Although tornadoes are more frequent in certain other parts of North America, they are not as rare around Newfoundland as we might first think. In the evening of August 16 past, a tornado touched down at Bishop's Falls and Botwood in central Newfoundland. On September 6, 1996, a tornado passed through Trinity, Trinity Bay. Less recent and lesser known tornadoes have occurred on the Burin Peninsula (1987) and along the Gander River (1983). Other tornadoes have undoubtedly touched down in uninhabited areas and have gone unnoticed.
A tornado is a small but very intense vortex of rapidly spinning air. Moisture, dust and debris collected by this spinning column of air make a tornado visible to you and me - otherwise it would be as invisible as the air we breath. These very high winds, which can reach 500 km/h and have been known to lift a vehicle off the ground, give the tornado its destructive force.
A tornado only occurs within a violent thunderstorm. Since the meteorological conditions necessary to produce these types of thunderstorms do not often occur in Newfoundland, tornadoes are, indeed, rare in this part of the world.
Tornadoes range in size, wind strength and lifetime. Some very small tornadoes may carry wind speeds in excess of 200 mph and may last for more than an hour. Others may touch down for only a few minutes. The Fujita scale, which ranges from F0 to F5 in increasing intensity, is widely use to categorize tornado strength. The Bishop's Falls - Botwood tornado of August 16 tornado was probably a F0 or F1. F3 to F5 tornadoes are more commonly seen in Tornado Alley in the United States.
Within Canada, tornadoes occur most frequently in the Prairies and in southern Ontario. The most devastating Canadian tornado killed 28 people in Regina in 1912. The Edmonton tornado on July 31, 1987 killed 27 people.
Tornadoes should not be confused with dustdevils, which are small whirlpools of air that have the general shape of a tornado but are much weaker and usually occur on a hot sunny summer's day. Another associated phenomenon is the waterspout, which occurs over water and has also been observed in Newfoundland coastal waters. Funnel clouds refer to a tornado that is not in direct contact with the ground.
The August 16 tornado touched down near Main Street in Bishop's Falls at around 8:07 PM, covering a path of about 500 feet before lifting back into the thunderstorm. Trees and fence posts were uprooted and debris was tossed freely around. The incident lasted less than a minute but left a lasting impression on those who witnessed the event.
A few minutes later, another tornado passed through nearby Botwood. As in Bishop's Falls, the tornado descended from the thunderstorm and remained in contact with the ground for several seconds. Before receding into the thunderstorm it caused considerable damage to trees, windows and some free-standing structures. One gentleman watched his vehicle rocking so heavily that he felt it would flip over if the tornado had not moved off.
Fortunately, no one was injured in either Bishop's Falls or Botwood. Tornado experts advise that you should protect your children and yourself from the tornado and flying debris. Seek shelter quickly, stay away from windows and doors and above all, resist the temptation to watch a tornado. Your first tornado sighting should also be your last.
Copyright, Sept. 14, 1998.
Bruce Whiffen.