Tornado Alley (PROG)

[F6]

fuagf -- those 6 at once are landspouts, inherently weaker circulations structurally/thermodynamically distinct from supercell tornadoes (as in both yesterday's twins in Nebraska and the 1965 twins in Indiana) -- landspouts like those not infrequently occur in small bunches in certain meso/micro environments such as the one in your video -- and are close kin to e.g. the Great Lakes lake waterspouts that quite often accompany stronger bands of lake effect snow squalls as those come toward shore during those events; it is not at all uncommon for a number to be visible at once, e.g. (all south shore of Lake Erie):


http://www.conneautohio.us/graphics/lake_erie_waterspouts3.jpg , via http://www.conneautohio.us/


http://www.conneautohio.us/graphics/lake_erie_waterspouts2.jpg , via http://www.conneautohio.us/


http://fishandboat.com/water/lakes/erie/spouts/waterspouts.htm

speaking in terms of true supercell tornadoes that are each clearly distinct, separate rotating updrafts up to at least some altitude up above the cloud base/up into the parent supercell, as with both yesterday's Nebraska twins and the 1965 twins in Indiana (which is to say, leaving aside the multiple subvortices that together comprise the detail of the structure of a single larger multi-vortex supercell tornado/rotating updraft), no, I have never seen or heard of three such true supercell tornadoes/distinct rotating updrafts grouped that closely together -- perhaps there's been such an event where a third, or even a couple more, were onging simultaneously within a larger radius of a few up to 10 or 20 miles, but not in that close a proximity to the first two; occasionally there'll be a bunch of relatively small but rapidly rotating storms that'll get cranked up all at once in a relatively small area and pepper the area with a bunch of tornadoes in a short period of time (we had such an event near here two years ago [{linked in} http://investorshub.advfn.com/boards/read_msg.aspx?message_id=74010602 {and preceding} and following], no twin tornadoes but maybe a dozen tornadoes in a 6-county area, a couple strong, from a batch of storms that just went/spun up under very locally very ripe conditions over just a couple of hours)

to have 'em here -- from yesterday in Nebraska:

June 16, 2014. Pilger, Nebraska. "The Twins"

Published on Jun 17, 2014 by drewsroo [ http://www.youtube.com/channel/UCjJo5SOC5sYxee1BniqJuNg ]
Tornado #1 is the tornado that unfortunately hit Pilger causing extreme damage and loss of life. A new circulation formed south of this monster and soon 2 violent tornadoes were simultaneously on the ground. We drove to within less than 1/4 mile of the "twins" as they merged and crossed the road in front of us and became wrapped in rain. We blasted east and yet another violent tornado emerged complete with a satellite rotating around it. We then came across some major damage to a farm. Thankfully the house was spared but the outbuildings and pig barn were not so fortunate...
http://www.youtube.com/watch?v=1P1tRUBGzBA [with comment]

Chaser: Twin tornadoes extremely violent

Published on Jun 16, 2014 by CNN [ http://www.youtube.com/channel/UCupvZG-5ko_eiXAupbDfxWw ]
Storm chaser Reed Timmer describes the double tornado that touched down in Nebraska.
http://www.youtube.com/watch?v=_e6EesLbg04 [with comments]

June 16th, 2014: Twin Large Tornadoes near Wisner, Nebraska!

Published on Jun 16, 2014 by DrTornadoCooley [ http://www.youtube.com/channel/UCaVXhofmhU1DgB4V0g7d5Uw ]
Video of a stovepipe and multi-vortex large tornado simultaneously on the ground NE of Wisner, Nebraska on June 16th, 2014.
http://www.youtube.com/watch?v=D4_tpkTa808 [with comments]

Violent tornadoes in Nebraska - June 16, 2014

Published on Jun 16, 2014 by StormTimelapse [ http://www.youtube.com/channel/UCMAyY8iFZAPsisEeQhX_8gA ]
Storm chaser Chad Cowan documented around 5 strong tornadoes in northeast Nebraska on June 16, 2014, including one that did significant damage in Pilger.
http://www.youtube.com/watch?v=rWmwL2ryftI [with comments]