Alert archive / Massachusetts / Tornado Warnings in 2018

Tornado Warning 9, NWS Boston/Norton, MA

August 4, 2018Worcester County, Massachusetts

NWS Boston/Norton, MA issued this tornado warning at Aug 4, 2018, 9:57 AM EDT for Worcester County, Massachusetts. It was in force for 32 min. 2 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, 2018, 9:57 AM EDT (13:57 UTC)
Expired
Aug 4, 2018, 10:29 AM EDT
In force
32 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.0 in

County Worcester County, MA

The radar

The Boston radar (KBOX), 54 km from the middle of the area, began a volume at 13:59 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, 10:00 AM EDTTSTM WND DMGWebster, MADOWNED TREE LIMBS AND UTILITY POLES ON MAIN STREET NEAR RAILROAD CROSSING.
Aug 4, 10:05 AM EDTTSTM WND DMGWebster, MAMAIN STREET...CHASE AVENUE...AND PLEASANT STREET...MANY TREES AND POWER LINES DOWN. PARTIAL BUILDING COLLAPSE TO METRO PCS ON MAIN STREET. SEVERAL OTHER STRUCTURES ON MAIN STREET WITH ROOF DAMAGE.

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, 2.0 hours before the alert went out and 156 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 2018-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 273 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Chatham, MA at 12:00Z on 2018-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 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
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.

283 
WFUS51 KBOX 041357
TORBOX
MAC027-041445-
/O.NEW.KBOX.TO.W.0009.180804T1357Z-180804T1445Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Boston/Norton MA
957 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...

* Until 1045 AM EDT.
    
* At 956 AM EDT, a severe thunderstorm capable of producing a tornado
  was located over Webster, or 15 miles south of Worcester, moving 
  northeast at 25 mph. Trees have been downed in portions of 
  Woodstock Connecticut but a tornado has not been confirmed.

  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...
  Webster around 1005 AM EDT.
  Oxford around 1010 AM EDT.
  Douglas around 1015 AM EDT.
  Sutton around 1025 AM EDT.
  Northbridge and Uxbridge around 1035 AM EDT.
  Upton around 1040 AM EDT.
  Blackstone and Mendon 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 4203 7190 4206 7191 4220 7159 4206 7154
TIME...MOT...LOC 1356Z 247DEG 21KT 4205 7188 

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

$$

JWD
1 follow-up statement
806 
WWUS51 KBOX 041429
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1029 AM EDT SAT AUG 4 2018

MAC027-041439-
/O.CAN.KBOX.TO.W.0009.000000T0000Z-180804T1445Z/
Worcester MA-
1029 AM EDT SAT AUG 4 2018

...THE TORNADO WARNING FOR SOUTHEASTERN WORCESTER COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.

&&

LAT...LON 4203 7190 4206 7191 4220 7159 4206 7154
TIME...MOT...LOC 1428Z 247DEG 21KT 4213 7164 

$$

JWD

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 5:56 AM EDTSpecial Weather StatementBOXFranklin, Hampden, Hampshire49 min
Aug 4, 7:02 AM EDTAreal Flood AdvisoryBOXHampden, Hampshire58 min
Aug 4, 7:53 AM EDTAreal Flood AdvisoryBOXHampden3 hr
Aug 4, 8:48 AM EDTAreal Flood AdvisoryBOXHampden, Hampshire, Worcester3 hr
Aug 4, 9:31 AM EDTSevere Thunderstorm WarningBOXWorcester44 min
Aug 4, 9:35 AM EDTTornado WarningBOXWorcester25 min
Aug 4, 10:00 AM EDTAreal Flood AdvisoryBOXBristol, Middlesex, Norfolk, Worcester2 hr
Aug 4, 10:07 AM EDTTornado WarningBOXMiddlesex, Worcester38 min
Aug 4, 10:24 AM EDTFlash Flood WarningBOXMiddlesex, Norfolk, Worcester106 min
Aug 4, 10:54 AM EDTAreal Flood AdvisoryBOXBristol, Essex, Middlesex, Norfolk, Suffolk2 hr
Aug 4, 11:14 AM EDTAreal Flood AdvisoryBOXBarnstable, Bristol, Norfolk, Plymouth3 hr
Aug 4, 11:23 AM EDTFlash Flood WarningBOXEssex, Middlesex, Norfolk, Suffolk93 min
Aug 4, 11:31 AM EDTFlash Flood WarningBOXBristol3 hr
Aug 4, 11:43 AM EDTSpecial Weather StatementBOXSuffolk47 min
Aug 4, 11:46 AM EDTSpecial Marine WarningBOX119 min
Aug 4, 12:08 PM EDTFlash Flood WarningBOXBristol, Plymouth3 hr
Aug 4, 1:46 PM EDTSpecial Marine WarningBOX44 min
Aug 4, 1:47 PM EDTSpecial Marine WarningBOX43 min
Aug 4, 2:17 PM EDTFlash Flood WarningBOXBristol, Plymouth113 min
Aug 4, 2:42 PM EDTFlash Flood WarningBOXBristol, Plymouth45 min
Aug 4, 4:10 PM EDTSpecial Marine WarningBOX35 min
Aug 4, 4:26 PM EDTSpecial Weather StatementBOXDukes34 min
Aug 4, 4:30 PM EDTSevere Thunderstorm WarningBOXBarnstable, Dukes45 min
Aug 4, 4:40 PM EDTSpecial Marine WarningBOX35 min
Aug 4, 5:14 PM EDTSpecial Marine WarningBOX15 min
Aug 4, 5:18 PM EDTSpecial Weather StatementBOXBarnstable42 min
Aug 4, 5:23 PM EDTAreal Flood AdvisoryBOXBarnstable2 hr
Aug 4, 5:36 PM EDTSpecial Weather StatementBOXMiddlesex39 min
Aug 4, 6:09 PM EDTSpecial Weather StatementBOXWorcester51 min
Aug 4, 6:36 PM EDTSpecial Weather StatementBOXHampden39 min
Aug 4, 6:58 PM EDTSpecial Weather StatementBOXWorcester47 min

Nearby

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