Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 13, NWS Boston/Norton, MA

June 27, 2023Middlesex County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jun 27, 2023, 3:13 AM EDT for Middlesex County, Worcester County, Massachusetts. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 27, 2023, 3:13 AM EDT (07:13 UTC)
Expired
Jun 27, 2023, 3:37 AM EDT
In force
24 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), 84 km from the middle of the area, began a volume at 07:15 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.

The nearest sounding before it

Gray, ME (KGYX), launched 00:00Z, 7.2 hours before the alert went out and 183 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, Gray, ME at 00:00Z on 2023-06-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 21 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Gray, ME at 00:00Z on 2023-06-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 105 square meters per square second.1939Sfc1 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
21 J/kg
Mixed-layer CIN
-96 J/kg
Mixed-layer LCL
453 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
105 m²/s²
0-3 km storm-relative helicity
119 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

240 
WUUS51 KBOX 270713
SVRBOX
MAC017-027-270800-
/O.NEW.KBOX.SV.W.0013.230627T0713Z-230627T0800Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
313 AM EDT Tue Jun 27 2023

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Northeastern Worcester County in central Massachusetts...
  Northwestern Middlesex County in northeastern Massachusetts...

* Until 400 AM EDT.

* At 313 AM EDT, a severe thunderstorm was located over Leominster,
  moving northeast at 35 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Leominster, Fitchburg, Dracut, Westford, Gardner, Pepperell,
  Tyngsborough, Groton, Lunenburg, Townsend, Lancaster, Sterling,
  Ayer, Westminster, Shirley, Harvard, Ashburnham, Hubbardston,
  Princeton and Dunstable.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4269 7135 4245 7178 4249 7203 4271 7182
TIME...MOT...LOC 0713Z 211DEG 30KT 4252 7176 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BL
2 follow-up statements
983 
WWUS51 KBOX 270731
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
331 AM EDT Tue Jun 27 2023

MAC017-027-270800-
/O.CON.KBOX.SV.W.0013.000000T0000Z-230627T0800Z/
Worcester MA-Middlesex MA-
331 AM EDT Tue Jun 27 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 AM EDT
FOR NORTH CENTRAL WORCESTER AND NORTHWESTERN MIDDLESEX COUNTIES...

At 331 AM EDT, a severe thunderstorm was located over Pepperell, or 9
miles northeast of Fitchburg, moving northeast at 35 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Fitchburg, Dracut, Westford, Pepperell, Tyngsborough, Groton,
Lunenburg, Townsend, Ayer, Shirley, Ashburnham, Dunstable and Ashby.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4269 7135 4258 7155 4258 7171 4265 7188
      4271 7182
TIME...MOT...LOC 0731Z 211DEG 30KT 4265 7165 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BL
882 
WWUS51 KBOX 270737
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
337 AM EDT Tue Jun 27 2023

MAC017-027-270747-
/O.CAN.KBOX.SV.W.0013.000000T0000Z-230627T0800Z/
Worcester MA-Middlesex MA-
337 AM EDT Tue Jun 27 2023

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WORCESTER AND
NORTHWESTERN MIDDLESEX COUNTIES IS CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.

LAT...LON 4269 7135 4258 7155 4258 7171 4265 7188
      4271 7182
TIME...MOT...LOC 0736Z 211DEG 30KT 4270 7161 

$$

BL

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 26, 8:49 PM EDTSpecial Weather StatementBOXFranklin, Hampshire56 min
Jun 26, 9:50 PM EDTSpecial Weather StatementBOXFranklin55 min
Jun 27, 1:20 AM EDTSpecial Marine WarningBOX25 min
Jun 27, 1:40 AM EDTSevere Thunderstorm WarningBOXWorcester50 min
Jun 27, 2:00 AM EDTSpecial Marine WarningBOX19 min
Jun 27, 2:25 AM EDTSpecial Marine WarningBOX65 min
Jun 27, 2:31 AM EDTSpecial Weather StatementBOXWorcester44 min
Jun 27, 3:28 AM EDTSpecial Marine WarningBOX46 min
Jun 27, 4:29 AM EDTSpecial Weather StatementBOXNantucket31 min
Jun 27, 4:33 AM EDTSpecial Weather StatementBOXBristol42 min
Jun 27, 4:44 AM EDTFlash Flood WarningBOXBristol56 min
Jun 27, 6:14 AM EDTSpecial Marine WarningBOX61 min
Jun 27, 7:08 AM EDTSpecial Marine WarningBOX52 min
Jun 27, 9:52 AM EDTSpecial Marine WarningBOX53 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2023Every severe thunderstorm warning in 2023

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.