A tornado is a localised and violently destructive windstorm occurring over land characterised by a funnel-shaped cloud extending toward the ground.
Most tornadoes form from thunderstorms. When warm, moist air masses and cool, dry air masses meet, they create instability in the atmosphere. Abundant low level moisture is necessary to contribute to the development of a thunderstorm, and a “trigger” (perhaps a cold front or other low level zone of converging winds) is needed to lift the moist air aloft. Once the air begins to rise and becomes saturated, it will continue rising to great heights to produce a thunderstorm cloud, if the atmosphere is unstable.
A change in wind direction and an increase in wind speed with increasing height creates an invisible, horizontal spinning effect in the lower atmosphere. Rising air within the updraft tilts the rotating air from horizontal to vertical. An area of rotation now extends through much of the storm. Tornadoes form within this area of strong rotation.
The phenomenon in Trinidad
In Trinidad and Tobago tornadoes such as those in The USA are almost unheard of.The funnel-shaped clouds seen locally have not been observed to extend from the base of the cloud to the ground. Strictly speaking our freak storms may not be tornadoes. However, our small twisters are increasing in number and frequency and are of concern to people.
There have been several tornado-like freak storms in Trinidad over the years, in places like Cunupia, Malick-Barataria, and Diego Martin. More recently they have occurred in Macoya (October 2006), Debe (August 05, 2007), Point Fortin (July 12, 2008 and July 03, 2012), Charlieville (August 09, 2009) and Carenage (December 02, 2011).
On most occasions the number of houses affected has ranged from one to twelve. The occurrence in Malick-Barataria several decades ago affected over 30 houses. In most cases the damage has been confined to roof damage and resulting water damage, but there have been instances of more substantial damage.
Are you covered?
The typical homeowner’s policy covers loss or damage to property by ‘hurricane, cyclone, tornado or windstorm including flood or overflow of the sea occasioned thereby’. The wording for hurricane on the commercial fire and special perils policy is similar to that of the homeowner’s policy.
The word ‘tornado’ in the policies mentioned above are not defined and should a claim arise one may have to look at the technical meaning of a tornado to determine if there is cover. The occurrences in Trinidad and Tobago have been described as small twisters, freak storms or unusually high winds. Unfortunately, the media (print and electronic) have often referred to them as ‘tornadoes’. Technically speaking they do not qualify as tornadoes.
The policies mentioned above also use the word ‘windstorm’. Again, it is not defined in these policies. A general definition of a windstorm is ‘ a storm consisting of violent winds’. The strength of a windstorm would not be that of a tropical storm. It is debateable whether mere high winds that affect just a handful of persons would qualify as a windstorm. It is also apparent that in many cases improper laying down of roofs or poor maintenance has been the real cause of the damage, especially when houses adjacent to those damaged suffer no damage. Insurance is not designed to pick up mere maintenance costs. It should also be noted that the perils of hurricane, cyclone, tornado or windstorm carry a deductible (same as an excess) of 2% of the sum insured, subject to a minimum amount (usually no less than $2,000).
In conclusion, it is safe to say that the policies would certainly cover the effects of a genuine tornado or windstorm. It is quite likely that some of the occurrences (wrongly labelled as tornadoes) may not be covered.