Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 88, NWS Philadelphia/Mount Holly

July 17, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Jul 17, 2021, 1:50 PM EDT. It was in force for 40 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: Jul 17, 2021, 1:50 PM EDT (17:50 UTC)
Expired: Jul 17, 2021, 2:30 PM EDT
In force: 40 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 34.0 mph

The radar

The Philadelphia radar (KDIX), 51 km from the middle of the area, began a volume at 17:51 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 5.8 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: 1203 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 1054 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

As transmitted.

956 
WHUS51 KPHI 171750
SMWPHI
ANZ450-451-171830-
/O.NEW.KPHI.MA.W.0088.210717T1750Z-210717T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
150 PM EDT Sat Jul 17 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  
Coastal waters from Sandy Hook to Little Egg Inlet NJ out 20 nm...

* Until 230 PM EDT.

* At 150 PM EDT, strong thunderstorms were located along a line
  extending from Atlantic Highlands to near Silverton, moving east at
  20 knots.

  HAZARD...Wind gusts 34 knots or greater and small hail.

  SOURCE...Radar.

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

* Locations impacted include...
  Sea Girt Reef, Leonardo, Atlantic Highlands, Monmouth Beach, Sea
  Bright, Axel Carlson Reef, Silverton, Fair Haven, Lavallette, Point
  Pleasant Beach, Belmar, Manasquan Inlet, Pine Beach and Sandy Hook
  Reef.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

&&

LAT...LON 4044 7398 4030 7373 3998 7377 3993 7420
      4012 7415 4020 7411 4024 7405 4027 7405
      4030 7410 4041 7407 4042 7406 4040 7398
      4042 7398 4042 7400
TIME...MOT...LOC 1750Z 262DEG 18KT 4039 7398 4005 7409 

HAIL...<.75IN
WIND...>34KTS

$$

JEO

1 follow-up statement

091 
FZUS71 KPHI 171821
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
221 PM EDT Sat Jul 17 2021

ANZ450-451-171831-
/O.EXP.KPHI.MA.W.0088.000000T0000Z-210717T1830Z/
221 PM EDT Sat Jul 17 2021

...THE SPECIAL MARINE WARNING WILL EXPIRE AT 230 PM EDT...

The affected areas were... 

Coastal waters from Sandy Hook to Little Egg Inlet NJ out 20 nm...

The thunderstorms have weakened and no longer pose a significant
threat to boaters.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
central and southern New Jersey...and the adjacent coastal waters.

LAT...LON 4044 7398 4030 7373 3998 7377 3993 7420
      4012 7415 4020 7411 4024 7405 4027 7405
      4030 7410 4041 7407 4042 7406 4040 7398
      4042 7398 4042 7400
TIME...MOT...LOC 1821Z 262DEG 18KT 4042 7367 4008 7378 

$$

JEO

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 12:55 PM EDT	Special Weather Statement	PHI	Hunterdon	50 min
Jul 17, 1:05 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer	40 min
Jul 17, 1:31 PM EDT	Areal Flood Advisory	PHI	Hunterdon	97 min
Jul 17, 1:56 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Morris, Somerset, Warren	36 min
Jul 17, 2:02 PM EDT	Areal Flood Advisory	PHI	Monmouth, Ocean	92 min
Jul 17, 2:56 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Somerset	49 min
Jul 17, 3:06 PM EDT	Severe Thunderstorm Warning	PHI	Warren	39 min
Jul 17, 3:09 PM EDT	Tornado Warning	PHI	Middlesex	21 min
Jul 17, 3:38 PM EDT	Areal Flood Advisory	PHI	Middlesex	40 min
Jul 17, 3:51 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex	24 min
Jul 17, 4:55 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Somerset	50 min
Jul 17, 5:13 PM EDT	Areal Flood Advisory	PHI	Hunterdon	4 hr
Jul 17, 5:19 PM EDT	Tornado Warning	PHI	Hunterdon	14 min
Jul 17, 5:25 PM EDT	Flash Flood Warning	PHI	Hunterdon	6 hr
Jul 17, 5:30 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	19 min
Jul 17, 5:52 PM EDT	Areal Flood Advisory	PHI	Somerset	2 hr
Jul 17, 6:02 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Somerset	43 min
Jul 17, 6:15 PM EDT	Flash Flood Warning	PHI	Morris, Somerset	5 hr
Jul 17, 6:39 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Morris, Somerset	51 min
Jul 17, 6:51 PM EDT	Severe Thunderstorm Warning	PHI	Burlington	39 min
Jul 17, 6:59 PM EDT	Small Craft Advisory	PHI		7 hr
Jul 17, 7:01 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Somerset	44 min
Jul 17, 7:12 PM EDT	Areal Flood Advisory	PHI	Mercer, Somerset	3 hr
Jul 17, 7:26 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Morris, Somerset	49 min
Jul 16, 8:14 PM EDT	Special Weather Statement	PHI	Montgomery	31 min
Jul 16, 8:41 PM EDT	Special Weather Statement	PHI	Bucks	34 min
Jul 16, 9:07 PM EDT	Special Weather Statement	PHI	Lehigh	23 min
Jul 16, 9:29 PM EDT	Special Weather Statement	PHI	Lehigh	31 min
Jul 16, 10:21 PM EDT	Special Weather Statement	PHI	Lehigh	24 min
Jul 17, 2:30 PM EDT	Special Weather Statement	PHI	Berks	45 min
Jul 17, 2:36 PM EDT	Severe Thunderstorm Warning	PHI	Berks	39 min
Jul 17, 7:36 PM EDT	Special Weather Statement	PHI	Carbon	54 min
Jul 17, 7:36 PM EDT	Special Weather Statement	PHI	Kent	39 min
Jul 17, 7:59 PM EDT	Severe Thunderstorm Warning	PHI	Kent	46 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.