Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 70, NWS Boston/Norton, MA

July 16, 2021Norfolk County, Worcester County, Massachusetts; Northeastern Connecticut Planning Region, Connecticut; Providence County, Rhode Island

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 16, 2021, 3:04 PM EDT for Norfolk County, Worcester County, Massachusetts; Northeastern Connecticut Planning Region, Connecticut; Providence County, Rhode Island. It was in force for 56 min. 1 report 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: Jul 16, 2021, 3:04 PM EDT (19:04 UTC)
Expired: Jul 16, 2021, 4:00 PM EDT
In force: 56 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Northeastern Connecticut Planning Region, CT, Norfolk County, MA, Worcester County, MA, Providence County, RI

The radar

The Boston radar (KBOX), 56 km from the middle of the area, began a volume at 19:06 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

Time	Report	Where	Remark
Jul 16, 3:15 PM EDT	TSTM WND DMG	Thompson, CT	TREES AND WIRES DOWN ON RIVERSIDE DRIVE AND WOODSTOCK ROAD.

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, 7.1 hours before the alert went out and 152 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1044 J/kg
Mixed-layer CIN: -56 J/kg
Mixed-layer LCL: 994 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 108 m²/s²
0-3 km storm-relative helicity: 105 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

860 
WUUS51 KBOX 161904
SVRBOX
CTC015-MAC021-027-RIC007-162000-
/O.NEW.KBOX.SV.W.0070.210716T1904Z-210716T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
304 PM EDT Fri Jul 16 2021

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Northeastern Windham County in northern Connecticut...
  Southwestern Norfolk County in eastern Massachusetts...
  Southeastern Worcester County in central Massachusetts...
  Northern Providence County in Rhode Island...

* Until 400 PM EDT.

* At 303 PM EDT, a severe thunderstorm was located near Thompson, or
  19 miles south of Worcester, moving east at 25 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, Smithfield, Lincoln, Central
  Falls, Webster, Southbridge, Bellingham, Burrillville, Uxbridge,
  North Smithfield, Dudley, Wrentham, Glocester, Putnam, Thompson,
  Blackstone, Douglas and Woodstock.

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 4194 7209 4204 7210 4209 7139 4188 7139
TIME...MOT...LOC 1903Z 269DEG 21KT 4200 7193 

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

Gaucher/Nocera

1 follow-up statement

286 
WWUS51 KBOX 161935
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
335 PM EDT Fri Jul 16 2021

CTC015-MAC021-027-RIC007-162000-
/O.CON.KBOX.SV.W.0070.000000T0000Z-210716T2000Z/
Windham CT-Norfolk MA-Worcester MA-Providence RI-
335 PM EDT Fri Jul 16 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR NORTHEASTERN WINDHAM...SOUTHWESTERN NORFOLK...SOUTHEASTERN
WORCESTER AND NORTHERN PROVIDENCE COUNTIES...

At 334 PM EDT, a severe thunderstorm was located over Burrillville,
or 9 miles west of Woonsocket, moving east at 25 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, Smithfield, Lincoln, Central Falls,
Webster, Bellingham, Burrillville, Uxbridge, North Smithfield,
Dudley, Wrentham, Glocester, Putnam, Thompson, Blackstone, Douglas,
Woodstock and Mendon.

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 4193 7195 4205 7194 4209 7139 4188 7139
TIME...MOT...LOC 1934Z 269DEG 21KT 4200 7168 

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

Gaucher/Nocera

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 16, 9:38 AM EDT	Heat Advisory	BOX	Bristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk	9 hr
Jul 16, 2:59 PM EDT	Flash Flood Watch	BOX	Franklin, Hampden, Hampshire, Worcester	56 hr
Jul 16, 3:41 PM EDT	Special Weather Statement	BOX	Hampden	49 min
Jul 16, 4:26 PM EDT	Special Weather Statement	BOX	Norfolk, Suffolk	49 min
Jul 16, 4:36 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Norfolk, Worcester	35 min
Jul 16, 4:50 PM EDT	Special Marine Warning	BOX		55 min
Jul 16, 5:05 PM EDT	Severe Thunderstorm Warning	BOX	Hampden, Worcester	55 min
Jul 16, 5:47 PM EDT	Severe Thunderstorm Warning	BOX	Bristol, Middlesex, Norfolk, Plymouth, Suffolk, Worcester	33 min
Jul 16, 6:32 PM EDT	Special Marine Warning	BOX		43 min
Jul 16, 5:14 PM EDT	Special Weather Statement	BOX		46 min
Jul 16, 5:31 PM EDT	Severe Thunderstorm Warning	BOX	Capitol Planning Region, Northeastern Connecticut Planning Region	42 min
Jul 16, 6:17 PM EDT	Special Weather Statement	BOX	Bristol, Kent, Providence	58 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2021 Severe Thunderstorm Warnings in Connecticut, 2021 Severe Thunderstorm Warnings in Rhode Island, 2021 Every 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.