Alert archive / Massachusetts / Tornado Warnings in 2015

Tornado Warning 8, NWS Boston/Norton, MA

August 4, 2015Middlesex County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this tornado warning at Aug 4, 2015, 2:07 PM EDT for Middlesex County, Worcester County, Massachusetts. It was in force for 23 min. 9 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, 2:07 PM EDT (18:07 UTC)
Expired: Aug 4, 2015, 2:30 PM EDT
In force: 23 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon

Counties Middlesex County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 73 km from the middle of the area, began a volume at 18:07 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
Aug 4, 2:09 PM EDT	HAIL 1	Leominster, MA
Aug 4, 2:25 PM EDT	HAIL 1	Shirley, MA
Aug 4, 2:25 PM EDT	HAIL 1	Shirley, MA	FORT DEVENS AREA
Aug 4, 2:34 PM EDT	HAIL 1	Acton, MA
Aug 4, 2:35 PM EDT	HAIL 2	Littleton, MA
Aug 4, 2:37 PM EDT	HAIL 1	Westford, MA
Aug 4, 2:39 PM EDT	TSTM WND DMG	Boxboro, MA	TREES AND WIRES DOWN ON MASSACHUSETTS AVENUE NEAR STOW AND BURROUGHS ROADS
Aug 4, 2:40 PM EDT	TSTM WND DMG	Littleton, MA	TREE DOWN DAHLIA DRIVE
Aug 4, 2:40 PM EDT	TSTM WND DMG	Littleton, MA	TREE DOWN ON DAHLIA DRIVE

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.

Issued	Product	Office	Lasted
Aug 4, 12:18 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Chatham, MA (KCHH), launched 12:00Z, 6.1 hours before the alert went out and 164 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: 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.

088 
WFUS51 KBOX 041807
TORBOX
MAC017-027-041830-
/O.NEW.KBOX.TO.W.0008.150804T1807Z-150804T1830Z/

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

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

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

* UNTIL 230 PM EDT
    
* AT 206 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED
  OVER LEOMINSTER...AND WAS MOVING EAST AT 35 MPH.

* SOME LOCATIONS IMPACTED INCLUDE...
  LOWELL...LEOMINSTER...FITCHBURG...BILLERICA...CHELMSFORD...
  WESTFORD...ACTON...CONCORD...CLINTON...BEDFORD...TYNGSBOROUGH...
  GROTON...LUNENBURG...LITTLETON...LANCASTER...STERLING...AYER...
  SHIRLEY...STOW AND HARVARD.

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 4242 7177 4254 7183 4269 7140 4249 7127
TIME...MOT...LOC 1806Z 253DEG 42KT 4250 7173 
$$

KJC

1 follow-up statement

356 
WWUS51 KBOX 041820
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
220 PM EDT TUE AUG 4 2015

MAC017-027-041830-
/O.CON.KBOX.TO.W.0008.000000T0000Z-150804T1830Z/
WORCESTER MA-MIDDLESEX MA-
220 PM EDT TUE AUG 4 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 230 PM EDT FOR EAST
CENTRAL WORCESTER AND NORTH CENTRAL MIDDLESEX COUNTIES...
    
AT 220 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE
OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED OVER
LITTLETON...OR 7 MILES SOUTHWEST OF CHELMSFORD...MOVING EAST AT 50
MPH.

LOCATIONS IMPACTED INCLUDE...
LOWELL...BILLERICA...CHELMSFORD...WESTFORD...ACTON...CONCORD...
BEDFORD...TYNGSBOROUGH...GROTON...LUNENBURG...LITTLETON...
LANCASTER...AYER...SHIRLEY...STOW...HARVARD...BOXBOROUGH...BOLTON...
CARLISLE AND DUNSTABLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! LEAVE MOBILE HOMES AND GO TO A STRONG BUILDING. GO TO
THE BASEMENT OR AN INTERIOR ROOM ON THE LOWEST FLOOR. STAY AWAY FROM
WINDOWS.

