What would be the perfect setup for a massive tornado outbreak

[STurner]

As far as numbers go what would be a perfect setup for a massvie tornado outbreak with over 100 tornadoes confirmed. Like for instance CAPE, wind shear, winds with height, LCL's, LLJ, SRH, low/mid level lapse rates, temperatures, and dewpoints etc. Something that would be the ultimate chase. Any ideas on what you would be looking for to get a perfect setup.

 

[Andrew Ryan]

There is NO perfect number that will scream tornado outbreak. We don't fully understand the ingredients for a tornado outbreak, hence the recent High Risk bust.

 

[Melissa Jablonski]

That's known only to God and he ain't tellin.
Melissa

 

[John Wetter]

Shane, a good idea would be to go back and look at case studies from big tornado outbreaks. There's tons of data out there available on Greensburg, Oklahoma City, Andover, Parkersburg... Etc. Etc. For the large numbers of tornadoes take a look at the big streak in May 2003.

 

[Mike Peregrine]

Jon Davies has a great page on his site with the parameters for supercells/tornadoes. I used to check it a lot to get an idea of what to look for, parameter-wise. There are tons of other things, though ... like synoptic and mesoscale features and observations that tell you how the atmosphere is actually behaving out there. The models and parameters give you a good starting point and a general idea, but you've got to pay attention to what's actually happening as a day progresses. It always seems to take me two or three chases to really fall into the groove with forecasting and obs for some reason. Every spring I feel a bit like I'm starting over with all of it.

 

[Darren Addy]

This is probably the page that Mike is referring to: http://members.cox.net/jondavies1/tornado_fcsting/sprcll_tors.htm

The table in the middle of the page gives you the parameters in a nutshell. For a look at more convective indices: http://www.crh.noaa.gov/lsx/science/indices.php
In the link above, ISOLD = isolated, FEW = few , SCT = scattered, NMRS = numerous.

You will find those numbers on the bottom of a SKEW-T (among other places) which is either a real or model sampling of the various layers of the atmosphere.

Note that you asked about an OUTBREAK, while the numbers above do not predict outbreaks themselves they are related. (Clearly if you have conditions favorable for supercells and significant tornadoes over a wide geographical area, then you have conditions favorable for an outbreak).