It started with a severe thunder and lightning storm.

Elsie Whidden, a high school English teacher, was in her West Gardiner summer home on Lake Cobbossee when she looked across the lake and saw the water begin to rise and pick up speed. Suddenly, she heard what sounded like a racing train.

The lake water had risen higher than 6 feet, moving up the shore line.

“I knew it wasn’t a thunder and lightning storm — I knew it was something much different,” Whidden said recently. Other observers later said they saw a funnel cloud, which had originated over land, moving across the lake.

She raced to her basement as the windows in her living room shattered around her. When she emerged five minutes later, her house looked as if a bomb had hit it.

Everything was covered in trees. Her front deck was demolished, as was the Peugeot station wagon parked in her driveway. Her boat, docked on the lake, had been tossed onto a field 200 feet away.

Whidden’s house had been struck by a tornado that had touched down off Route 135 in Monmouth and swept over Lake Cobbossee. The July 1996 tornado brought hail and rain to parts of western Maine, but no one was injured.

Whidden never saw the funnel cloud coming toward her, but the experience left her in shock for a month. She still is making repairs to her home.

“I had heard there were some tornadoes in the northern part of Maine — but I had no idea,” she said.

Just last week, an F-1 tornado touched down in Newry in Androscoggin County, knocking down several hundred trees in a woodlot, according to John Jensenius, warning coordinator meteorologist at the National Weather Service in Gray.

In Maine, tornadoes generally are seen as a phenomenon that doesn’t occur in New England, Jensenius said.

Residents might be surprised to find that at least two tornadoes occur every year in Maine. The tornado that struck Whidden’s house was not a freak occurrence.

“There’s a lot of people who don’t realize that tornadoes happen,” Jensensius said. “We certainly don’t have the violence that occurs in the Midwest.”

It’s true that the number of tornadoes in Maine and other states in New England pales in comparison to states such as Texas, which gets about 125 tornadoes a year.

Researchers, however, have dubbed a small area of New Enlgand “Tornado Alley.” This area, which encompasses parts of New Hampshire, central Massachusets and central Connecticut, is a region in which tornadoes move from southwest to northeast, the typical direction of their movement.

Most tornadoes in Maine occur in the western half of the state, closer to New Hampshire, because the farther west and south one goes in the United States, the more tornado activity there is, said Hendricus Lulofs, warning coordinator meteorologist at the NWS in Caribou.

It is in these regions that the ingredients for a tornado can be found — tropical air mass and winds that change with height, Lulofs said.

Tornadoes are characterized by their funnel-shaped formation and wind speeds of up to 350 mph. Hurricanes are generally larger than tornadoes, but their wind speeds are much slower, starting at 74 mph.

Tornadoes should not be confused with microbursts, severe downdrafts during thunderstorms that look similiar to tornadoes and often do tornadolike damage. Since 1950, more than 83 tornadoes have been reported in Maine. At least 14 have occurred in Aroostook County. Kennebec, Penobscot and York counties have been struck by a total of approximately nine tornadoes.

Maine’s only tornado-related death occurred, according to a published report, on Aug. 11, 1954, in Caribou when a woman died after being thrown from her house during an F-2 tornado.

According to Jensenius, another recent tornado occurred in Sweden, Oxford County, on Aug. 13, 1999.

The late-night tornado created a damage path a mile long. Hundreds of trees were uprooted, and a home and utility shed were damaged. No one was injured.

This level of destruction is typical for tornadoes in Maine that normally fall under the F-0, F-1 or F-2 categories on the Fujita scale, a tool used by meteorologists to determine the rate of intensity of a tornado. Lulofs said that in the last five years, there have been no tornado-related deaths in Maine.

The Fujita scale, established in 1971 and named after the late Tetsuya Theodore Fujita, a meteorologist from the University of Chicago, measures the level of damage after a tornado has passed over an area. Scientists then can determine wind speeds of the tornado.

The scale ranges from F-0 to F-6, with F-0 describing a gale tornado with winds speeds of 40 to 72 mph. Damage during gale tornadoes is usually limited to chimney wreckage and broken tree branches.

A tornado measuring F-6, otherwise called an inconceivable tornado, hardly ever occurs and is characterized by wind speeds of 319 to 379 mph.

Both the 1999 tornado in Sweden and the tornado that struck Whidden’s house measured F-2 on the Fujita scale.

With wind speeds of this intensity, it’s well that the national average warning time for tornadoes has increased four times in the last 10 years. Using radar, meteorologists can detect a tornado and issue a warning up to 14 minutes before it strikes. This is a far cry from the two-minute average warning time of 10 years ago.

Still, many Mainers are unaware of warnings or don’t think to turn on a radio during a severe storm. The NWS in Maine is working to change this, Lulofs said.

This past spring, the NWS held a weather awareness week, informing the public about severe weather systems and how to handle them.

The NWS plans to hold a similiar weather awareness week annually at the end of April or the beginning of May.

For more information on how to handle severe storms, the NWS Web site is at http://www.srh.noaa.gov/oun/severewx/safety.html.