Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 39, NWS Boston/Norton, MA

July 18, 2016Middlesex County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 18, 2016, 2:56 PM EDT for Middlesex County, Worcester County, Massachusetts. It was in force for 34 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: Jul 18, 2016, 2:56 PM EDT (18:56 UTC)
Expired: Jul 18, 2016, 3:30 PM EDT
In force: 34 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Middlesex County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 92 km from the middle of the area, began a volume at 18:58 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
Jul 18, 3:00 PM EDT	TSTM WND DMG	Ashburnham, MA	TREE DOWN ON EAST RINGE ROAD. 2 LARGE BRANCHES DOWN ON PENACOOK DRIVE AT SUNSET LAKE.

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
Jul 18, 12:05 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Gray, ME (KGYX), launched 12:00Z, 6.9 hours before the alert went out and 181 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: 24 J/kg
Mixed-layer CIN: -141 J/kg
Mixed-layer LCL: 1173 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 216 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

999 
WUUS51 KBOX 181856
SVRBOX
MAC017-027-181930-
/O.NEW.KBOX.SV.W.0039.160718T1856Z-160718T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
256 PM EDT MON JUL 18 2016

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  NORTHWESTERN MIDDLESEX COUNTY IN NORTHEASTERN MASSACHUSETTS...

* UNTIL 330 PM EDT

* AT 256 PM EDT...A SEVERE THUNDERSTORM WAS LOCATED OVER
  ASHBURNHAM... OR NEAR FITCHBURG...MOVING EAST AT 50 MPH.
  THIS STORM HAS A HISTORY OF DOWNING TREES IN ORANGE AND
  ATHOL AS WELL AS THROUGHOUT FRANKLIN COUNTY.

  HAZARD...60 MPH WIND GUSTS. 

  SOURCE...RADAR INDICATED. 

  IMPACT...EXPECT DAMAGE TO ROOFS...SIDING...AND TREES. 

* LOCATIONS IMPACTED INCLUDE...
  FITCHBURG...GARDNER...PEPPERELL...GROTON...WINCHENDON...
  LUNENBURG...TOWNSEND...WESTMINSTER...SHIRLEY...ASHBURNHAM...
  RINDGE...NEW IPSWICH...DUNSTABLE...ASHBY AND MASON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 4270 7151 4260 7151 4257 7201 4272 7206
TIME...MOT...LOC 1856Z 257DEG 43KT 4265 7194 

HAIL...<.75IN
WIND...60MPH
 
$$
FIELD

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 1:22 PM EDT	Special Weather Statement	BOX	Franklin	38 min
Jul 18, 1:42 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire	48 min
Jul 18, 2:18 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Worcester	27 min
Jul 18, 2:30 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Worcester	45 min
Jul 18, 3:08 PM EDT	Special Weather Statement	BOX	Essex	37 min
Jul 18, 3:17 PM EDT	Severe Thunderstorm Warning	BOX	Essex	28 min
Jul 18, 3:31 PM EDT	Special Weather Statement	BOX	Middlesex	29 min
Jul 18, 3:53 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Norfolk, Suffolk	52 min
Jul 18, 4:08 PM EDT	Special Marine Warning	BOX		52 min
Jul 18, 4:14 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Norfolk, Suffolk	46 min
Jul 18, 4:31 PM EDT	Special Marine Warning	BOX		59 min
Jul 18, 4:34 PM EDT	Severe Thunderstorm Warning	BOX	Norfolk, Plymouth, Suffolk	41 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2016 Every severe thunderstorm warning in 2016

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.