Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 33, NWS Boston/Norton, MA

June 30, 2021Essex County, Middlesex County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jun 30, 2021, 5:25 PM EDT for Essex County, Middlesex County, Massachusetts. It was in force for 49 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: Jun 30, 2021, 5:25 PM EDT (21:25 UTC)
Expired: Jun 30, 2021, 6:14 PM EDT
In force: 49 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Essex County, MA, Middlesex County, MA

The radar

The Boston radar (KBOX), 92 km from the middle of the area, began a volume at 21:27 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
Jun 30, 5:40 PM EDT	TSTM WND DMG	Haverhill, MA	TREE DOWN WITH POER POLE SNAPPED IN HALF. WIRES DOWN ON EAST BROADWAY

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
Jun 30, 3:21 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Gray, ME (KGYX), launched 12:00Z, 9.4 hours before the alert went out and 138 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: 906 J/kg
Mixed-layer CIN: -60 J/kg
Mixed-layer LCL: 1312 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 95 m²/s²
0-3 km storm-relative helicity: 102 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted.

507 
WUUS51 KBOX 302125
SVRBOX
MAC009-017-302230-
/O.NEW.KBOX.SV.W.0033.210630T2125Z-210630T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
525 PM EDT Wed Jun 30 2021

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Northwestern Essex County in northeastern Massachusetts...
  Northern Middlesex County in northeastern Massachusetts...

* Until 630 PM EDT.

* At 525 PM EDT, a severe thunderstorm was located near Haverhill,
  moving east at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect wind damage to trees and power lines. Minor hail 
           damage to vehicles is possible.

* Locations impacted include...
  Lowell, Lawrence, Haverhill, Methuen, Chelmsford, Andover, Dracut,
  North Andover, Westford, Newburyport, Amesbury, Ipswich,
  Tyngsborough, Salisbury, Georgetown, Boxford, Newbury, Groveland,
  Merrimac and Rowley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4287 7082 4283 7081 4281 7087 4280 7083
      4281 7081 4270 7078 4277 7082 4271 7083
      4270 7079 4264 7145 4270 7144 4270 7129
      4274 7124 4274 7118 4279 7118 4282 7114
      4281 7107 4286 7103 4289 7092
TIME...MOT...LOC 2125Z 277DEG 19KT 4282 7114 

HAIL...1.00IN
WIND...60MPH
 
$$

Frank

2 follow-up statements

938 
WWUS51 KBOX 302139
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
539 PM EDT Wed Jun 30 2021

MAC009-017-302230-
/O.CON.KBOX.SV.W.0033.000000T0000Z-210630T2230Z/
Essex MA-Middlesex MA-
539 PM EDT Wed Jun 30 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR NORTHWESTERN ESSEX AND NORTHERN MIDDLESEX COUNTIES...

At 538 PM EDT, a severe thunderstorm was located near Dracut, moving
east at 30 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to trees and power lines.

Locations impacted include...
Lowell, Lawrence, Haverhill, Methuen, Chelmsford, Andover, Dracut,
North Andover, Westford, Newburyport, Amesbury, Ipswich,
Tyngsborough, Salisbury, Georgetown, Boxford, Newbury, Groveland,
Merrimac and Rowley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4287 7082 4283 7081 4281 7087 4280 7083
      4281 7081 4270 7078 4277 7082 4271 7083
      4270 7079 4264 7145 4270 7144 4270 7129
      4274 7124 4274 7118 4279 7118 4282 7114
      4281 7107 4286 7103 4289 7092
TIME...MOT...LOC 2138Z 278DEG 25KT 4268 7123 

HAIL...0.75IN
WIND...60MPH
 
$$

Frank

200 
WWUS51 KBOX 302214
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
614 PM EDT Wed Jun 30 2021

MAC009-017-302224-
/O.CAN.KBOX.SV.W.0033.000000T0000Z-210630T2230Z/
Essex MA-Middlesex MA-
614 PM EDT Wed Jun 30 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN ESSEX AND
NORTHERN MIDDLESEX COUNTIES IS CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.  However heavy rain is
still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
northeastern Massachusetts.

LAT...LON 4287 7082 4283 7081 4281 7087 4280 7083
      4281 7081 4270 7078 4277 7082 4271 7083
      4270 7079 4264 7145 4270 7144 4270 7129
      4274 7124 4274 7118 4279 7118 4282 7114
      4281 7107 4286 7103 4289 7092
TIME...MOT...LOC 2212Z 277DEG 19KT 4266 7097 

$$

Frank

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 2:29 AM EDT	Small Craft Advisory	BOX		18 hr
Jun 30, 3:40 PM EDT	Special Weather Statement	BOX	Hampshire	65 min
Jun 30, 3:42 PM EDT	Special Weather Statement	BOX	Franklin	63 min
Jun 30, 3:48 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampden, Hampshire	57 min
Jun 30, 4:03 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire	57 min
Jun 30, 4:32 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Middlesex, Worcester	58 min
Jun 30, 4:39 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampden, Hampshire, Worcester	66 min
Jun 30, 4:45 PM EDT	Tornado Warning	BOX	Franklin, Worcester	26 min
Jun 30, 5:00 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Worcester	30 min
Jun 30, 5:13 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Worcester	62 min
Jun 30, 5:26 PM EDT	Special Marine Warning	BOX		64 min
Jun 30, 5:29 PM EDT	Severe Thunderstorm Warning	BOX	Worcester	44 min
Jun 30, 5:43 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex	51 min
Jun 30, 5:54 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Norfolk, Suffolk, Worcester	53 min
Jun 30, 5:58 PM EDT	Special Marine Warning	BOX		62 min
Jun 30, 6:11 PM EDT	Special Weather Statement	BOX	Norfolk	49 min
Jun 30, 6:12 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Norfolk, Plymouth, Suffolk, Worcester	47 min
Jun 30, 6:22 PM EDT	Special Marine Warning	BOX		53 min
Jun 30, 6:31 PM EDT	Special Marine Warning	BOX		59 min
Jun 30, 6:45 PM EDT	Severe Thunderstorm Warning	BOX	Hampden	60 min
Jun 30, 6:57 PM EDT	Special Marine Warning	BOX		33 min
Jun 30, 7:15 PM EDT	Severe Thunderstorm Warning	BOX	Hampden, Worcester	60 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2021 Every severe thunderstorm warning in 2021

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.