Thursday, January 1, 2009

First radar hook echo ever recorded !

Scientists from the Illinois State Water Survey recorded in April 53 the first hook echo with a war radar (photo above is taken from their web site). The movie is here and is impressive (youtube).

The presence of a hook echo on a radar image in US is enough to issue a tornado warning. If you don't, you get in trouble. The warnings get to the Police. If the Police officer doesn't push the sirene button once he got the warning, he gets in big trouble.

The hook echo is a consequence of rotation in the storm (the mesocyclone), is a wrapped column of air in strong rotation, and the storms that have a mesocyclone can be very dangerous, with hail, flashfloods and strong winds; only 60% of the supercells are tornadic.
The first conference in Europe where have been presented cases with Tornado in Europe was Eurotornado, in February 2000, in France, Toulouse, but tornadoes have been reported and studied long ago and actually before they have been studied in US !

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