Hurricane, cyclones? What's the difference? Nothing much really, it's simply that people in different areas traditionally use different names for the same thing. However tornadoes are different. They are smaller, of a more local nature with a shorter life and are a part of a large storm system, while hurricanes and cyclones affect very much larger areas, refer to an entire storm system, and can be tracked for several days. Hurricanes come from the Atlantic ocean and cyclones occur in the Pacific Ocean.
Tornadoes strength is measured on the Fujita Scale, named after Tetsuya Theododore Fujita:-
|F0||Gale||40 - 72 mph||Some damage to chimneys, broken branches on trees, shallow rooted trees pushed over,hoardings damaged.|
|F1||Moderate Tornado||73 - 112 mph||The lower speed is the beginning of hurricane winds speeds, roofing slates removed, mobile homes and caravans blown over, moving cars pushed off the road, garages damaged.|
|F2||Significant Tornado||113 - 157 mph||Considerable damage to property, Entire roofs torn off houses, mobile homes etc. destroyed, railway carriages pushed over, large trees snapped in two and uprooted, light objects act as missiles.|
|F3||Severe Tornado||158 - 206 mph||Roofs and walls torn off, trains overturned, most trees in forests uprooted.|
|F4||Devastating Tornado||207 - 260 mph||Well-built houses flattened, houses with weak foundations relocated, cars thrown around, large objects act as missiles.|
|F5||Incredible Tornado||261 - 318 mph||Strong houses relocated considerable distances, tending to
disintegrate, cars sized missiles encountered, flying around 100 m, bark
stripped from trees,steel-reinforced concrete structures badly damaged.
In the movie Twister they called this "The Finger of God".
|F6||Inconceivable Tornado||319 - 379 mph||Very unlikely and hard to identify amongst the carnage from the F4 and F5 winds on the outside of such a storm. The ground itself may have swirl patterns.|
BBC Feature - Hurricanes is just one of many articles from the BBC's site Weather Feature section. Like all BBC articles, it is well written, and not difficult to understand.
Discovery Online Hyper Hurricanes at has many excellent videos and lots of subsections to visit. The Discovery Chanel articles, like the BBC ones, are usually interesting reads.
All About Hurricanes is all about hurricanes, surprisingly. Bet you weren't expecting that, were you?
How Stuff Works - Hurricanes is a featured set of pages from a site that explains how things work. The pages are good, and the site is a popular choice or explanations of many things, an online encyclopedia that is continually being added to. you can try asking the experts a question and it might get featured as their question of the day.
Tornado Severe Weather is an informative page on tornadoes, at The Disaster Centre, whose home page covers all sorts of disasters! Including hurricanes, car accidents, terrorists threats, US cause of death statistics, droughts, earthquakes and a whole lot more. Trouble is, the home page is very big and takes a little bit longer than most to fully load.
TORRO, the UK Tornado and Storm Research Organisation has a lot of stuff of interest to UK pilots.
The Tornado Project Online! is a very well organised site for tornado fans. It has many sections and sells some beautiful tornado posters, videos and even T-shirts with tornado designs. In it's first two years it received over 750,000 hits (by browsers, not tornadoes). Can't be bad!
Unravelling the mysteries of twisters - an MSNBC feature on twisters, it includes some video shots and a a straightforward discussion of twisters, american for tornados.