The legendary “tornado alley” doesn’t run through Massachusetts.
But for one day this week, it took a detour.
Normally found prowling the plains states or swirling through the southern states, tornadoes - a trio of them - hammered Western Massachusetts Wednesday, killing three and destroying or damaging hundreds of homes and businesses in Hampden and Worcester counties along a nearly 50-mile corridor from Westfield to Charlton.
However, as rare as serious tornadoes are in this region, they are not unprecedented.
In fact, in deaths wrought by tornadoes by area, Massachusetts ranks first in the nation. The frequency of tornadoes - three to four a year on average - is lower than many other states, but because of this state’s large population density and relatively small land area, the deaths per square mile are higher.
As evidence of this, the tornado of June 9, 1953, became one of the deadliest in the nation’s history - and the deadliest ever in New England - when it barreled through the city of Worcester, ultimately killing 94 people and leaving 10,000 homeless.
Wednesday’s events were still more evidence for this.
“I think everyone is surprised by the intensity of these tornadoes,” said Michael Rawlins, a climatologist at the University of Massachusetts Climate Research Center.
“What is unusual and rare about this event is the intensity ... combined with the location in which they occurred. Tornadoes in this region are typically short-lived. The fact that several tornadoes struck a highly developed area led to the large amount of damage,” he said.
The heart of tornado territory in the United States, the so-called tornado alley, extends from Texas up to the Dakotas. There, warm air off the Gulf has a chance to confront cold air from Canada amidst the strong winds on the plains, creating the volatile thunderstorms that can spawn tornadoes.
In New England, the same conditions don’t exist, but if the region does have a tornado alley, it is from northwest Connecticut through the Pioneer Valley to Worcester, said Eleanor Vallier-Talbot, a meteorologist with the National Weather Service’s Taunton forecasting office.
“Basically, it’s the way the winds set up. It’s usually a southwest wind with warm air that stays over the area” and sets up a confrontation with colder Canadian air, she said.
“Farther east, the wind comes off the water. It’s just cool enough that thunderstorms will tend to lose power,” she said.
There have been nearly three dozen tornadoes that have touched down in the Pioneer Valley since 1950, according to tornadopaths.org, a website based at University of Michigan that compiles tornado data.
Most of those were F0 and F1 tornadoes, the weakest on the Fujita scale that runs from 0 to 5, and their paths were usually less than a quarter mile in length.
Until Wednesday, the strongest tornado to strike the valley was an F3 that touched down briefly in September 1971 on Landy Street in the Florence section of Northampton. However, its path was shorter than a football field.
Within Massachusetts, there have been 152 tornadoes recorded since 1950, including three F4s and five F3s, according to another online site, the Tornado History Project.
The 1953 Worcester tornado - rated an F4, perhaps reaching F5 at times - began in Petersham. It set down just before dinner time and close enough to Quabbin Reservoir that boaters saw it form from the water.
For the next hour and a half, the tornado plodded east, reaching Worcester about 5 p.m., just as many businesses were letting out.
In that city alone, 66 people died. It was later determined that there were about 8,000 people in the area of Worcester where the tornado hit, and of those, 800 were either killed or injured enough to be taken to the hospital.
The tornado finally dissipated near Southborough about 5:40 p.m. In places, its path of destruction was a mile wide.
The debris field was phenomenally large. An item from the twister that originated in Holden was found 110 miles away on Cape Cod.
Chunks of a mattress were lifted high enough into the tornado that they were coated with ice and dropped in their frozen state into Boston Harbor.
The Worcester tornado was the costliest in U.S. history to that point, doing an estimated $53 million in damage (nearly $425 million in today’s dollars). Some 10,000 people were left homeless and 4,000 buildings were damaged.
Proving to be more costly was the F4 tornado of Oct. 3, 1979, that touched down in Windsor, Conn., and cut an 11-mile path of destruction to Suffield, near the Massachusetts line. It killed three people and injured nearly 500 others.
The tornado swept through the heart of tobacco growing country, destroying numerous curing barns.
It also came close to Bradley International Airport in Windsor Locks just as a United Airlines plane was about to land. Seeing it, the pilot quickly aborted the landing.
However, the tornado did strike the New England Air Museum nearby, destroying about two dozen vintage planes.
When it was done, the tornado would go into the record books as one of the 10 most costly in U.S. history, causing an estimated $200 million in damage (nearly $600 million in today’s dollars).
Among the other powerful tornadoes that have struck the state was one that moved into the Berkshires from New York state on May 29, 1995.
An F3 tornado, it moved fast, covering seven miles in just 10 minutes. In Great Barrington, it destroyed much of the town’s fairgrounds.
Three people were killed, two students and a staff member from a private school in Great Barrington, the Eagleton School, when their car was picked up and thrown by the tornado.
Some 27 people were injured, more than 100 homes and businesses were damaged or destroyed, and thousands of trees were toppled by the twister. Its winds were exceptionally strong, estimated to range from 158 to 260 mph.
It will take weeks, perhaps months, to assess the damage done by Wednesday’s tornadoes, but already, they have found a place in the history books. They were also a reminder that tornadoes are not purely history in this region.
“I never thought I’d see one like this up here in New England,” said Vallier-Talbot.