Severe thunderstorms swept across western, central, and northeast Massachusetts and caused widespread damage. There were many reports of downed trees, large limbs, and power lines from winds estimated to have gusted as high as 60 mph from the east slopes of the Berkshires across Worcester  County to the Merrimack Valley. In Worcester County, a downburst cut a path of damage over a four mile stretch, from Ball Hill in the northwest corner of Northborough to a little to the southeast of the Algonquin High School parking lot. A number of pine trees from 1 to 2 feet in diameter were snapped off at various heights.The storms also produced large and damaging hail. A pilot at Tewksbury Airport reported two inch diameter hail which lasted four minutes. It caused damage to several parked aircraft. Golf ball sized hail was reported by amateur radio operators in Ashburnham and Townsend. Several cars sustained damage from the hail in Townsend. Lightning from the storms ignited a fire which caused extensive damage to several houses in Tewksbury. One person was struck by lightning at a campground on Peppermint Hill in Cummington.

Hail in WORCESTER, MASSACHUSETTS
From 20-AUG-04 17:05:00 to 20-AUG-04 17:25:00 (EST)
Location: NORTHBOROUGH
Magnitude: 1.25 
Property damage: 25K
Reported by: TRAINED SPOTTER

Hail in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 17:15:00 to 20-AUG-04 17:37:00 (EST)
Location: MARLBOROUGH
Magnitude: 0.88 
Reported by: AMATEUR RADIO

Hail in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 14:25:00 to 20-AUG-04 14:25:00 (EST)
Location: LOWELL
Magnitude: 0.75 
Reported by: AMATEUR RADIO

Thunderstorm Wind in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 13:58:00 to 20-AUG-04 13:58:00 (EST)
Location: TOWNSEND
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Thunderstorm Wind in ESSEX, MASSACHUSETTS
From 20-AUG-04 16:15:00 to 20-AUG-04 16:15:00 (EST)
Location: BEVERLY
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Thunderstorm Wind in WORCESTER, MASSACHUSETTS
From 20-AUG-04 17:04:00 to 20-AUG-04 17:10:00 (EST)
Location: WEST BOYLSTON
Magnitude: 60 EG
Property damage: 150K
Reported by: NWS STORM SURVEY

Hail in WORCESTER, MASSACHUSETTS
From 20-AUG-04 13:25:00 to 20-AUG-04 13:50:00 (EST)
Location: ASHBURNHAM
Magnitude: 1.75 
Property damage: 10K
Reported by: AMATEUR RADIO

Hail in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 13:55:00 to 20-AUG-04 13:55:00 (EST)
Location: TOWNSEND
Magnitude: 1.75 
Property damage: 25K
Reported by: AMATEUR RADIO

Hail in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 15:33:00 to 20-AUG-04 15:45:00 (EST)
Location: TEWKSBURY
Magnitude: 2.00 
Property damage: 50K
Reported by: AMATEUR RADIO

Thunderstorm Wind in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 14:25:00 to 20-AUG-04 14:25:00 (EST)
Location: CHELMSFORD CENTER
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Hail in ESSEX, MASSACHUSETTS
From 20-AUG-04 14:45:00 to 20-AUG-04 14:45:00 (EST)
Location: ANDOVER
Magnitude: 0.75 
Reported by: AMATEUR RADIO

Funnel Cloud in WORCESTER, MASSACHUSETTS
From 20-AUG-04 13:13:00 to 20-AUG-04 13:13:00 (EST)
Location: GARDNER
Reported by: AMATEUR RADIO

Thunderstorm Wind in FRANKLIN, MASSACHUSETTS
From 20-AUG-04 15:30:00 to 20-AUG-04 15:30:00 (EST)
Location: LEVERETT
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Lightning in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 15:30:00 to 20-AUG-04 15:30:00 (EST)
Location: TEWKSBURY
Property damage: 50K
Reported by: AMATEUR RADIO

Thunderstorm Wind in HAMPSHIRE, MASSACHUSETTS
From 20-AUG-04 15:35:00 to 20-AUG-04 15:40:00 (EST)
Location: CHESTERFIELD
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Thunderstorm Wind in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 17:40:00 to 20-AUG-04 18:17:00 (EST)
Location: SUDBURY
Magnitude: 50 EG
Property damage: 75K
Reported by: AMATEUR RADIO

Lightning in HAMPSHIRE, MASSACHUSETTS
From 20-AUG-04 18:45:00 to 20-AUG-04 18:45:00 (EST)
Location: CUMMINGTON
Reported by: AMATEUR RADIO

Thunderstorm Wind in WORCESTER, MASSACHUSETTS
From 20-AUG-04 13:20:00 to 20-AUG-04 13:55:00 (EST)
Location: WINCHENDON
Magnitude: 50 EG
Property damage: 20K
Reported by: AMATEUR RADIO

Thunderstorm Wind in WORCESTER, MASSACHUSETTS
From 20-AUG-04 19:45:00 to 20-AUG-04 19:45:00 (EST)
Location: WINCHENDON
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Thunderstorm Wind in FRANKLIN, MASSACHUSETTS
From 20-AUG-04 15:40:00 to 20-AUG-04 15:40:00 (EST)
Location: SUNDERLAND
Magnitude: 50 EG
Property damage: 10K
Reported by: AMATEUR RADIO

Thunderstorm Wind in MIDDLESEX, MASSACHUSETTS
From 20-AUG-04 16:00:00 to 20-AUG-04 16:00:00 (EST)
Location: NORTH READING
Magnitude: 50 EG
Property damage: 15K
Reported by: AMATEUR RADIO