Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 68, NWS Boston/Norton, MA

July 23, 2011Norfolk County, Plymouth County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 23, 2011, 10:21 AM EDT for Norfolk County, Plymouth County, Massachusetts. It was in force for 39 min. 5 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
Jul 23, 2011, 10:21 AM EDT (14:21 UTC)
Expired
Jul 23, 2011, 11:00 AM EDT
In force
39 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

Counties Norfolk County, MA, Plymouth County, MA

The radar

The Boston radar (KBOX), 29 km from the middle of the area, began a volume at 14:24 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
Jul 23, 10:30 AM EDTTSTM WND DMGBrockton, MATREES AND WIRES DOWN IN SOUTH BROCKTON
Jul 23, 10:35 AM EDTTSTM WND GST 58Brockton, MAMEASURED AT HIGH SCHOOL
Jul 23, 10:42 AM EDTTSTM WND DMGBrockton, MATREES DOWN ON ROUTE 14 AT BROCKTON WHITMAN LINE
Jul 23, 10:50 AM EDTTSTM WND DMGBrockton, MATREES AND WIRES DOWN ON FRENCH AVENUE
Jul 23, 10:55 AM EDTTSTM WND DMGBrockton, MALIVE WIRES DOWN ON ASH STREET IN SW BROCKTON

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

The nearest sounding before it

Chatham, MA (KCHH), launched 12:00Z, 2.4 hours before the alert went out and 84 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, Chatham, MA at 12:00Z on 2011-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Chatham, MA at 12:00Z on 2011-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2396 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

973 
WUUS51 KBOX 231421
SVRBOX
MAC021-023-231500-
/O.NEW.KBOX.SV.W.0068.110723T1421Z-110723T1500Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
1021 AM EDT SAT JUL 23 2011

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL NORFOLK COUNTY IN EASTERN MASSACHUSETTS...
  NORTHERN PLYMOUTH COUNTY IN SOUTHEAST MASSACHUSETTS...
  THIS INCLUDES THE CITY OF BROCKTON...

* UNTIL 1100 AM EDT

* AT 1020 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR BROCKTON...AND WAS MOVING
  EAST AT 30 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE...ABINGTON...WHITMAN...
  ROCKLAND...HANSON...HANOVER...PEMBROKE AND MARSHFIELD.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND LARGE HAIL...AS WELL
AS DEADLY LIGHTNING AND TORRENTIAL RAIN. GET TO SAFE SHELTER NOW...
INSIDE A STURDY BUILDING OR IN A VEHICLE. DO NOT SEEK SHELTER UNDER
TREES. IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY
LIGHTNING. DRIVERS SHOULD BE ALERT FOR PONDING OF WATER AND AVOID
FLOODED ROADS.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT LIGHTNING WAS
OCCURRING WITH THIS STORM. GET INDOORS OR INSIDE A VEHICLE NOW! DO
NOT SEEK SHELTER UNDER TREES. IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

&&

LAT...LON 4201 7067 4205 7105 4214 7104 4215 7068
TIME...MOT...LOC 1421Z 271DEG 25KT 4209 7103

$$

THOMPSON
1 follow-up statement
393 
WWUS51 KBOX 231437
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
1037 AM EDT SAT JUL 23 2011

MAC021-023-231500-
/O.CON.KBOX.SV.W.0068.000000T0000Z-110723T1500Z/
NORFOLK MA-PLYMOUTH MA-
1037 AM EDT SAT JUL 23 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 AM EDT
FOR NORTHERN PLYMOUTH AND EAST CENTRAL NORFOLK COUNTIES...

AT 1033 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR WHITMAN AND 
BROCKTON...MOVING EAST AT 30 MPH. THERE HAS BEEN A REPORT OF DOWNED 
TREES AND WIRES IN THE SOUTH SIDE OF BROCKTON. THIS STORM HAS ALSO 
BEEN PRODUCING VERY FREQUENT LIGHTNING.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
HANSON...HANOVER...PEMBROKE AND MARSHFIELD.

THIS IS A DANGEROUS STORM WITH STRONG WINDS...FREQUENT CLOUD TO 
GROUND LIGHTNING AND VERY HEAVY DOWNPOURS. PEOPLE IN EXPOSED AREAS 
SUCH AS ON AREA BEACHES IN THE MARSHFIELD AND DUXBURY AREAS SHOULD 
SEEK INSIDE SHELTER FROM LIGHTNING NOW.

LAT...LON 4201 7067 4205 7105 4214 7104 4215 7068
TIME...MOT...LOC 1435Z 271DEG 25KT 4209 7090

$$

THOMPSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 3:38 AM EDTHeat AdvisoryBOXBristol, Hampden, Hampshire, Middlesex, Norfolk, Plymouth and 2 more13 hr
Jul 23, 4:58 AM EDTSpecial Weather StatementBOXFranklin32 min
Jul 23, 6:36 AM EDTSpecial Weather StatementBOXMiddlesex24 min
Jul 23, 6:39 AM EDTSpecial Weather StatementBOXFranklin36 min
Jul 23, 6:52 AM EDTSpecial Weather StatementBOXFranklin23 min
Jul 23, 7:29 AM EDTSpecial Weather StatementBOXWorcester31 min
Jul 23, 8:15 AM EDTSpecial Weather StatementBOXMiddlesex, Norfolk, Suffolk45 min
Jul 23, 9:14 AM EDTSpecial Weather StatementBOXNorfolk46 min
Jul 23, 9:45 AM EDTSpecial Weather StatementBOXSuffolk45 min
Jul 23, 10:00 AM EDTSpecial Weather StatementBOXNorfolk45 min
Jul 23, 10:14 AM EDTSpecial Marine WarningBOX26 min
Jul 23, 10:45 AM EDTSpecial Marine WarningBOX45 min
Jul 23, 10:50 AM EDTSevere Thunderstorm WarningBOXPlymouth55 min
Jul 23, 11:02 AM EDTSevere Thunderstorm WarningBOXPlymouth28 min
Jul 23, 11:16 AM EDTSpecial Marine WarningBOX59 min
Jul 23, 11:28 AM EDTSpecial Marine WarningBOX62 min
Jul 23, 11:38 AM EDTSpecial Weather StatementBOXPlymouth37 min
Jul 23, 11:56 AM EDTSpecial Weather StatementBOXBristol64 min
Jul 23, 12:00 PM EDTSpecial Marine WarningBOX30 min
Jul 23, 12:15 PM EDTSpecial Marine WarningBOX45 min
Jul 23, 12:20 PM EDTSpecial Weather StatementBOXPlymouth40 min
Jul 23, 12:32 PM EDTSpecial Marine WarningBOX43 min
Jul 23, 12:46 PM EDTSpecial Marine WarningBOX32 min
Jul 23, 1:01 PM EDTSevere Thunderstorm WarningBOXBarnstable, Dukes29 min
Jul 23, 1:09 PM EDTSpecial Marine WarningBOX51 min
Jul 23, 1:32 PM EDTSevere Thunderstorm WarningBOXNantucket43 min
Jul 23, 1:44 PM EDTSpecial Marine WarningBOX61 min
Jul 23, 2:07 PM EDTSpecial Marine WarningBOX38 min
Jul 23, 2:14 PM EDTSpecial Weather StatementBOXBarnstable31 min
Jul 23, 2:29 PM EDTSpecial Marine WarningBOX31 min
Jul 23, 2:51 PM EDTSpecial Marine WarningBOX39 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2011Every severe thunderstorm warning in 2011

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.