Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 14, NWS Boston/Norton, MA

June 8, 20214 counties in Massachusetts; Providence County, Rhode Island

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jun 8, 2021, 5:17 PM EDT for 4 counties in Massachusetts; Providence County, Rhode Island. It was in force for 58 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 8, 2021, 5:17 PM EDT (21:17 UTC)
Expired
Jun 8, 2021, 6:15 PM EDT
In force
58 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Bristol County, MA, Middlesex County, MA, Norfolk County, MA, Worcester County, MA, Providence County, RI

The radar

The Boston radar (KBOX), 32 km from the middle of the area, began a volume at 21:20 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.

What was reported inside it

TimeReportWhereRemark
Jun 8, 5:40 PM EDTTSTM WND DMGBellingham, MATREE DOWN ON TWO CARS AT NORTH ST
Jun 8, 5:45 PM EDTTSTM WND DMGFranklin, MAPOWER LINE DOWN ON LINCOLN ST

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.3 hours before the alert went out and 176 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 2021-06-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 740 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 2021-06-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 square meters per square second.1939Sfc1 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
740 J/kg
Mixed-layer CIN
-106 J/kg
Mixed-layer LCL
1004 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

489 
WUUS51 KBOX 082117
SVRBOX
MAC005-017-021-027-RIC007-082215-
/O.NEW.KBOX.SV.W.0014.210608T2117Z-210608T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
517 PM EDT Tue Jun 8 2021

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Southwestern Norfolk County in eastern Massachusetts...
  Southeastern Worcester County in central Massachusetts...
  South central Middlesex County in northeastern Massachusetts...
  Northwestern Bristol County in southeastern Massachusetts...
  North central Providence County in Rhode Island...

* Until 615 PM EDT.

* At 517 PM EDT, a severe thunderstorm was located over Millville, or
  near Woonsocket, moving east at 20 mph.

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

  SOURCE...Radar indicated.

  IMPACT...Expect wind damage to trees and power lines. Minor hail 
           damage to vehicles is possible.

* Locations impacted include...
  Woonsocket, Cumberland, Franklin, North Attleborough, Milford,
  Walpole, Mansfield, Norton, Sharon, Foxborough, Bellingham,
  Burrillville, Northbridge, Westwood, Holliston, Uxbridge, Medway,
  Medfield, North Smithfield and Norfolk.

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.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4198 7167 4213 7172 4225 7126 4200 7116
TIME...MOT...LOC 2117Z 257DEG 19KT 4205 7159 

HAIL...1.00IN
WIND...60MPH
 
$$

Chai
2 follow-up statements
978 
WWUS51 KBOX 082140
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
540 PM EDT Tue Jun 8 2021

MAC005-017-021-027-RIC007-082215-
/O.CON.KBOX.SV.W.0014.000000T0000Z-210608T2215Z/
Norfolk MA-Worcester MA-Middlesex MA-Bristol MA-Providence RI-
540 PM EDT Tue Jun 8 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR SOUTHWESTERN NORFOLK...SOUTHEASTERN WORCESTER...SOUTH CENTRAL
MIDDLESEX...NORTHWESTERN BRISTOL AND NORTH CENTRAL PROVIDENCE
COUNTIES...

At 539 PM EDT, a severe thunderstorm was located over Franklin, 
moving east at 20 mph. Up to 25 percent of customers without power 
in Mendon and Bellingham, MA as of 530 PM EDT. 

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

SOURCE...Radar indicated.

IMPACT...Expect wind damage to trees and power lines. Minor hail 
         damage to vehicles is possible.

Locations impacted include...
Woonsocket, Cumberland, Franklin, North Attleborough, Milford,
Walpole, Mansfield, Norton, Sharon, Foxborough, Bellingham, Westwood,
Holliston, Medway, Medfield, North Smithfield, Norfolk, Wrentham,
Blackstone and Plainville.

