A supercell thunderstorm built on June 1, 2011, over western Massachusetts and resulted in an EF3 tornado. As you can see from the above NASA satellite image above, the twister sliced a 63 km (39 mile) path of devastation across south central and southwest parts of the state. The tornado widened to about 0.8 km (0.5 miles) in the Brimfield State Forest.
According to the National Weather service, as the tornado touched down initially in Westfield in Munger Hill section, its damage was limited to just the trees of the region. But as it traveled to West Springfield, it quickly intensified.
Below is a video of the tornado as it tracked from West Springfield across North End Bridge and Memorial Bridge into downtown Springfield. Water can clearly be seen being sucked up into the twister as it tracked along the river.
Below is an animation created from NASA satellite images showing the development of the line of thunderstorm cells that created the massive tornado that hit Joplin, Missouri – the deadliest tornado for 60 years. The Joplin tornado can be seen at the center of the video.
Below is another NASA animation showing 5 days of intense storm activity that created tornadoes across the Midwest U.S., including the Joplin tornado on May 22. The video also shows the progression of the May 24 storms moving from Arkansas, Illinois and Missouri into Mississippi, Ohio, Kentucky, Tennessee and Indiana.