Australian Severe Weather Forum

Mike,

Can you lead me to your source of information regarding suction vortices and satellite tornado differences.

I would say this has a suction vortice:

http://iatse354.com/354/Chases/Gburg/images/0020.jpg

Regards,

Jimmy Deguara

Too many sources to remember ! - I've just read a whole lot on them through websites and from other articles found online and browsed.  This video of Dr Greg Forbe's explanation during a large tornado which showed three suction vortices is here:

http://www.weather.com/multimedia/videoplayer.html?clip=2635&collection=topstory&from=vid_brws2&tab=3&nav=84

I also read a while back on Fujita's theory on suction vortices (Fujita T, 1981, Tornadoes and downbursts in the context of generalized planetary scales, Journal of the Atmospheric Sciences, 38[8], pages 1511-1534.) and also his theory after he got hold of that amazing 35mm tornado film from the Xenia event.

 I understand that satellite tornadoes form next to the original funnel and then dissappear only to reappear on the other side (circulating per se) and that suction vortices are as a result of the separate wind flow vortices turning anticlockwise and clockwise next to each other within the thunderstorm and that the separate vortices usually are seen in the storm's dissipating stage, but initially the funnel can actually contain more than one vortex but co-joins to create the main funnel when at the mature stage and what we see once grounded.

I remember seeing a wonderful computer animation of wind profiles within a supercell and you think I can find it again?  No!  I'll hunt it down and post the link.  It's the best i've seen and the amount of wind direction, vorticity and inflow/outflow profiles blew me away. Air is not just sucked in and blown out - it's litterally blown apart and dispersed to all regions of the storm!

Just found one of my printed resources - it can be found at http://docs.lib.noaa.gov/rescue/mwr/098/mwr-098-01-0029.pdf  It's 45 pages long in PDF form but it is Fujita's assessment on the 1965 Palm Sunday tornado outbreak. He gives explanations and theory on suction vortices and the like.... It's Fujita - what more can one say.


Mike

Mike,


Do you think it is as general as this?

My main issue is that you corrected Anrej in saying that all were suction vorticies or am I mistaken? I would have thought that a funnel reaching the ground would be classed as a tornado and that being it circulated around the major vortex is a satellite tornado. However, I have not sourced definitions myself. So I could be wrong.

Regards,

Jimmy Deguara

No, i wasn't correcting him, just making an observation of his question.  I'm not saying that all were suction vortices, but I was working out what the 'buldge' was that Andrej talked about.

 If it is a suction vortice did it dissipate or did it form with the main funnel ? Hard to tell by one or two photographs and without video to see where it went.  I'm not too sure of the sizes that satellite funnels get but that they do spin around the circumference of the main funnel grounded and in opposite direction to it also.

 So yes, I agree re satellite funnels/suction vortices are classed as tornadoes.

If the suction winds are present right around the main ground zero funnel and also present within the area of this region then yes you would have either one visible.  I would hope that it's not as general as this because there are so many dynamics (kinematic?) causing other things to happen around this area of interest.

There has been some discussion as to whether these things are actually tornadoes - but as a direct result of wind vorticity and of the storm itself they surely must be classed as tornadoes - even if they don't touch the ground.  I don't believe that you have to see it grounded to class it a tornado - the storm is producing something only when certain criterian are met right? 

From the photos it looks like on the LHS it could be a parent vortex but did not form and on the other side a satellite - but who knows - without the footage none of us can judge it's movement during the tornado phase!  Does that help?

Mike