Storm Australian Severe Weather Forum
Severe Weather Discussion => General Weather - all topics not current severe weather. => Topic started by: Mike on 24 May 2007, 03:27:19 PM
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Do tornadoes actually have an 'eye' per se? I know they're not related but I've seen reports of survivors of the Greensburg event actually seeing the tornado's eye as it moved across them.
Also, do tornadoes of the EF4-5 wedge size (or any really) create a 'hollow' at the the top of the supercell because of its immense rotational force - does the meso actually 'pull down' on the storm at the area of producing the actual funnel and how far up into the storm tower does an actual meso go if from what i picture a meso to be as the rotating updraft core from where the funnel lowers from within this core.
To picture it i guess you could imagine holding a piece of material flat and then whilst pinching the centre underside and gradually rotating it and pulling it downward and hence creating a 'divet' at the top?
Would appreciate comments on this as it's just come to mind!
Mike
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Large violent tornadoes do have eyes relative to the strength of surrounding winds. Certainly one cannot assume to be safe there of course. This was certainly the case with the tornado at Greensburg with some region of relative calm depicted on radar.
Regards,
Jimmy Deguara
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Thanks and also how high inside these supercells does the meso go? Or in actual fact, how high inside the towers do mesos go? Has any data been done on this from probes that can give me an answer?
Mike
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This is off track a tad, but it relates to what i asked...
Following on from that...(this is not my way of thinking by the way, it's something I read and wanted to get a more informed opinion before replying to it)...
I viewed a post on a site and the person mentioned something about the weather up here... 'there has been too much low level shear to suppress initiation of convection and thereby giving us a "greenhouse" like effect'
There was no mention whether it was speed or directional shear, but myself looking at the sounding there was no directional shear until around 3-400mb. There was some speed shear below 500mb though - albeit he didn't mention which one.
From what I have learned to date is; that shear determines updraft/storm strength/type and to some extent the direction of storm motion and not whether it 'creates' the convection in the first place.
All the other indices must be looked at before that right?
If the CAPE and -LI levels were high then shear would play no part in whether there's convection because the atmosphere is unstable enough to create cloud formation (convection) anyway - there were no thunderstorms from the resultant sounding, but that would not be because of the shear - that's to do with everything else.
I'm pretty sure i'm right about that because that comment didn't sit well with me - but wanted to check!
Mike