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.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4199 7154 4216 7159 4225 7126 4200 7116
TIME...MOT...LOC 2139Z 257DEG 19KT 4208 7144 

HAIL...1.00IN
WIND...60MPH
 
$$

Chai
357 
WWUS51 KBOX 082150
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
550 PM EDT Tue Jun 8 2021

MAC027-RIC007-082159-
/O.CAN.KBOX.SV.W.0014.000000T0000Z-210608T2215Z/
Worcester MA-Providence RI-
550 PM EDT Tue Jun 8 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN WORCESTER AND
NORTH CENTRAL PROVIDENCE 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 4202 7142 4216 7148 4225 7126 4202 7117
TIME...MOT...LOC 2149Z 257DEG 19KT 4209 7137 

$$

MAC005-017-021-082215-
/O.CON.KBOX.SV.W.0014.000000T0000Z-210608T2215Z/
Norfolk MA-Middlesex MA-Bristol MA-
550 PM EDT Tue Jun 8 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR SOUTHWESTERN NORFOLK...SOUTH CENTRAL MIDDLESEX AND NORTHWESTERN
BRISTOL COUNTIES...

At 549 PM EDT, a severe thunderstorm was located over Franklin, 
moving east at 20 mph. Amateur radio reported tree down on cars in 
Bellingham, MA at 540 PM EDT. 

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

SOURCE...Radar indicated.

IMPACT...Expect wind damage to trees and power lines. Minor hail 
         damage to vehicles is possible.

Locations impacted include...
Franklin, Walpole, Mansfield, Sharon, Foxborough, Bellingham,
Westwood, Holliston, Medway, Medfield, Norfolk, Wrentham, Plainville,
Millis, Dover and Sherborn.

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.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4202 7142 4216 7148 4225 7126 4202 7117
TIME...MOT...LOC 2149Z 257DEG 19KT 4209 7137 

HAIL...1.00IN
WIND...60MPH
 
$$

Chai

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 8, 12:35 PM EDTSpecial Weather StatementBOXHampshire40 min
Jun 8, 12:54 PM EDTFlash Flood WatchBOXFranklin, Hampden, Hampshire, Middlesex, Worcester8 hr
Jun 8, 1:02 PM EDTFlash Flood WarningBOXHampshire55 min
Jun 8, 1:13 PM EDTSpecial Weather StatementBOXHampden47 min
Jun 8, 1:34 PM EDTSevere Thunderstorm WarningBOXHampden, Hampshire41 min
Jun 8, 1:39 PM EDTFlash Flood WarningBOXHampden, Hampshire67 min
Jun 8, 2:40 PM EDTSpecial Weather StatementBOXHampshire50 min
Jun 8, 2:56 PM EDTSevere Thunderstorm WarningBOXHampden43 min
Jun 8, 3:09 PM EDTSpecial Weather StatementBOXWorcester51 min
Jun 8, 3:12 PM EDTSpecial Weather StatementBOXEssex48 min
Jun 8, 3:32 PM EDTSpecial Marine WarningBOX43 min
Jun 8, 3:37 PM EDTSpecial Weather StatementBOXHampshire38 min
Jun 8, 3:42 PM EDTSpecial Weather StatementBOXEssex48 min
Jun 8, 3:51 PM EDTSpecial Weather StatementBOXHampshire39 min
Jun 8, 3:52 PM EDTSpecial Marine WarningBOX53 min
Jun 8, 4:02 PM EDTSpecial Weather StatementBOXNorfolk43 min
Jun 8, 4:04 PM EDTSpecial Weather StatementBOXHampshire41 min
Jun 8, 4:13 PM EDTSpecial Weather StatementBOXEssex47 min
Jun 8, 4:38 PM EDTSpecial Marine WarningBOX52 min
Jun 8, 5:33 PM EDTSpecial Marine WarningBOX42 min
Jun 8, 5:59 PM EDTSevere Thunderstorm WarningBOXBristol, Norfolk, Plymouth, Suffolk35 min
Jun 8, 4:52 PM EDTSpecial Weather StatementBOXProvidence38 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.