Ed DunhamAdministrator
(Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017))
Sun Jul 06 2008 12:23 AM
Re: Question about Storm Formation - July 3rd, 2008 incident

From your description it seems like you viewed the rotating base of a mesocyclone. Mesocyclones are thunderstorms, sometimes massive ones, where the entire thunderstorm (or most of it) achieves rotation. They are often precursors of funnel clouds/tornadoes that form within the mesocyclone itself and this rotating collar cloud can be very close to the ground. It projects downward, often dramatically, from the base of the thunderstorm.
Cheers,
ED


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