Alert archive / Massachusetts / Tornado Warnings in 2015

Tornado Warning 9, NWS Boston/Norton, MA

August 4, 2015Middlesex County, Massachusetts

NWS Boston/Norton, MA issued this tornado warning at Aug 4, 2015, 2:28 PM EDT for Middlesex County, Massachusetts. It was in force for 32 min. 11 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
Aug 4, 2015, 2:28 PM EDT (18:28 UTC)
Expired
Aug 4, 2015, 3:00 PM EDT
In force
32 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

County Middlesex County, MA

The radar

The Boston radar (KBOX), 67 km from the middle of the area, began a volume at 18:29 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
Aug 4, 2:34 PM EDTHAIL 1Acton, MA
Aug 4, 2:35 PM EDTHAIL 2Littleton, MA
Aug 4, 2:37 PM EDTHAIL 1Westford, MA
Aug 4, 2:40 PM EDTTSTM WND DMGLittleton, MATREE DOWN DAHLIA DRIVE
Aug 4, 2:40 PM EDTTSTM WND DMGLittleton, MATREE DOWN ON DAHLIA DRIVE
Aug 4, 2:42 PM EDTTSTM WND DMGLittleton, MAWIRES DOWN GRAY ROAD
Aug 4, 2:42 PM EDTTSTM WND DMGLittleton, MAWIRES DOWN ON GRAY ROAD
Aug 4, 2:46 PM EDTTSTM WND DMGLittleton, MAMULTIPLE TREES DOWN ON FOSTER STREET AND NAGOG HILL ROAD
Aug 4, 2:46 PM EDTTSTM WND DMGLittleton, MAMULTIPLE TREES DOWN ON FOSTER STREET AND NAGOG ROAD
Aug 4, 2:46 PM EDTTSTM WND DMGLittleton, MATREES DOWN ON MANNION PLACE...LARGE TREE DOWN ON ADAMS STREET
Aug 4, 3:03 PM EDTTSTM WND DMGWest Acton, MATREE DOWN...LARGE LIMBS DOWN...TREE ON CAR ON NEAR ROUTE 111. SHINGLES BLOWN OFF SIDE OF ROOF.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 4, 12:18 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Chatham, MA (KCHH), launched 12:00Z, 6.5 hours before the alert went out and 150 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 2015-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1622 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, Chatham, MA at 12:00Z on 2015-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 square meters per square second.1939587897Sfc1 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
1622 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
628 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
131 m²/s²
Significant tornado parameter
0.8
Supercell composite
4.2

Open this sounding in Storm Lab

The text

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

867 
WFUS51 KBOX 041828
TORBOX
MAC017-041900-
/O.NEW.KBOX.TO.W.0009.150804T1828Z-150804T1900Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
228 PM EDT TUE AUG 4 2015

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL MIDDLESEX COUNTY IN NORTHEASTERN MASSACHUSETTS...

* UNTIL 300 PM EDT
    
* AT 228 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED 
  OVER LITTLETON...OR NEAR CHELMSFORD...AND WAS MOVING EAST AT 35 
  MPH.

* SOME LOCATIONS IMPACTED INCLUDE...
  LOWELL...BILLERICA...CHELMSFORD...TEWKSBURY...BURLINGTON...
  WESTFORD...ACTON...CONCORD...BEDFORD...LITTLETON...AYER...
  BOXBOROUGH AND CARLISLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! DO NOT WAIT TO SEE THE TORNADO. GO TO A BASEMENT OR
INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING...AWAY FROM
WINDOWS. IF IN A VEHICLE...A MOBILE HOME OR OUTDOORS...GET TO THE
CLOSEST SHELTER. PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4250 7122 4247 7151 4256 7155 4265 7130
TIME...MOT...LOC 1828Z 256DEG 36KT 4253 7147 
$$

KJC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 4:11 AM EDTSpecial Weather StatementBOXFranklin, Hampshire64 min
Aug 4, 6:09 AM EDTSevere Thunderstorm WarningBOXBristol, Norfolk, Plymouth66 min
Aug 4, 6:13 AM EDTSpecial Marine WarningBOX62 min
Aug 4, 6:53 AM EDTSevere Thunderstorm WarningBOXBarnstable, Bristol, Norfolk, Plymouth52 min
Aug 4, 6:54 AM EDTSevere Thunderstorm WarningBOXBristol, Plymouth51 min
Aug 4, 6:55 AM EDTSpecial Marine WarningBOX65 min
Aug 4, 7:01 AM EDTSpecial Marine WarningBOX89 min
Aug 4, 7:15 AM EDTSevere Thunderstorm WarningBOXBarnstable60 min
Aug 4, 7:48 AM EDTSpecial Weather StatementBOXEssex42 min
Aug 4, 7:54 AM EDTSpecial Marine WarningBOX66 min
Aug 4, 8:06 AM EDTSevere Thunderstorm WarningBOXEssex24 min
Aug 4, 8:15 AM EDTSpecial Marine WarningBOX60 min
Aug 4, 12:32 PM EDTSpecial Weather StatementBOXFranklin43 min
Aug 4, 12:41 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester64 min
Aug 4, 1:21 PM EDTSpecial Weather StatementBOXHampshire54 min
Aug 4, 1:28 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire47 min
Aug 4, 1:35 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Worcester40 min
Aug 4, 1:57 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire63 min
Aug 4, 2:05 PM EDTSpecial Weather StatementBOXHampden, Hampshire40 min
Aug 4, 2:07 PM EDTTornado WarningBOXMiddlesex, Worcester23 min
Aug 4, 2:17 PM EDTSevere Thunderstorm WarningBOXHampden, Hampshire, Worcester58 min
Aug 4, 2:25 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester65 min
Aug 4, 2:39 PM EDTTornado WarningBOXFranklin, Worcester46 min
Aug 4, 2:47 PM EDTSpecial Marine WarningBOX58 min
Aug 4, 2:49 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex41 min
Aug 4, 3:00 PM EDTSpecial Weather StatementBOXEssex45 min
Aug 4, 3:24 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Worcester48 min
Aug 4, 3:40 PM EDTSpecial Marine WarningBOX95 min
Aug 4, 3:46 PM EDTSpecial Marine WarningBOX59 min
Aug 4, 3:50 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex, Norfolk, Plymouth, Suffolk, Worcester55 min
Aug 4, 4:07 PM EDTAreal Flood WarningBOXEssex, Middlesex, Norfolk, Suffolk113 min
Aug 4, 4:11 PM EDTSpecial Marine WarningBOX64 min
Aug 4, 4:23 PM EDTSpecial Weather StatementBOXPlymouth37 min
Aug 4, 5:08 PM EDTSpecial Marine WarningBOX52 min
Aug 4, 5:18 PM EDTSpecial Weather StatementBOXWorcester42 min
Aug 4, 5:45 PM EDTSpecial Weather StatementBOXHampshire45 min
Aug 4, 6:17 PM EDTSpecial Weather StatementBOXNorfolk, Suffolk43 min
Aug 4, 7:30 PM EDTSpecial Weather StatementBOXSuffolk45 min

Nearby

Tornado Warnings in Massachusetts, 2015Every tornado warning in 2015Tornadoes in 2015

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.