Alert archive / Massachusetts / Special Marine Warnings in 2021

Special Marine Warning 13, NWS Boston/Norton, MA

June 22, 2021

NWS Boston/Norton, MA issued this special marine warning at Jun 22, 2021, 3:07 PM EDT. It was in force for 53 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
Jun 22, 2021, 3:07 PM EDT (19:07 UTC)
Expired
Jun 22, 2021, 4:00 PM EDT
In force
53 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Hail
0.75 in
Wind
49.0 mph

The radar

The Boston radar (KBOX), 49 km from the middle of the area, began a volume at 19:07 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

Gray, ME (KGYX), launched 12:00Z, 7.1 hours before the alert went out and 191 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, Gray, ME at 12:00Z on 2021-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 47 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, Gray, ME at 12:00Z on 2021-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -37 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
47 J/kg
Mixed-layer CIN
-102 J/kg
Mixed-layer LCL
851 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
-37 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

953 
WHUS51 KBOX 221907
SMWBOX
ANZ250-251-222000-
/O.NEW.KBOX.MA.W.0013.210622T1907Z-210622T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Boston/Norton MA
307 PM EDT Tue Jun 22 2021

The National Weather Service in Boston/Norton has issued a

* Special Marine Warning for...
  Coastal waters east of Ipswich Bay and the Stellwagen Bank National
  Marine Sanctuary...
  Massachusetts Bay and Ipswich Bay...

* Until 400 PM EDT.

* At 307 PM EDT, a strong thunderstorm was located near Patience
  Island, moving northeast at 35 knots.

  HAZARD...Wind gusts to nearly 50 knots and small hail.

  SOURCE...Radar.

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

* Locations impacted include...
  Boston Buoy 44013, Duxbury Pier Light, The Coastal Waters East Of
  Boston Harbor, Scituate Harbor, Minot Light, Green Harbor, Ocean
  Bluff-Brant Rock and Gurnet Point.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

&&

LAT...LON 4249 7059 4222 7002 4197 7069 4200 7073
      4202 7069 4211 7068 4215 7075 4221 7074
      4225 7082
TIME...MOT...LOC 1907Z 237DEG 36KT 4198 7089 

HAIL...<.75IN
WIND...49KTS

$$

BL
1 follow-up statement
256 
FZUS71 KBOX 221934
MWSBOX

Marine Weather Statement
National Weather Service Boston/Norton MA
334 PM EDT Tue Jun 22 2021

ANZ250-251-222000-
/O.CON.KBOX.MA.W.0013.000000T0000Z-210622T2000Z/
334 PM EDT Tue Jun 22 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 400 PM EDT...

For the following areas...
Coastal waters east of Ipswich Bay and the Stellwagen Bank National
Marine Sanctuary...
Massachusetts Bay and Ipswich Bay...

At 334 PM EDT, a strong thunderstorm was located 8 nm northeast of
Ocean Bluff-Brant Rock, moving northeast at 45 knots.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Boston Buoy 44013, The Coastal Waters East Of Boston Harbor, Scituate
Harbor, Green Harbor and Ocean Bluff-Brant Rock.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

&&

LAT...LON 4249 7059 4222 7002 4200 7061 4202 7064
      4211 7068 4215 7075 4216 7075 4221 7074
      4223 7075
TIME...MOT...LOC 1934Z 236DEG 46KT 4217 7050 

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

$$

BL

The office that day

Everything else NWS Boston/Norton, MA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 21, 10:50 PM EDTSpecial Weather StatementBOXFranklin40 min
Jun 22, 3:38 AM EDTRip Current StatementBOXDukes, Nantucket15 hr
Jun 22, 1:52 PM EDTSevere Thunderstorm WarningBOXBristol38 min
Jun 22, 2:00 PM EDTSevere Thunderstorm WarningBOXBristol, Norfolk, Plymouth, Suffolk45 min
Jun 22, 2:14 PM EDTSpecial Marine WarningBOX31 min
Jun 22, 2:33 PM EDTSpecial Weather StatementBOXPlymouth42 min
Jun 22, 2:43 PM EDTSpecial Weather StatementBOXPlymouth32 min
Jun 22, 3:06 PM EDTSevere Thunderstorm WarningBOXBristol, Plymouth23 min
Jun 22, 3:41 PM EDTSpecial Marine WarningBOX64 min
Jun 22, 4:42 PM EDTSpecial Weather StatementBOXNorfolk, Suffolk48 min
Jun 22, 1:39 PM EDTSpecial Weather StatementBOXBristol51 min
Jun 22, 1:41 PM EDTSpecial Weather StatementBOXBristol, Kent, Providence49 min

Nearby

Special Marine Warnings in Massachusetts, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.