Double Tornadoes?

#1 04-02-2007, 05:15 PM

What unique weather conditions tend to cause double tornadoes, like two funnels or even two tornadoes on the ground?

#2 04-02-2007, 06:16 PM

Quote:

What unique weather conditions tend to cause double tornadoes, like two funnels or even two tornadoes on the ground?[/b]

2 thunderstorms* :P

davecarlsen · #3 04-02-2007, 06:35 PM

I've seen a few videos of what I'd call double tornadoes (2 definitely separate tornadoes within one mesocyclone--the tornadoes are about 3 to 5 miles apart) and I've even seen one in person, myself.

But often what gets reported as a double tornado is just a multi-vortex tornado.

Anyhow, in essence you'd need a particularly strong mesocyclone to do that.* So all the conditions that come together to form a mesocyclone are the preconditions.* They just need to be particularly strong.

Josh Richardson · #4 04-02-2007, 07:07 PM

Cant really say I would know why there could be a satellite TOR associated with another bigger one but there are different circumstances to everything.

dean · #5 04-02-2007, 08:33 PM

i think the rear flank downdraft can do this, it weakens one tornado and spawns another usually to the south (i think). or maybe a new updraft producing a tornado with an old updraft still producing at the same time?

davecarlsen · #6 04-02-2007, 08:44 PM

Okay, that makes sense, too, Dean.* I had forgotten about this: mesocyclone occlusion, where the inflow is being cut off from the old updraft by the RFD, and the new updraft is taking over.* This could also cause 2 tornadoes from the same storm at once.

I've also seen pictures of 4 or 5 waterspouts at a time.* Waterspouts are technically tornadoes, although most waterspouts don't occur with mesocyclones.* So a line of waterspouts could also be considered multiple tornadoes.

NWIASpotter · #7 04-02-2007, 09:32 PM

I assume you thought of this question after reading posts in StormTrack about the possibility of the two tornadoes on Wednesday be fairly close to each other and quite large.* Essentially, I think the only way you could get two good solid tornadoes would be to have two thunderstorms in line with each other.* As mentioned, the RFD situation could provide two tornadoes for a short time period, but doubtful that they would both be sustained.

Josh Richardson · #8 04-02-2007, 10:09 PM

Quote:

I assume you thought of this question after reading posts in StormTrack about the possibility of the two tornadoes on Wednesday be fairly close to each other and quite large.* Essentially, I think the only way you could get two good solid tornadoes would be to have two thunderstorms in line with each other.* As mentioned, the RFD situation could provide two tornadoes for a short time period, but doubtful that they would both be sustained.[/b]

Thats exactly why I figured he had to have meant that you have one large tornado and then another small one like a satellite tornado.* Otherwise, yeah if your referring to the large tornadoes near each other the other day I would say the same thing as Jayson.* A lot of those storms were very close in proximity and thus probably came from two different updrafts.

dean · #9 04-03-2007, 12:47 AM

here's a fine example: The 1965 Palm Sunday outbreak:

Dustin Wilcox · #10 04-03-2007, 06:34 PM

I saw two tornadoes on the ground side by side last Wednesday.* There was the large Wedge and then a decent sized stovepipe to the right of the Wedge, from what I could tell it didn't appear to be a "true" satellite tornado as I never noted it circling around the Wedge.* They were aprox. 300 yards apart and associated with the same Mesocyclone.*