EF1 tornado, Indian Orchard to Brimfield, Massachusetts, June 1, 2011

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mphthis tornado

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF1

Date

June 1, 2011

Touchdown

6:32 PM EDT (22:32 UTC)

Lifted

6:40 PM EDT (22:40 UTC)

On the ground

8 minutes

Path length

4.2 miles (6.7 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

0

County

Hampden County

Touchdown point

42.140, -72.480

Lift-off point

42.150, -72.400

Record number

1106011632-01

An upper level closed low over southern Ontario tracked across Quebec while at the surface, a cold front over western New York crossed southern New England in the evening of June 1. An environment characterized by high CAPE (2000-3000 J/kg) and high shear (greater than 200 m2/s2) was in place across western Massachusetts. In addition, mid level lapse rates were an impressive 7 to 8 C/km. Thunderstorms forming ahead of the front organized into discrete supercells in an environment highly favorable for tornado formation. ||While convection fired early in the day along a weak low level theta-e ridge across north central Massachusetts and southern New Hampshire, clearing allowed for rapid destabilization in the afternoon. ||Thunderstorms developed during the morning ahead of the cold front from eastern Pennsylvania into southeast New York and Vermont. By about 3 pm, the storms entered western Massachusetts and were in the form of discrete supercells. By 4 pm, several supercells had developed across southern Vermont, southwest New Hampshire, and western Massachusetts. At that time, the supercell which eventually produced the most significant tornado entered Hampden County from the Berkshires. This cell produced what was evaluated to be an EF-3 tornado touching down in Westfield and continuing on a 38 mile long trek through West Springfield, Springfield, Wilbraham, Monson, Brimfield, and Sturbridge. This tornado was on the ground for an estimated 70 minutes.||About two hours later, another supercell tracked just to the north of the storm track of the EF3 tornado. While its rotation was not as strong, it produced brief tornadoes in Wilbraham (EF1), North Brimfield (EF1), and Sturbridge (EF0).||While the focus was certainly on the tornadoes and their damage, damaging winds, large hail up to two inches in diameter, and some flash flooding also occurred across southern New England.

The tornado touched down in the northwest corner of Wilbraham and continued east crossing Main Street and Mountain Road, but remained south of Route 20. Most of the damage was to trees with large limbs snapped off, as well as numerous trees downed. Several trees were uprooted.||All associated property damage estimates are included in the EF3 tornado that occurred in Hampden and Worcester Counties.

The tornado touched down north of Brimfield, west of Route 19. It then crossed Route 19 and lifted near Tower Hill Road. The damage was surveyed on the ground and by aircraft and consisted of trees with large limbs snapped off, as well as numerous trees downed, a few of which were uprooted. This tornado was produced by the same thunderstorm that produced the North Wilbraham tornado.||All associated property damage estimates are included in the EF3 tornado that occurred in Hampden and Worcester Counties.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

25 minutes of warning. NWS BOX issued a tornado warning for this county at 22:07 UTC, 25 minutes before the tornado touched down, in force until 23:00 UTC.

The county was under a tornado watch, issued at 17:00 UTC and running to 23:43 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:45 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Chicopee/Westover (CEF), 10 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Boston radar (KBOX), 110 km away, was scanning. The volume nearest the touchdown began at 22:32 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2011 tornado in MassachusettsEvery tornado in Massachusetts since 1950Warnings in force in Massachusetts nowThe forecast where you are

11 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.