Alert archive / Massachusetts / High Surf Advisories in 2021

High Surf Advisory 1, NWS Boston/Norton, MA

August 5, 2021Newport County, Washington County, Rhode Island; Bristol County, Dukes County, Nantucket County, Massachusetts

NWS Boston/Norton, MA issued this high surf advisory at Aug 5, 2021, 3:14 AM EDT for Newport County, Washington County, Rhode Island; Bristol County, Dukes County, Nantucket County, Massachusetts. It took effect at Aug 5, 2021, 6:00 AM EDT. It was in force for 14 hr.

The area

The counties it named.

The facts

Issued
Aug 5, 2021, 3:14 AM EDT (07:14 UTC)
In effect from
Aug 5, 2021, 6:00 AM EDT
Expired
Aug 5, 2021, 8:00 PM EDT
In force
14 hr
Issued by
NWS Boston/Norton, MA

Counties Bristol County, MA, Dukes County, MA, Nantucket County, MA, Newport County, RI, Washington County, RI

The radar

The Boston radar (KBOX), 57 km from the middle of the area, began a volume at 07:13 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 00:00Z, 7.2 hours before the alert went out and 174 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, Brookhaven, NY at 00:00Z on 2021-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Brookhaven, NY at 00:00Z on 2021-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
591 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

177 
WHUS41 KBOX 050714
CFWBOX

Coastal Hazard Message
National Weather Service Boston/Norton MA
314 AM EDT Thu Aug 5 2021

MAZ020-023-024-RIZ006>008-052015-
/O.NEW.KBOX.SU.Y.0001.210805T1000Z-210806T0000Z/
Southern Bristol MA-Dukes MA-Nantucket MA-Washington RI-
Newport RI-Block Island RI-
314 AM EDT Thu Aug 5 2021

...HIGH SURF ADVISORY IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Large breaking waves of 6 to 8 feet expected in the 
  surf zone.

* WHERE...In Massachusetts, Southern Bristol MA, Dukes MA and 
  Nantucket MA Counties. In Rhode Island, Washington RI, Newport 
  RI and Block Island RI Counties.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Dangerous swimming and surfing conditions expected. 
  Rip currents can sweep even the best swimmers away from shore 
  into deeper water.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced swimmers should remain out of the water due to
dangerous surf conditions.

&&

$$
2 follow-up statements
742 
WHUS41 KBOX 051848
CFWBOX

Coastal Hazard Message
National Weather Service Boston/Norton MA
248 PM EDT Thu Aug 5 2021

MAZ020-023-024-RIZ006>008-060000-
/O.CON.KBOX.SU.Y.0001.000000T0000Z-210806T0000Z/
Southern Bristol MA-Dukes MA-Nantucket MA-Washington RI-
Newport RI-Block Island RI-
248 PM EDT Thu Aug 5 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS
EVENING...

* WHAT...Large breaking waves of 6 to 8 feet expected in the 
  surf zone.

* WHERE...In Massachusetts, Southern Bristol MA, Dukes MA and 
  Nantucket MA Counties. In Rhode Island, Washington RI, Newport 
  RI and Block Island RI Counties.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Dangerous swimming and surfing conditions expected. 
  Rip currents can sweep even the best swimmers away from shore 
  into deeper water.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced swimmers should remain out of the water due to
dangerous surf conditions.

&&

$$
865 
WHUS41 KBOX 060003
CFWBOX

Coastal Hazard Message
National Weather Service Boston/Norton MA
803 PM EDT Thu Aug 5 2021

MAZ023-024-RIZ006>008-061315-
/O.EXP.KBOX.SU.Y.0001.000000T0000Z-210806T0000Z/
/O.NEW.KBOX.RP.S.0005.210806T1200Z-210807T0000Z/
Dukes MA-Nantucket MA-Washington RI-Newport RI-Block Island RI-
803 PM EDT Thu Aug 5 2021

...HIGH RIP CURRENT RISK IN EFFECT FROM 8 AM EDT FRIDAY THROUGH
FRIDAY EVENING...
...HIGH SURF ADVISORY HAS EXPIRED...

* WHAT...Dangerous rip currents expected.

* WHERE...In Massachusetts, Dukes MA and Nantucket MA Counties. 
  In Rhode Island, Washington RI, Newport RI and Block Island RI 
  Counties.

* WHEN...From 8 AM EDT Friday through Friday evening.

* IMPACTS...Rip currents can sweep even the best swimmers away 
  from shore into deeper water.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Swim near a lifeguard. If caught in a rip current, relax and
float. Don't swim against the current. If able, swim in a
direction following the shoreline. If unable to escape, face the
shore and call or wave for help.

&&

$$

MAZ020-060115-
/O.EXP.KBOX.SU.Y.0001.000000T0000Z-210806T0000Z/
Southern Bristol MA-
803 PM EDT Thu Aug 5 2021

...HIGH SURF ADVISORY HAS EXPIRED...

High surf conditions have lessened so the advisory has been allowed to expire. 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 12:12 AM EDTSpecial Weather StatementBOXBristol, Newport48 min
Aug 5, 5:27 AM EDTAreal Flood WarningBOXBristol, Kent, Newport, Providence, Washington7 hr
Aug 5, 6:52 AM EDTAreal Flood WarningBOXProvidence6 hr

Nearby

High Surf Advisories in Massachusetts, 2021High Surf Advisories in Rhode Island, 2021Every high surf advisory 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.