Tuesday, May 21, 2013

COTW: Tornado Alley

The Southern Plains are infamous for developing killer tornados, as this chart shows:


The EF-5 tornado [red, above] that obliterated wide swaths of Moore, Oklahoma yesterday developed very rapidly so residents were caught outside and in school buildings.  An EF-5 contains winds in excess of 200mph.  The violent twister was in the same big league and followed nearly the same path as the 1999 tornado in Moore that killed 41. The 1999 tornado exhibited the strongest winds ever recorded on Earth, clocked at 318mph, and ranks as the fourth highest on record for most damage. The latest "storm of storms" stayed in contact with the ground for forty minutes and clawed a one mile-wide path of destruction at its peak.  A classic combination of wind shear and moist air from the Gulf colliding with dry air from the Rockies spawned the supercell thunderstorm and associated vortexes.

A survivor's tale: