Alert archive / Massachusetts / Tornado Warnings in 2018

Tornado Warning 10, NWS Boston/Norton, MA

August 4, 2018Middlesex County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this tornado warning at Aug 4, 2018, 10:07 AM EDT for Middlesex County, Worcester County, Massachusetts. It was in force for 38 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: Aug 4, 2018, 10:07 AM EDT (14:07 UTC)
Expired: Aug 4, 2018, 10:45 AM EDT
In force: 38 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

Counties Middlesex County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 53 km from the middle of the area, began a volume at 14:11 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, 10:36 AM EDT	TSTM WND DMG	Grafton, MA	LARGE BRANCHES DOWN AND SIDING OF BUILDING BLOWN OFF IN GREEN ACRES ESTATES IN SOUTH GRAFTON.

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, 2.1 hours before the alert went out and 155 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: 273 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 770 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 12 m²/s²
0-3 km storm-relative helicity: 37 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

950 
WFUS51 KBOX 041407
TORBOX
MAC017-027-041445-
/O.NEW.KBOX.TO.W.0010.180804T1407Z-180804T1445Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Boston/Norton MA
1007 AM EDT SAT AUG 4 2018

The National Weather Service in Boston/Norton has issued a

* Tornado Warning for...
  Southeastern Worcester County in central Massachusetts...
  South central Middlesex County in northeastern Massachusetts...

* Until 1045 AM EDT.
    
* At 1006 AM EDT, a severe thunderstorm capable of producing a
  tornado was located near Oxford, or 11 miles south of Worcester, 
  moving northeast at 30 mph. There have been several reports of 
  damage but a tornado has not been confirmed. GET TO SAFE SHELTER 
  NOW!!!

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Northbridge, Millbury and Sutton around 1025 AM EDT.
  Grafton and Upton around 1035 AM EDT.
  Shrewsbury around 1040 AM EDT.
  Marlborough, Westborough, Ashland, Hopkinton, Northborough and 
  Southborough around 1045 AM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4205 7182 4210 7189 4238 7162 4224 7143
TIME...MOT...LOC 1406Z 226DEG 25KT 4210 7182 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

JWD

4 follow-up statements

090 
WWUS51 KBOX 041416
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1016 AM EDT SAT AUG 4 2018

MAC017-027-041445-
/O.CON.KBOX.TO.W.0010.000000T0000Z-180804T1445Z/
Worcester MA-Middlesex MA-
1016 AM EDT SAT AUG 4 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1045 AM EDT FOR
SOUTHEASTERN WORCESTER AND SOUTH CENTRAL MIDDLESEX COUNTIES...
    
At 1015 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Sutton, or 8 miles south of Worcester, moving 
northeast at 30 mph. There have been numerous reports of significant 
damage in Dudley and Webster.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Northbridge around 1025 AM EDT.
  Grafton around 1030 AM EDT.
  Upton around 1035 AM EDT.
  Shrewsbury around 1040 AM EDT.
  Marlborough, Westborough, Ashland, Hopkinton, Northborough, 
  Southborough and Berlin around 1045 AM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4209 7175 4214 7182 4238 7162 4224 7143
TIME...MOT...LOC 1415Z 226DEG 25KT 4215 7176 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

JWD

535 
WWUS51 KBOX 041425
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1025 AM EDT SAT AUG 4 2018

MAC017-027-041445-
/O.CON.KBOX.TO.W.0010.000000T0000Z-180804T1445Z/
Worcester MA-Middlesex MA-
1025 AM EDT SAT AUG 4 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1045 AM EDT FOR
SOUTHEASTERN WORCESTER AND SOUTH CENTRAL MIDDLESEX COUNTIES...
    
At 1024 AM EDT, a severe thunderstorm capable of producing a tornado 
was located over Grafton moving northeast at 30 mph. There have been 
many reports of significant damage in Webster. GET TO SAFETY 
IMMEDIATELY!

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Upton around 1035 AM EDT.
  Shrewsbury around 1040 AM EDT.
  Westborough, Hopkinton and Northborough around 1045 AM EDT.
  Berlin around 1050 AM EDT.
  Marlborough, Ashland and Southborough around 1055 AM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4215 7168 4219 7175 4236 7162 4225 7146
TIME...MOT...LOC 1424Z 226DEG 25KT 4219 7170 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

JWD

689 
WWUS51 KBOX 041437
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1037 AM EDT SAT AUG 4 2018

MAC017-027-041445-
/O.CON.KBOX.TO.W.0010.000000T0000Z-180804T1445Z/
Worcester MA-Middlesex MA-
1037 AM EDT SAT AUG 4 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1045 AM EDT FOR EAST
CENTRAL WORCESTER AND SOUTH CENTRAL MIDDLESEX COUNTIES...
    
