Right now, tornado (and severe thunderstorm) warnings are issued when one of two things happens:

1) A tornado or a funnel cloud is spotted
2) Doppler radar indicates strong rotation and the forecaster believes a tornado is possible or likely

It's always better to detect the tornado vortex signature on radar before a tornado actually develops. There is some lead time, should a tornado actually develop, and people have time to take cover. But the bottom line is that we still warn based on observations, not on a forecast.

A fundamental reason for conducting VORTEX2 is to investigate tornado formation to understand why some supercell thunderstorms are tornadic while others are not. One reason that has been suggested is that warmer rear flank downdrafts are more favorable than colder rear flank downdrafts for tornadogenesis. Physical reasons for this have been proposed, but at this time it still remains untested.

It is hoped that by investigating the storm environment, there will be a better understanding of why some supercell thunderstorms are tornadic while others are not. If the properties of the rear flank downdraft influence the tornado potential, those observations of wind speed, temperature, moisture, and pressure are important. The purpose of understanding why some supercells are tornadic while others are not isn't just for meteorologists to publish papers in journals and get NSF funding. The purpose is to better understand tornado formation in hopes that in the future, tornado warnings are based on forecast tornado potential instead of observing the rotation. If forecasters can predict when tornadic rotation will develop in storms, it will increase the lead time on warnings. It will give people valuable time to alert others of approaching dangerous weather and to take cover.

As another comment has pointed out, the TIV is exactly such a vehicle. The purpose of the vehicle is to attempt to get good observations of near-surface winds in a tornadic vortex. Mobile radars have done a good job of measuring winds at heights of 75 or 100 meters above the surface. But the question is how strong are the winds near the surface where they actually have the potential to do damage.

In addition to the TIV and the DOW (Doppler On Wheels), pods with instruments are also deployed to take observations.

I'm not aware that the TIV will be involved in VORTEX2. However, there will be plenty of mobile radars, including Josh Wurman's DOWs. The pods will also be deployed.

Texas Tech has developed instruments that are referred to as the sticknet, also for taking observations. These are designed to withstand strong winds and remain fastened into the ground.

Another new technology that will be used during some events in VORTEX2 is unmanned aircraft systems. VORTEX2 is one opportunity to demonstrate the usefulness of unmanned aircraft systems in taking observations. And one goal is to get an unmanned aircraft into the rear flank downdraft of a supercell. That's not in the tornado, but it's pretty close.

One correction about #3... The circulation must be present both at the base of the cloud and at the surface. In other words, if it doesn't touch down, it's just a funnel cloud. In order to be a tornado, it must actually touch down. And regarding #2... The population in the Great Plains tends to be relatively sparse compared to other regions of the country. So, people do tend to live in areas where tornadoes are less frequent.

The primary domain of VORTEX2 includes much of several states, and the 900 square miles is clearly a typo. Also, VORTEX2 isn't limited to that domain. If there's tornadic thunderstorms outside of the domain and no good setups within the domain, VORTEX2 could deploy outside of the domain. The primary considerations were the road networks and the lack of trees making observations easier. Areas such as the sandhills of Nebraska are outside of the domain and the road network is limited, but if that's the only thing to chase on the Plains, VORTEX could deploy there. The preferred domain is in western Oklahoma because of the observations available (CASA radars, the OK Mesonet, etc...). But VORTEX2 isn't limited to that region.

The purpose of VORTEX2, as some comments have questioned, is to test some theories about the evolution of tornadoes in thunderstorms and why some supercells produce tornadoes while others do not. In a very simplistic explanation of what's going on, vorticity about a horizontal axis is tilted to where vortex lines intersect the ground, thus tilting the rotation into the vertical and transferring the rotation to the surface. Part of the tilting is done by the rear flank downdraft, and part of the tilting is done by the updraft. However, if the rear flank downdraft is too cold, the updraft cannot lift the air in the downdraft too much, and the rotation isn't tilted into the vertical. Present theories suggest that warmer rear flank downdrafts favor tornadogenesis. Here's a link to a presentation by Dr. Markowski of Penn State about the current theory regarding tornadogenesis. VORTEX2 is an attempt to gather high resolution data sets for many supercells to test the current theory. Obviously there's much more to VORTEX2, including the testing of unmanned aircraft in storm environments. But one major objective is to test the current theory regarding tornadogenesis.

Just a few months ago, I upgraded to the AT&T version of the Palm Centro. I was a little disappointed to learn that the AT&T version of the Centro doesn't support 3g while the Sprint version does. If AT&T was going to upgrade to 3g at the expense of 2g, they should have made as many 3g offerings available as possible. I've noticed as well that my signal strength has seemed poorer in many areas of Missouri lately than it was when I first purchased my Centro, but I'd never associated it with anything AT&T had done.