In Depth Analysis and More photos of the Mexican UFOs
Showing how the FLIR infrared camera works (that captured the original pictues), and looking at all the frames and in contrast, you can see how the supposition that this is ball lightening is not working.
Ball lightening is yet to gather in linear clumps (with halos around it), and move back and forth and then shoot off, especially without being seen by eyewitnesses (in this case, the pilots).
Interesting http://www.earthfiles.com/news/news.cfm?ID=711&category=Environment