7331 3960 7332 3922 7354
      3931 7423 3946 7452 3948 7450 3956 7459
      3962 7455 3960 7439 3970 7426 3982 7427
      3990 7420 3996 7425 4020 7411 4024 7405
      4033 7413 4042 7404 4040 7398 4044 7399
TIME...MOT...LOC 1702Z 290DEG 29KT 4054 7387 4010 7432 3976 7486 

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

$$

NC

The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 20, 9:52 AM EST	Special Weather Statement	PHI	Hunterdon, Somerset, Warren	53 min
Jan 20, 10:42 AM EST	Special Weather Statement	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset	63 min
Jan 20, 1:00 PM EST	Special Marine Warning	PHI		65 min
Jan 20, 8:56 AM EST	Special Weather Statement	PHI	Carbon, Monroe	49 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.