Alert archive / Massachusetts / Special Weather Statements in 2021

Special Weather Statement, NWS Boston/Norton, MA

July 23, 2021Bristol County, Massachusetts

NWS Boston/Norton, MA issued this special weather statement at Jul 23, 2021, 5:23 PM EDT for Bristol County, Massachusetts. It was in force for 52 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: Jul 23, 2021, 5:23 PM EDT (21:23 UTC)
Expired: Jul 23, 2021, 6:15 PM EDT
In force: 52 min
Issued by: NWS Boston/Norton, MA

County Bristol County, MA

The radar

The Boston radar (KBOX), 19 km from the middle of the area, began a volume at 21:22 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, 9.4 hours before the alert went out and 175 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1463 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: -8 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

321 
WWUS81 KBOX 232123
SPSBOX

Special Weather Statement
National Weather Service Boston/Norton MA
523 PM EDT Fri Jul 23 2021
 
MAZ017-018-020-021-232215-
Southern Bristol MA-Northern Bristol MA-Southern Plymouth MA-
Western Plymouth MA-
523 PM EDT Fri Jul 23 2021

...STRONG THUNDERSTORM...

At 522 PM EDT, Doppler radar was tracking a strong thunderstorm over
Norton, or near Taunton, moving south at 15 mph.

Penny size hail and winds in excess of 40 mph will accompany this 
storm. Cloud to ground lightning and torrential downpours can be 
expcted from this storm.

Locations impacted include...
Fall River, Taunton, North Attleborough, Bridgewater, Attleboro,
Mansfield, Middleborough, Easton, Norton, Somerset, Swansea, Raynham,
Rehoboth, Lakeville, Freetown, Dighton, West Bridgewater, Berkley and
Rochester.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough to
produce minor damage, such as a few downed branches.

These storms may intensify and become capable of producing damage.
Stay tuned for updated statements and possible warnings.

&&

LAT...LON 4172 7116 4171 7119 4172 7120 4171 7121
      4173 7122 4174 7122 4200 7130 4206 7108
      4178 7088 4171 7116
TIME...MOT...LOC 2122Z 340DEG 11KT 4196 7116 

$$

Loconto

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 2:28 PM EDT	Special Weather Statement	BOX	Middlesex	32 min
Jul 23, 2:49 PM EDT	Coastal Flood Statement	BOX	Barnstable, Essex, Nantucket, Norfolk, Plymouth, Suffolk	11 hr
Jul 23, 3:04 PM EDT	Special Weather Statement	BOX	Essex	26 min
Jul 23, 3:28 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex, Suffolk	47 min
Jul 23, 3:29 PM EDT	Special Marine Warning	BOX		61 min
Jul 23, 4:41 PM EDT	Special Weather Statement	BOX	Essex	34 min
Jul 23, 4:57 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex	63 min
Jul 23, 5:50 PM EDT	Special Marine Warning	BOX		55 min
Jul 23, 6:09 PM EDT	Severe Thunderstorm Warning	BOX	Bristol, Plymouth	26 min
Jul 23, 6:25 PM EDT	Special Weather Statement	BOX	Plymouth	50 min
Jul 23, 6:32 PM EDT	Special Weather Statement	BOX	Worcester	43 min
Jul 23, 6:42 PM EDT	Severe Thunderstorm Warning	BOX	Bristol, Norfolk, Plymouth	48 min
Jul 23, 7:28 PM EDT	Severe Thunderstorm Warning	BOX	Plymouth	34 min
Jul 23, 4:48 PM EDT	Special Weather Statement	BOX	Bristol, Providence	42 min
Jul 23, 5:43 PM EDT	Special Weather Statement	BOX	Bristol, Newport	47 min
Jul 23, 1:20 PM EDT	Special Weather Statement	BOX		40 min

Nearby

Special Weather Statements in Massachusetts, 2021 Every special weather statement 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.