At 1036 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Grafton, moving northeast at 20 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Westborough, Hopkinton, Northborough and Southborough around 1045 
  AM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4221 7163 4224 7170 4236 7162 4225 7146
TIME...MOT...LOC 1436Z 224DEG 20KT 4223 7165 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

JWD

569 
WWUS51 KBOX 041441
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1041 AM EDT SAT AUG 4 2018

MAC017-027-041449-
/O.EXP.KBOX.TO.W.0010.000000T0000Z-180804T1445Z/
Worcester MA-Middlesex MA-
1041 AM EDT SAT AUG 4 2018

...THE TORNADO WARNING FOR EAST CENTRAL WORCESTER AND SOUTH CENTRAL
MIDDLESEX COUNTIES WILL EXPIRE AT 1045 AM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.

There have been many reports of significant damage in Webster and 
Dudley. Stay away from downed wires and obey posted road closures.

A survey team from the National Weather Service is en route 
to investigate the damage.

&&

LAT...LON 4221 7163 4224 7170 4236 7162 4225 7146
TIME...MOT...LOC 1439Z 226DEG 25KT 4223 7165 

$$

JWD

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 4, 5:56 AM EDT	Special Weather Statement	BOX	Franklin, Hampden, Hampshire	49 min
Aug 4, 7:02 AM EDT	Areal Flood Advisory	BOX	Hampden, Hampshire	58 min
Aug 4, 7:53 AM EDT	Areal Flood Advisory	BOX	Hampden	3 hr
Aug 4, 8:48 AM EDT	Areal Flood Advisory	BOX	Hampden, Hampshire, Worcester	3 hr
Aug 4, 9:31 AM EDT	Severe Thunderstorm Warning	BOX	Worcester	44 min
Aug 4, 9:35 AM EDT	Tornado Warning	BOX	Worcester	25 min
Aug 4, 9:57 AM EDT	Tornado Warning	BOX	Worcester	32 min
Aug 4, 10:00 AM EDT	Areal Flood Advisory	BOX	Bristol, Middlesex, Norfolk, Worcester	2 hr
Aug 4, 10:24 AM EDT	Flash Flood Warning	BOX	Middlesex, Norfolk, Worcester	106 min
Aug 4, 10:54 AM EDT	Areal Flood Advisory	BOX	Bristol, Essex, Middlesex, Norfolk, Suffolk	2 hr
Aug 4, 11:14 AM EDT	Areal Flood Advisory	BOX	Barnstable, Bristol, Norfolk, Plymouth	3 hr
Aug 4, 11:23 AM EDT	Flash Flood Warning	BOX	Essex, Middlesex, Norfolk, Suffolk	93 min
Aug 4, 11:31 AM EDT	Flash Flood Warning	BOX	Bristol	3 hr
Aug 4, 11:43 AM EDT	Special Weather Statement	BOX	Suffolk	47 min
Aug 4, 11:46 AM EDT	Special Marine Warning	BOX		119 min
Aug 4, 12:08 PM EDT	Flash Flood Warning	BOX	Bristol, Plymouth	3 hr
Aug 4, 1:46 PM EDT	Special Marine Warning	BOX		44 min
Aug 4, 1:47 PM EDT	Special Marine Warning	BOX		43 min
Aug 4, 2:17 PM EDT	Flash Flood Warning	BOX	Bristol, Plymouth	113 min
Aug 4, 2:42 PM EDT	Flash Flood Warning	BOX	Bristol, Plymouth	45 min
Aug 4, 4:10 PM EDT	Special Marine Warning	BOX		35 min
Aug 4, 4:26 PM EDT	Special Weather Statement	BOX	Dukes	34 min
Aug 4, 4:30 PM EDT	Severe Thunderstorm Warning	BOX	Barnstable, Dukes	45 min
Aug 4, 4:40 PM EDT	Special Marine Warning	BOX		35 min
Aug 4, 5:14 PM EDT	Special Marine Warning	BOX		15 min
Aug 4, 5:18 PM EDT	Special Weather Statement	BOX	Barnstable	42 min
Aug 4, 5:23 PM EDT	Areal Flood Advisory	BOX	Barnstable	2 hr
Aug 4, 5:36 PM EDT	Special Weather Statement	BOX	Middlesex	39 min
Aug 4, 6:09 PM EDT	Special Weather Statement	BOX	Worcester	51 min
Aug 4, 6:36 PM EDT	Special Weather Statement	BOX	Hampden	39 min
Aug 4, 6:58 PM EDT	Special Weather Statement	BOX	Worcester	47 min

Nearby

Tornado Warnings in Massachusetts, 2018 Every tornado warning in 2018 Tornadoes in 2018

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.