Oklahoma, Central USA has been hit by what is being reported as the most severe tornado in living history. The category 5 event arrived in the suburb of Moore at 3pm on Monday afternoon 21st May and ripped through homes, a primary school and hospital for around 40 minutes. The picture below shows the preliminary map of its track. The death toll 12 hours after the disaster was reported as 52 although figure has now been lowered to 24, credit to rapid response for the local authorities and community. For the latest information click here for the US Weather Channel. The BBC also has some good coverage, two short and very useful video clips can be found here.
What is a Tornado?
Tornadoes are local scale natural disasters, a vortex is created with winds reaching and exceeding 200mph. They come about due to unseasonably hot weather where an area of land is warmed intensely causing air to rise rapidly. As it does so colder air is sucked in and warmed causing the vortex to spin at greater speeds. The whole system then begins to accelerate and move. Eventually the vortex becomes unstable and collapses. Tornadoes are measured using the enhanced Fujita scale which has 5 scales based upon wind speed and the amount of damage it creates. To learn more click here. The UK actually receives more tornadoes than anywhere else in the world, however their intensity is weaker than in the USA because the extremes in temperature are much lower. The area where this most recent event has struck is known as tornado alley due to the high level of frequency of tornadoes in the area.