Alert archive / Rhode Island / High Surf Advisories in 2021

High Surf Advisory 3, NWS Boston/Norton, MA

September 12, 2021Newport County, Washington County, Rhode Island; Dukes County, Nantucket County, Massachusetts

NWS Boston/Norton, MA issued this high surf advisory at Sep 12, 2021, 4:09 AM EDT for Newport County, Washington County, Rhode Island; Dukes County, Nantucket County, Massachusetts. It took effect at Sep 12, 2021, 7:00 AM EDT. It was in force for 12 hr.

The area

The counties it named.

The facts

Issued
Sep 12, 2021, 4:09 AM EDT (08:09 UTC)
In effect from
Sep 12, 2021, 7:00 AM EDT
Expired
Sep 12, 2021, 7:00 PM EDT
In force
12 hr
Issued by
NWS Boston/Norton, MA

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

The radar

The Boston radar (KBOX), 66 km from the middle of the area, began a volume at 08:13 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, 8.2 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 2021-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 25 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2021-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 98 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
25 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1019 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
98 m²/s²
0-3 km storm-relative helicity
134 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

411 
WHUS41 KBOX 120809
CFWBOX

Coastal Hazard Message
National Weather Service Boston/Norton MA
409 AM EDT Sun Sep 12 2021

MAZ023-024-RIZ006>008-122115-
/O.NEW.KBOX.SU.Y.0003.210912T1100Z-210912T2300Z/
Dukes MA-Nantucket MA-Washington RI-Newport RI-Block Island RI-
409 AM EDT Sun Sep 12 2021

...HIGH SURF ADVISORY IN EFFECT UNTIL 7 PM EDT THIS EVENING...

* WHAT...Large breaking waves of 4 to 7 feet expected in the 
  surf zone.

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

* WHEN...Until 7 PM EDT this evening.

* IMPACTS...Dangerous swimming and surfing conditions expected due
  to high surf and life threatening rip currents. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

Nearby

High Surf Advisories in Rhode Island, 2021High Surf Advisories in Massachusetts, 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.