Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 120, NWS Boston/Norton, MA

September 28, 2021Bristol County, Newport County, Washington County, Rhode Island; 4 counties in Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Sep 28, 2021, 2:07 PM EDT for Bristol County, Newport County, Washington County, Rhode Island; 4 counties in Massachusetts. 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
Sep 28, 2021, 2:07 PM EDT (18:07 UTC)
Expired
Sep 28, 2021, 3:00 PM EDT
In force
53 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Barnstable County, MA, Bristol County, MA, Dukes County, MA, Plymouth County, MA, Bristol County, RI, Newport County, RI, Washington County, RI

The radar

The Boston radar (KBOX), 46 km from the middle of the area, began a volume at 18:09 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, 6.1 hours before the alert went out and 173 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 12:00Z on 2021-09-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 116 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, Brookhaven, NY at 12:00Z on 2021-09-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 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
116 J/kg
Mixed-layer CIN
-338 J/kg
Mixed-layer LCL
1298 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
118 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

022 
WUUS51 KBOX 281807
SVRBOX
MAC001-005-007-023-RIC001-005-009-281900-
/O.NEW.KBOX.SV.W.0120.210928T1807Z-210928T1900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
207 PM EDT Tue Sep 28 2021

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Northwestern Dukes County in southeastern Massachusetts...
  Southwestern Barnstable County in southeastern Massachusetts...
  Southeastern Plymouth County in southeastern Massachusetts...
  Southeastern Bristol County in southeastern Massachusetts...
  Northeastern Washington County in Rhode Island...
  Newport County in Rhode Island...
  Southeastern Bristol County in Rhode Island...

* Until 300 PM EDT.

* At 207 PM EDT, a severe thunderstorm was located over Newport,
  moving northeast at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to trees and power lines.

* Locations impacted include...
  New Bedford, Fall River, Plymouth, Barnstable, Dartmouth, Falmouth,
  Newport, Bristol, Marion, Middleborough, Wareham, Sandwich, Bourne,
  Portsmouth, Middletown, Fairhaven, Tiverton, Westport, Mashpee and
  Carver.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4142 7094 4151 7099 4146 7119 4164 7122
      4148 7124 4145 7134 4157 7137 4152 7132
      4152 7131 4156 7131 4161 7142 4188 7060
      4161 7038 4144 7084 4154 7065 4175 7063
      4174 7071 4144 7085 4141 7095
TIME...MOT...LOC 1807Z 243DEG 37KT 4146 7127 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RM
1 follow-up statement
845 
WWUS51 KBOX 281823
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
223 PM EDT Tue Sep 28 2021

RIC001-009-281832-
/O.CAN.KBOX.SV.W.0120.000000T0000Z-210928T1900Z/
Washington RI-Bristol RI-
223 PM EDT Tue Sep 28 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN WASHINGTON AND
SOUTHEASTERN BRISTOL COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4142 7094 4151 7099 4146 7119 4164 7122
      4188 7060 4161 7038 4144 7084 4154 7065
      4175 7063 4174 7071 4144 7085 4141 7095
TIME...MOT...LOC 1822Z 243DEG 37KT 4153 7108 

$$

MAC001-005-007-023-RIC005-281900-
/O.CON.KBOX.SV.W.0120.000000T0000Z-210928T1900Z/
Dukes MA-Barnstable MA-Plymouth MA-Bristol MA-Newport RI-
223 PM EDT Tue Sep 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR NORTHWESTERN DUKES...SOUTHWESTERN BARNSTABLE...SOUTHEASTERN
PLYMOUTH...SOUTHEASTERN BRISTOL AND EASTERN NEWPORT COUNTIES...

At 222 PM EDT, a severe thunderstorm was located near Westport, or
near Dartmouth, moving northeast at 45 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to trees and power lines.

Locations impacted include...
New Bedford, Fall River, Plymouth, Barnstable, Dartmouth, Falmouth,
Marion, Wareham, Sandwich, Bourne, Fairhaven, Tiverton, Westport,
Mashpee, Carver, Acushnet, Freetown, Mattapoisett, Rochester and
Little Compton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4142 7094 4151 7099 4146 7119 4164 7122
      4188 7060 4161 7038 4144 7084 4154 7065
      4175 7063 4174 7071 4144 7085 4141 7095
TIME...MOT...LOC 1822Z 243DEG 37KT 4153 7108 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RM

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 28, 9:11 AM EDTSpecial Weather StatementBOXProvidence49 min
Sep 28, 9:29 AM EDTSevere Thunderstorm WarningBOXProvidence61 min
Sep 28, 10:50 AM EDTSpecial Weather StatementBOXProvidence40 min
Sep 28, 11:18 AM EDTSpecial Weather StatementBOXBristol42 min
Sep 28, 1:36 PM EDTSpecial Weather StatementBOXNewport, Washington39 min
Sep 28, 10:02 AM EDTSevere Thunderstorm WarningBOXMiddlesex, Norfolk, Plymouth, Suffolk43 min
Sep 28, 10:06 AM EDTSpecial Marine WarningBOX54 min
Sep 28, 11:42 AM EDTSpecial Marine WarningBOX48 min
Sep 28, 1:58 PM EDTSpecial Marine WarningBOX47 min
Sep 28, 2:30 PM EDTSpecial Marine WarningBOX45 min
Sep 28, 2:58 PM EDTSpecial Weather StatementBOXBarnstable47 min
Sep 28, 3:25 PM EDTSmall Craft AdvisoryBOX28 hr
Sep 28, 3:29 PM EDTSpecial Marine WarningBOX46 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2021Severe Thunderstorm Warnings in Rhode Island, 2021Every severe thunderstorm 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.