&&

LAT...LON 4244 7166 4255 7169 4269 7140 4249 7127
TIME...MOT...LOC 1820Z 253DEG 42KT 4255 7151 

$$

KJC

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 4, 4:11 AM EDT	Special Weather Statement	BOX	Franklin, Hampshire	64 min
Aug 4, 6:09 AM EDT	Severe Thunderstorm Warning	BOX	Bristol, Norfolk, Plymouth	66 min
Aug 4, 6:13 AM EDT	Special Marine Warning	BOX		62 min
Aug 4, 6:53 AM EDT	Severe Thunderstorm Warning	BOX	Barnstable, Bristol, Norfolk, Plymouth	52 min
Aug 4, 6:54 AM EDT	Severe Thunderstorm Warning	BOX	Bristol, Plymouth	51 min
Aug 4, 6:55 AM EDT	Special Marine Warning	BOX		65 min
Aug 4, 7:01 AM EDT	Special Marine Warning	BOX		89 min
Aug 4, 7:15 AM EDT	Severe Thunderstorm Warning	BOX	Barnstable	60 min
Aug 4, 7:48 AM EDT	Special Weather Statement	BOX	Essex	42 min
Aug 4, 7:54 AM EDT	Special Marine Warning	BOX		66 min
Aug 4, 8:06 AM EDT	Severe Thunderstorm Warning	BOX	Essex	24 min
Aug 4, 8:15 AM EDT	Special Marine Warning	BOX		60 min
Aug 4, 12:32 PM EDT	Special Weather Statement	BOX	Franklin	43 min
Aug 4, 12:41 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire, Worcester	64 min
Aug 4, 1:21 PM EDT	Special Weather Statement	BOX	Hampshire	54 min
Aug 4, 1:28 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire	47 min
Aug 4, 1:35 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Worcester	40 min
Aug 4, 1:57 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire	63 min
Aug 4, 2:05 PM EDT	Special Weather Statement	BOX	Hampden, Hampshire	40 min
Aug 4, 2:17 PM EDT	Severe Thunderstorm Warning	BOX	Hampden, Hampshire, Worcester	58 min
Aug 4, 2:25 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire, Worcester	65 min
Aug 4, 2:28 PM EDT	Tornado Warning	BOX	Middlesex	32 min
Aug 4, 2:39 PM EDT	Tornado Warning	BOX	Franklin, Worcester	46 min
Aug 4, 2:47 PM EDT	Special Marine Warning	BOX		58 min
Aug 4, 2:49 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex	41 min
Aug 4, 3:00 PM EDT	Special Weather Statement	BOX	Essex	45 min
Aug 4, 3:24 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Worcester	48 min
Aug 4, 3:40 PM EDT	Special Marine Warning	BOX		95 min
Aug 4, 3:46 PM EDT	Special Marine Warning	BOX		59 min
Aug 4, 3:50 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex, Norfolk, Plymouth, Suffolk, Worcester	55 min
Aug 4, 4:07 PM EDT	Areal Flood Warning	BOX	Essex, Middlesex, Norfolk, Suffolk	113 min
Aug 4, 4:11 PM EDT	Special Marine Warning	BOX		64 min
Aug 4, 4:23 PM EDT	Special Weather Statement	BOX	Plymouth	37 min
Aug 4, 5:08 PM EDT	Special Marine Warning	BOX		52 min
Aug 4, 5:18 PM EDT	Special Weather Statement	BOX	Worcester	42 min
Aug 4, 5:45 PM EDT	Special Weather Statement	BOX	Hampshire	45 min
Aug 4, 6:17 PM EDT	Special Weather Statement	BOX	Norfolk, Suffolk	43 min
Aug 4, 7:30 PM EDT	Special Weather Statement	BOX	Suffolk	45 min

Nearby

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