Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 66, NWS Boston/Norton, MA

July 14, 2021Franklin County, Hampshire County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 14, 2021, 5:30 PM EDT for Franklin County, Hampshire County, Worcester County, Massachusetts. It was in force for 45 min. 11 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: Jul 14, 2021, 5:30 PM EDT (21:30 UTC)
Expired: Jul 14, 2021, 6:15 PM EDT
In force: 45 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Franklin County, MA, Hampshire County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 124 km from the middle of the area, began a volume at 21:32 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 14, 5:36 PM EDT	HAIL 0.88	Erving, MA	NICKEL SIZE HAIL
Jul 14, 5:40 PM EDT	HAIL 1	Erving, MA	QUARTER SIZE HAIL
Jul 14, 5:45 PM EDT	TSTM WND DMG	Erving, MA	TREE AND WIRES DOWN ON WELLS STREET AND STATE ROAD.
Jul 14, 5:45 PM EDT	TSTM WND DMG	Gill, MA	TREE DOWN ON MUNNS FERRY ROAD
Jul 14, 5:50 PM EDT	TSTM WND DMG	Wendell, MA	TREE AND LINES DOWN ON MONTAGUE ROAD AND MORMON HOLLOW ROAD
Jul 14, 5:55 PM EDT	TSTM WND DMG	Montague, MA	TREE AND WIRES DOWN ON EAST CHESTBUT HILL RD AT CHESTBUT HILL LOOP
Jul 14, 6:00 PM EDT	TSTM WND DMG	Leverett, MA	TREE AND WIRES DOWN ON LONG PLAIN ROAD
Jul 14, 6:22 PM EDT	HAIL 1.25	Amherst, MA	HALF DOLLAR SIZE HAIL
Jul 14, 6:24 PM EDT	TSTM WND DMG	Shutesbury, MA	TREE DOWN ON MONTAGUE RD
Jul 14, 6:25 PM EDT	TSTM WND DMG	Pelham, MA	TREE DOWN BLOCKING ROAD ON ENFIELD ROAD
Jul 14, 6:25 PM EDT	HAIL 0.75	Shutesbury, MA

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 9.5 hours before the alert went out and 114 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: 20 J/kg
Mixed-layer CIN: -211 J/kg
Mixed-layer LCL: 871 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 129 m²/s²
0-3 km storm-relative helicity: 134 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

645 
WUUS51 KBOX 142130
SVRBOX
MAC011-015-027-142215-
/O.NEW.KBOX.SV.W.0066.210714T2130Z-210714T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
530 PM EDT Wed Jul 14 2021

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  West central Worcester County in central Massachusetts...
  East central Hampshire County in western Massachusetts...
  Eastern Franklin County in western Massachusetts...

* Until 615 PM EDT.

* At 530 PM EDT, a severe thunderstorm was located over Montague, or
  near Greenfield, moving southeast at 15 mph.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Amherst, Greenfield, Orange, Deerfield, Belchertown, Athol, Ware,
  Montague, Barre, Hadley, Sunderland, Hatfield, Northfield,
  Hardwick, Bernardston, Conway, Leverett, Erving, Shutesbury and
  Phillipston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4246 7271 4269 7249 4252 7209 4226 7233
TIME...MOT...LOC 2130Z 308DEG 14KT 4258 7249 

HAIL...1.50IN
WIND...60MPH
 
$$

RM

1 follow-up statement

096 
WWUS51 KBOX 142154
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
554 PM EDT Wed Jul 14 2021

MAC011-015-027-142215-
/O.CON.KBOX.SV.W.0066.000000T0000Z-210714T2215Z/
Worcester MA-Hampshire MA-Franklin MA-
554 PM EDT Wed Jul 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR WEST CENTRAL WORCESTER...EAST CENTRAL HAMPSHIRE AND EASTERN
FRANKLIN COUNTIES...

At 553 PM EDT, a severe thunderstorm was located over Wendell, or 7
miles southwest of Orange, moving southeast at 15 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...
Amherst, Orange, Deerfield, Belchertown, Athol, Ware, Montague,
Hadley, Sunderland, Hatfield, Northfield, Hardwick, Leverett, Erving,
Shutesbury, Phillipston, Gill, Whately, Pelham and Petersham.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This storm is producing nickel size hail. SEEK SHELTER NOW inside a 
sturdy structure and stay away from windows.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 4244 7266 4266 7244 4255 7216 4253 7211
      4226 7234 4234 7249
TIME...MOT...LOC 2153Z 308DEG 14KT 4253 7240 

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

RM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 14, 12:32 AM EDT	Dense Fog Advisory	BOX	Barnstable, Bristol, Dukes, Essex, Middlesex, Nantucket and 4 more	9 hr
Jul 14, 3:36 AM EDT	Special Weather Statement	BOX	Hampden, Hampshire	39 min
Jul 14, 4:15 AM EDT	Special Weather Statement	BOX	Hampden, Hampshire	45 min
Jul 14, 4:46 PM EDT	Special Weather Statement	BOX	Worcester	44 min
Jul 14, 4:53 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Worcester	52 min
Jul 14, 6:05 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampden, Hampshire, Worcester	40 min
Jul 14, 6:38 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampden, Hampshire, Worcester	52 min
Jul 14, 7:16 PM EDT	Flash Flood Warning	BOX	Hampshire	53 min
Jul 14, 7:31 PM EDT	Special Weather Statement	BOX	Worcester	44 min
Jul 14, 7:33 PM EDT	Special Weather Statement	BOX	Hampden	42 min
Jul 14, 7:46 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampden, Hampshire, Worcester	26 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.