Detailed text transcripts for TV channel - MSNBC - 20130522:07:10:00
Shear about a vertical axis. and then like an ice skater who brings her arms in and spins faster, you have all this moisture and energy being focused around this vertical axis. in a typical thunderstorm it usually snuffs itself out within about 30 to 45 minutes. but in these supercell thunderstorms they tilt over slightly due to wind shear, and that protects the warm updraft. and it sustains the warm updraft. so instead of dying out after 45 minutes it goes on hour after hour. and in the process...
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